Release Cosmopolitan v3.9.3

Avoid an --ftrace crash on Windows
Make more fixups and quality assurance
2026-11-08 08:08:04 -10:00 · 2024-10-08 19:58:32 -07:00 · 2024-10-07 18:39:25 -07:00 · 2024-10-07 15:29:53 -07:00 · 2024-10-02 04:55:06 -07:00 · 2024-09-30 05:54:34 -07:00
5321 changed files with 481620 additions and 320788 deletions
@@ -1,6 +1,10 @@
 # Run this command to always ignore formatting commits in git blame
 # git config blame.ignoreRevsFile .git-blame-ignore-revs

+# Upgraded clang-format to 19.0.0git
+89fc95fefd40413706ff1bdaac2e8d98b328dbf1
+# vim c++ filetype in modelines
+04c6bc478e082263d67c41bedbd033dde2d429eb
 # Ran clang-format
 f032b5570b4cd87c6bb4abb54c0b98e69c939955
 # Applied clang-format update to repo
@@ -21,3 +25,7 @@ c0eacf2eb1e1c0b3bd4f71f12fef258f5b249c3f
 da8baf2aa5ce93b958aca90a0ae69f537806324b
 # Run clang-format on most sources
 369f9740de4534c28d0e81ab2afc99decbb9a3e6
+# Get rid of .internal.h convention in LIBC_INTRIN
+86d884cce24d773e298a2714c1e3d91ecab9be45
+# Remove .internal from more header filenames
+31194165d2afca36c2315a6e7ca2f0797dde09e3
@@ -1,4 +1,10 @@
 # -*- conf -*-
 *.gz                         binary
-/build/bootstrap/*.com       binary
+*.so                         binary
+*.dll                        binary
+*.dylib                      binary
+/build/bootstrap/*           binary
+/usr/share/terminfo/*        binary
+/usr/share/terminfo/*/*      binary
 /usr/share/zoneinfo/*        binary
+/usr/share/zoneinfo/*/*      binary
@@ -0,0 +1,59 @@
+name: Low Severity Bugs
+description: Used to report low severity bugs in cosmopolitan (e.g. cosmetic issues, non critical UI glitches)
+title: "Bug: "
+labels: ["bug", "low severity"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to fill out this bug report! 
+        Please include information about your system, the steps to reproduce the bug, 
+        and the version of cosmopolitan that you are using. 
+        If possible, please provide a minimal code example that reproduces the bug.
+        You may also consider using function call tracing `--ftrace` or the lighter system call tracing `--strace`
+        for additional technical logging that may allow us to narrow down where the fault occurred.
+  - type: input
+    id: contact
+    attributes:
+      label: Contact Details
+      description: How can we get in touch with you if we need more info?
+      placeholder: ex. [email protected]
+    validations:
+      required: false
+  - type: textarea
+    id: what-happened
+    attributes:
+      label: What happened?
+      description: Also tell us, what did you expect to happen?
+      placeholder: Tell us what you see!
+    validations:
+      required: true
+  - type: textarea
+    id: version
+    attributes:
+      label: Version
+      description: What version of our software are you running? (use `--version` to get a version string)
+      placeholder: "cosmocc (GCC) 12.3.0"
+    validations:
+      required: true
+  - type: dropdown
+    id: operating-system
+    attributes:
+      label: What operating system are you seeing the problem on?
+      multiple: true
+      options:
+        - Linux
+        - Mac
+        - Windows
+        - FreeBSD
+        - OpenBSD
+        - NetBSD
+        - BIOS
+    validations:
+      required: false
+  - type: textarea
+    id: logs
+    attributes:
+      label: Relevant log output
+      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
+      render: shell
@@ -0,0 +1,59 @@
+name: Medium Severity Bug
+description: Used to report medium severity bugs in cosmopolitan (e.g. Malfunctioning Features but generally still useable)
+title: "Bug: "
+labels: ["bug", "medium severity"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to fill out this bug report! 
+        Please include information about your system, the steps to reproduce the bug, 
+        and the version of cosmopolitan that you are using. 
+        If possible, please provide a minimal code example that reproduces the bug.
+        You may also consider using function call tracing `--ftrace` or the lighter system call tracing `--strace`
+        for additional technical logging that may allow us to narrow down where the fault occurred.
+  - type: input
+    id: contact
+    attributes:
+      label: Contact Details
+      description: How can we get in touch with you if we need more info?
+      placeholder: ex. [email protected]
+    validations:
+      required: false
+  - type: textarea
+    id: what-happened
+    attributes:
+      label: What happened?
+      description: Also tell us, what did you expect to happen?
+      placeholder: Tell us what you see!
+    validations:
+      required: true
+  - type: textarea
+    id: version
+    attributes:
+      label: Version
+      description: What version of our software are you running? (use `--version` to get a version string)
+      placeholder: "cosmocc (GCC) 12.3.0"
+    validations:
+      required: true
+  - type: dropdown
+    id: operating-system
+    attributes:
+      label: What operating system are you seeing the problem on?
+      multiple: true
+      options:
+        - Linux
+        - Mac
+        - Windows
+        - FreeBSD
+        - OpenBSD
+        - NetBSD
+        - BIOS
+    validations:
+      required: false
+  - type: textarea
+    id: logs
+    attributes:
+      label: Relevant log output
+      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
+      render: shell
@@ -0,0 +1,59 @@
+name: High Severity Bug
+description: Used to report high severity bugs in cosmopolitan (e.g. Malfunctioning features hindering important common workflow)
+title: "Bug: "
+labels: ["bug", "high severity"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to fill out this bug report! 
+        Please include information about your system, the steps to reproduce the bug, 
+        and the version of cosmopolitan that you are using. 
+        If possible, please provide a minimal code example that reproduces the bug.
+        You may also consider using function call tracing `--ftrace` or the lighter system call tracing `--strace`
+        for additional technical logging that may allow us to narrow down where the fault occurred.
+  - type: input
+    id: contact
+    attributes:
+      label: Contact Details
+      description: How can we get in touch with you if we need more info?
+      placeholder: ex. [email protected]
+    validations:
+      required: false
+  - type: textarea
+    id: what-happened
+    attributes:
+      label: What happened?
+      description: Also tell us, what did you expect to happen?
+      placeholder: Tell us what you see!
+    validations:
+      required: true
+  - type: textarea
+    id: version
+    attributes:
+      label: Version
+      description: What version of our software are you running? (use `--version` to get a version string)
+      placeholder: "cosmocc (GCC) 12.3.0"
+    validations:
+      required: true
+  - type: dropdown
+    id: operating-system
+    attributes:
+      label: What operating system are you seeing the problem on?
+      multiple: true
+      options:
+        - Linux
+        - Mac
+        - Windows
+        - FreeBSD
+        - OpenBSD
+        - NetBSD
+        - BIOS
+    validations:
+      required: false
+  - type: textarea
+    id: logs
+    attributes:
+      label: Relevant log output
+      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
+      render: shell
@@ -0,0 +1,59 @@
+name: Critical Severity Bug
+description: Used to report critical severity bugs in cosmopolitan (e.g. Crashing, Corrupted, Dataloss)
+title: "Bug: "
+labels: ["bug", "critical severity"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to fill out this bug report! 
+        Please include information about your system, the steps to reproduce the bug, 
+        and the version of cosmopolitan that you are using. 
+        If possible, please provide a minimal code example that reproduces the bug.
+        You may also consider using function call tracing `--ftrace` or the lighter system call tracing `--strace`
+        for additional technical logging that may allow us to narrow down where the fault occurred.
+  - type: input
+    id: contact
+    attributes:
+      label: Contact Details
+      description: How can we get in touch with you if we need more info?
+      placeholder: ex. [email protected]
+    validations:
+      required: false
+  - type: textarea
+    id: what-happened
+    attributes:
+      label: What happened?
+      description: Also tell us, what did you expect to happen?
+      placeholder: Tell us what you see!
+    validations:
+      required: true
+  - type: textarea
+    id: version
+    attributes:
+      label: Version
+      description: What version of our software are you running? (use `--version` to get a version string)
+      placeholder: "cosmocc (GCC) 12.3.0"
+    validations:
+      required: true
+  - type: dropdown
+    id: operating-system
+    attributes:
+      label: What operating system are you seeing the problem on?
+      multiple: true
+      options:
+        - Linux
+        - Mac
+        - Windows
+        - FreeBSD
+        - OpenBSD
+        - NetBSD
+        - BIOS
+    validations:
+      required: false
+  - type: textarea
+    id: logs
+    attributes:
+      label: Relevant log output
+      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
+      render: shell
@@ -0,0 +1,51 @@
+name: Enhancement template
+description: Used to request enhancements for cosmopolitan
+title: "Feature Request: "
+labels: ["enhancement"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        [Please post your idea first in Discussion if there is not yet a consensus for this enhancement request. This will help to keep this issue tracker focused on enhancements that the community has agreed needs to be implemented.](https://github.com/jart/cosmopolitan/discussions/categories/ideas)
+
+  - type: checkboxes
+    id: prerequisites
+    attributes:
+      label: Prerequisites
+      description: Please confirm the following before submitting your enhancement request.
+      options:
+        - label: I am running the latest code. Mention the version if possible as well.
+          required: true
+        - label: I carefully followed the [README.md](https://github.com/jart/cosmopolitan/blob/master/README.md).
+          required: true
+        - label: I searched using keywords relevant to my issue to make sure that I am creating a new issue that is not already open (or closed).
+          required: true
+        - label: I reviewed the [Discussions](https://github.com/jart/cosmopolitan/discussions), and have a new and useful enhancement to share.
+          required: true
+
+  - type: textarea
+    id: feature-description
+    attributes:
+      label: Feature Description
+      description: Please provide a detailed written description of what you were trying to do, and what you expected `cosmopolitan` to do as an enhancement.
+      placeholder: Detailed description of the enhancement
+    validations:
+      required: true
+
+  - type: textarea
+    id: motivation
+    attributes:
+      label: Motivation
+      description: Please provide a detailed written description of reasons why this feature is necessary and how it is useful to `cosmopolitan` users.
+      placeholder: Explanation of why this feature is needed and its benefits
+    validations:
+      required: true
+
+  - type: textarea
+    id: possible-implementation
+    attributes:
+      label: Possible Implementation
+      description: If you have an idea as to how it can be implemented, please write a detailed description. Feel free to give links to external sources or share visuals that might be helpful to understand the details better.
+      placeholder: Detailed description of potential implementation
+    validations:
+      required: false
@@ -0,0 +1,52 @@
+name: Research
+description: Track new technical research area
+title: "Research: "
+labels: ["research"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Don't forget to check for any [duplicate research issue tickets](https://github.com/jart/cosmopolitan/issues?q=is%3Aopen+is%3Aissue+label%3A%22research+%F0%9F%94%AC%22)
+
+  - type: checkboxes
+    id: research-stage
+    attributes:
+      label: Research Stage
+      description: Track general state of this research ticket
+      options:
+        - label: Background Research (Let's try to avoid reinventing the wheel)
+        - label: Hypothesis Formed (How do you think this will work and it's effect?)
+        - label: Strategy / Implementation Forming
+        - label: Analysis of results
+        - label: Debrief / Documentation (So people in the future can learn from us)
+
+  - type: textarea
+    id: background
+    attributes:
+      label: Previous existing literature and research
+      description: Whats the current state of the art and whats the motivation for this research?
+
+  - type: textarea
+    id: hypothesis
+    attributes:
+      label: Hypothesis
+      description: How do you think this will work and it's effect?
+
+  - type: textarea
+    id: implementation
+    attributes:
+      label: Implementation
+      description: Got an approach? e.g. a PR ready to go?
+
+  - type: textarea
+    id: analysis
+    attributes:
+      label: Analysis
+      description: How does the proposed implementation behave?
+
+  - type: textarea
+    id: logs
+    attributes:
+      label: Relevant log output
+      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
+      render: shell
@@ -0,0 +1,28 @@
+name: Refactor (Maintainers)
+description: Used to track refactoring opportunities
+title: "Refactor: "
+labels: ["refactor"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Don't forget to [check for existing refactor issue tickets](https://github.com/jart/cosmopolitan/issues?q=is%3Aopen+is%3Aissue+label%3Arefactoring) in case it's already covered.
+        Also you may want to check [Pull request refactor label as well](https://github.com/jart/cosmopolitan/pulls?q=is%3Aopen+is%3Apr+label%3Arefactoring) for duplicates too.
+
+  - type: textarea
+    id: background-description
+    attributes:
+      label: Background Description
+      description: Please provide a detailed written description of the pain points you are trying to solve.
+      placeholder: Detailed description behind your motivation to request refactor
+    validations:
+      required: true
+
+  - type: textarea
+    id: possible-approaches
+    attributes:
+      label: Possible Refactor Approaches
+      description: If you have some idea of possible approaches to solve this problem. You may want to make it a todo list.
+      placeholder: Your idea of possible refactoring opportunity/approaches
+    validations:
+      required: false
@@ -0,0 +1,15 @@
+blank_issues_enabled: true
+contact_links:
+  - name: FAQ
+    url: https://github.com/jart/cosmopolitan/wiki/FAQ
+    about: Is your question a common one? You may want to check here first.
+  - name: Got an idea?
+    url: https://github.com/jart/cosmopolitan/discussions/categories/ideas
+    about: Pop it there. It may then become an enhancement ticket.
+  - name: Got a question?
+    url: https://github.com/jart/cosmopolitan/discussions/categories/q-a
+    about: Ask a question there!
+  - name: Want to contribute?
+    url: https://github.com/jart/cosmopolitan/wiki/contribute
+    about: Head to the contribution guide page of the wiki for areas you can help with
+
@@ -0,0 +1,49 @@
+# https://github.com/actions/labeler
+
+documentation:
+    - changed-files:
+        - any-glob-to-any-file:
+            - README.md
+            - LICENSE
+            - CONTRIBUTING.md
+            - libc/README.md
+            - tool/cosmocc/README.md
+            - third_party/getopt/README.txt
+build:
+    - changed-files:
+        - any-glob-to-any-file:
+            - build/**
+            - Makefile
+            - '*/*.mk'
+examples:
+    - changed-files:
+        - any-glob-to-any-file: examples/**
+devops:
+    - changed-files:
+        - any-glob-to-any-file:
+            - .github/**
+            - .clang-format
+dsp:
+    - changed-files:
+        - any-glob-to-any-file:
+            - dsp/**
+ape:
+    - changed-files:
+        - any-glob-to-any-file:
+            - ape/**
+libc:
+    - changed-files:
+        - any-glob-to-any-file:
+            - libc/**
+net:
+    - changed-files:
+        - any-glob-to-any-file:
+            - net/**
+third_party:
+    - changed-files:
+        - any-glob-to-any-file:
+            - third_party/**
+tool:
+    - changed-files:
+        - any-glob-to-any-file:
+            - tool/**
@@ -0,0 +1,17 @@
+name: "Pull Request Labeler"
+on:
+- pull_request_target
+
+jobs:
+  labeler:
+    permissions:
+      contents: read
+      pull-requests: write
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        repository: "jart/cosmopolitan"
+    - uses: actions/labeler@v5
+      with:
+        configuration-path: '.github/labeler.yml'
@@ -0,0 +1,24 @@
+name: Nightly cosmocc
+on:
+  schedule:
+    # https://crontab.guru/#37_4_*_*_*
+    - cron: "37 4 * * *"
+  workflow_dispatch:
+concurrency:
+  group: ${{ github.workflow }}
+  cancel-in-progress: true
+jobs:
+  build-cosmocc:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: |
+          sudo cp build/bootstrap/ape.elf /usr/bin/ape
+          sudo sh -c "echo ':APE:M::MZqFpD::/usr/bin/ape:' >/proc/sys/fs/binfmt_misc/register"
+      - run: tool/cosmocc/package.sh
+      # https://github.com/actions/upload-artifact/issues/590
+      - uses: actions/[email protected]
+        with:
+          name: cosmocc
+          path: cosmocc
+          compression-level: 9
@@ -0,0 +1,36 @@
+{
+    "C_Cpp.default.compilerPath": ".cosmocc/3.9.2/bin/aarch64-linux-cosmo-c++",
+    "C_Cpp.default.compilerArgs": [
+        "-nostdinc",
+        "-nostdlib",
+        "-iquote.",
+        "-isystemlibc/isystem",
+        "-isystemthird_party/libcxx",
+        "-includelibc/integral/normalize.inc",
+        "-D_COSMO_SOURCE",
+        "-D__aarch64__"
+    ],
+    "[c]": {
+        "editor.tabSize": 2,
+        "editor.insertSpaces": true
+    },
+    "[cpp]": {
+        "editor.tabSize": 2,
+        "editor.insertSpaces": true
+    },
+    "[makefile]": {
+        "editor.tabSize": 8,
+        "editor.insertSpaces": false
+    },
+    "[make]": {
+        "editor.tabSize": 8,
+        "editor.insertSpaces": false
+    },
+    "[assembly]": {
+        "editor.tabSize": 8,
+        "editor.insertSpaces": true
+    },
+    "files.associations": {
+        "log.h": "c"
+    }
+}
@@ -101,23 +101,22 @@ XARGS ?= xargs -P4 -rs8000
 DOT ?= dot
 CLANG = clang
 TMPDIR = o/tmp
-AR = build/bootstrap/ar
-CP = build/bootstrap/cp
-RM = build/bootstrap/rm -f
-GZIP = build/bootstrap/gzip
-ECHO = build/bootstrap/echo
-CHMOD = build/bootstrap/chmod
-TOUCH = build/bootstrap/touch
-PKG = build/bootstrap/package
-MKDEPS = build/bootstrap/mkdeps
-ZIPOBJ = build/bootstrap/zipobj
-ZIPCOPY = build/bootstrap/zipcopy
-PECHECK = build/bootstrap/pecheck
-FIXUPOBJ = build/bootstrap/fixupobj
-MKDIR = build/bootstrap/mkdir -p
-COMPILE = build/bootstrap/compile -V9 -M2048m -P8192 $(QUOTA)
-
-IGNORE := $(shell $(MKDIR) $(TMPDIR))
+AR = $(BOOTSTRAP)/ar.ape
+CP = $(BOOTSTRAP)/cp.ape
+RM = $(BOOTSTRAP)/rm.ape -f
+GZIP = $(BOOTSTRAP)/gzip.ape
+ECHO = $(BOOTSTRAP)/echo.ape
+CHMOD = $(BOOTSTRAP)/chmod.ape
+TOUCH = $(BOOTSTRAP)/touch.ape
+PKG = $(BOOTSTRAP)/package.ape
+MKDEPS = $(BOOTSTRAP)/mkdeps
+ZIPOBJ = $(BOOTSTRAP)/zipobj
+ZIPCOPY = $(BOOTSTRAP)/zipcopy
+PECHECK = $(BOOTSTRAP)/pecheck
+FIXUPOBJ = $(BOOTSTRAP)/fixupobj
+OBJBINCOPY = $(BOOTSTRAP)/objbincopy
+MKDIR = $(BOOTSTRAP)/mkdir.ape -p
+COMPILE = $(BOOTSTRAP)/compile.ape -V9 -M2048m -P8192 $(QUOTA)

 # the default build modes is empty string
 # on x86_64 hosts, MODE= is the same as MODE=x86_64
@@ -133,14 +132,13 @@ endif

 ifneq ($(findstring aarch64,$(MODE)),)
 ARCH = aarch64
-HOSTS ?= pi studio freebsdarm
+HOSTS ?= pi pi5 studio freebsdarm
 else
 ARCH = x86_64
 HOSTS ?= freebsd rhel7 xnu openbsd netbsd win10
 endif

 ZIPOBJ_FLAGS += -a$(ARCH)
-IGNORE := $(shell $(MKDIR) $(TMPDIR))

 export ADDR2LINE
 export LC_ALL
@@ -149,9 +147,12 @@ export MODE
 export SOURCE_DATE_EPOCH
 export TMPDIR

-COSMOCC = .cosmocc/3.3.5
+COSMOCC = .cosmocc/3.9.2
+BOOTSTRAP = $(COSMOCC)/bin
 TOOLCHAIN = $(COSMOCC)/bin/$(ARCH)-linux-cosmo-
-DOWNLOAD := $(shell build/download-cosmocc.sh $(COSMOCC) 3.3.5 db78fd8d3f8706e9dff4be72bf71d37a3f12062f212f407e1c33bc4af3780dd0)
+DOWNLOAD := $(shell build/download-cosmocc.sh $(COSMOCC) 3.9.2 f4ff13af65fcd309f3f1cfd04275996fb7f72a4897726628a8c9cf732e850193)
+
+IGNORE := $(shell $(MKDIR) $(TMPDIR))

 AS = $(TOOLCHAIN)as
 CC = $(TOOLCHAIN)gcc
@@ -256,7 +257,6 @@ include third_party/nsync/mem/BUILD.mk		# │  You can now use stdio
 include libc/proc/BUILD.mk			# │  You can now use threads
 include libc/dlopen/BUILD.mk			# │  You can now use processes
 include libc/thread/BUILD.mk			# │  You can finally call malloc()
-include ctl/BUILD.mk				# │
 include third_party/zlib/BUILD.mk		# │
 include libc/stdio/BUILD.mk			# │
 include tool/hello/BUILD.mk			# │
@@ -278,6 +278,8 @@ include libc/x/BUILD.mk				# │
 include dsp/scale/BUILD.mk			# │
 include dsp/mpeg/BUILD.mk			# │
 include dsp/tty/BUILD.mk			# │
+include dsp/audio/BUILD.mk			# │
+include dsp/prog/BUILD.mk			# │
 include dsp/BUILD.mk				# │
 include third_party/stb/BUILD.mk		# │
 include third_party/mbedtls/BUILD.mk		# │
@@ -285,14 +287,14 @@ include third_party/ncurses/BUILD.mk		# │
 include third_party/readline/BUILD.mk		# │
 include third_party/libunwind/BUILD.mk		# |
 include third_party/libcxxabi/BUILD.mk		# |
+include third_party/double-conversion/BUILD.mk	# │
+include ctl/BUILD.mk				# │
 include third_party/libcxx/BUILD.mk		# │
 include third_party/openmp/BUILD.mk		# │
-include third_party/double-conversion/BUILD.mk	# │
 include third_party/pcre/BUILD.mk		# │
 include third_party/less/BUILD.mk		# │
 include net/https/BUILD.mk			# │
-include third_party/regex/BUILD.mk		# │
-include third_party/bash/BUILD.mk		#─┘
+include third_party/regex/BUILD.mk		#─┘
 include third_party/tidy/BUILD.mk
 include third_party/BUILD.mk
 include third_party/nsync/testing/BUILD.mk
@@ -428,67 +430,69 @@ HTAGS:	o/$(MODE)/hdrs-old.txt $(filter-out third_party/libcxx/%,$(HDRS)) #o/$(MO

 loc: private .UNSANDBOXED = 1
 loc: o/$(MODE)/tool/build/summy
-	find -name \*.h -or -name \*.c -or -name \*.S | \
+	find -name \*.h -or -name \*.hpp -or -name \*.c -or -name \*.cc -or -name \*.cpp -or -name \*.S -or -name \*.mk | \
 	$(XARGS) wc -l | grep total | awk '{print $$1}' | $<

-# PLEASE: MAINTAIN TOPOLOGICAL ORDER
-# FROM HIGHEST LEVEL TO LOWEST LEVEL
-COSMOPOLITAN_OBJECTS =			\
-	TOOL_ARGS			\
-	NET_HTTP			\
-	LIBC_SOCK			\
-	LIBC_NT_WS2_32			\
-	LIBC_NT_IPHLPAPI		\
-	LIBC_X				\
-	THIRD_PARTY_GETOPT		\
-	LIBC_LOG			\
-	THIRD_PARTY_TZ			\
-	THIRD_PARTY_OPENMP		\
-	THIRD_PARTY_MUSL		\
-	THIRD_PARTY_ZLIB_GZ		\
-	THIRD_PARTY_LIBCXXABI		\
-	THIRD_PARTY_LIBUNWIND		\
-	LIBC_STDIO			\
-	THIRD_PARTY_GDTOA		\
-	THIRD_PARTY_REGEX		\
-	LIBC_THREAD			\
-	LIBC_PROC			\
-	THIRD_PARTY_NSYNC_MEM		\
+COSMOPOLITAN =				\
 	CTL				\
-	LIBC_MEM			\
-	THIRD_PARTY_DLMALLOC		\
-	LIBC_DLOPEN			\
-	LIBC_RUNTIME			\
-	THIRD_PARTY_NSYNC		\
-	LIBC_ELF			\
-	LIBC_IRQ			\
+	DSP_AUDIO			\
 	LIBC_CALLS			\
-	LIBC_SYSV_CALLS			\
-	LIBC_VGA			\
-	LIBC_NT_PSAPI			\
-	LIBC_NT_POWRPROF		\
-	LIBC_NT_PDH			\
-	LIBC_NT_GDI32			\
-	LIBC_NT_COMDLG32		\
-	LIBC_NT_USER32			\
-	LIBC_NT_NTDLL			\
-	LIBC_NT_ADVAPI32		\
-	LIBC_NT_SYNCHRONIZATION		\
+	LIBC_DLOPEN			\
+	LIBC_ELF			\
 	LIBC_FMT			\
-	THIRD_PARTY_ZLIB		\
-	THIRD_PARTY_PUFF		\
-	THIRD_PARTY_COMPILER_RT		\
-	LIBC_TINYMATH			\
-	THIRD_PARTY_XED			\
+	LIBC_INTRIN			\
+	LIBC_IRQ			\
+	LIBC_LOG			\
+	LIBC_MEM			\
+	LIBC_NEXGEN32E			\
+	LIBC_NT_ADVAPI32		\
+	LIBC_NT_BCRYPTPRIMITIVES	\
+	LIBC_NT_COMDLG32		\
+	LIBC_NT_GDI32			\
+	LIBC_NT_IPHLPAPI		\
+	LIBC_NT_KERNEL32		\
+	LIBC_NT_NTDLL			\
+	LIBC_NT_PDH			\
+	LIBC_NT_POWRPROF		\
+	LIBC_NT_PSAPI			\
+	LIBC_NT_REALTIME		\
+	LIBC_NT_SYNCHRONIZATION		\
+	LIBC_NT_USER32			\
+	LIBC_NT_WS2_32			\
+	LIBC_PROC			\
+	LIBC_RUNTIME			\
+	LIBC_SOCK			\
+	LIBC_STDIO			\
 	LIBC_STR			\
 	LIBC_SYSV			\
-	LIBC_INTRIN			\
-	LIBC_NT_BCRYPTPRIMITIVES	\
-	LIBC_NT_KERNEL32		\
-	LIBC_NEXGEN32E
+	LIBC_SYSV_CALLS			\
+	LIBC_THREAD			\
+	LIBC_TINYMATH			\
+	LIBC_VGA			\
+	LIBC_X				\
+	NET_HTTP			\
+	THIRD_PARTY_COMPILER_RT		\
+	THIRD_PARTY_DLMALLOC		\
+	THIRD_PARTY_DOUBLECONVERSION	\
+	THIRD_PARTY_GDTOA		\
+	THIRD_PARTY_GETOPT		\
+	THIRD_PARTY_LIBCXXABI		\
+	THIRD_PARTY_LIBUNWIND		\
+	THIRD_PARTY_MUSL		\
+	THIRD_PARTY_NSYNC		\
+	THIRD_PARTY_NSYNC_MEM		\
+	THIRD_PARTY_OPENMP		\
+	THIRD_PARTY_PUFF		\
+	THIRD_PARTY_REGEX		\
+	THIRD_PARTY_TZ			\
+	THIRD_PARTY_XED			\
+	THIRD_PARTY_ZLIB		\
+	THIRD_PARTY_ZLIB_GZ		\
+	TOOL_ARGS			\

 COSMOPOLITAN_H_PKGS =			\
 	APE				\
+	DSP_AUDIO			\
 	LIBC				\
 	LIBC_CALLS			\
 	LIBC_ELF			\
@@ -532,14 +536,14 @@ COSMOCC_PKGS =				\
 	THIRD_PARTY_INTEL

 o/$(MODE)/cosmopolitan.a:		\
-		$(foreach x,$(COSMOPOLITAN_OBJECTS),$($(x)_A_OBJS))
+		$(call uniq,$(foreach x,$(COSMOPOLITAN),$($(x))))

 COSMOCC_HDRS =								\
 	$(wildcard libc/integral/*)					\
 	$(foreach x,$(COSMOCC_PKGS),$($(x)_HDRS))			\
 	$(foreach x,$(COSMOCC_PKGS),$($(x)_INCS))

-o/cosmocc.h.txt: Makefile
+o/cosmocc.h.txt: Makefile libc $(MAKEFILES) $(call uniq,$(foreach x,$(HDRS) $(INCS),$(dir $(x)))) $(HDRS) $(INCS)
 	$(file >$@, $(call uniq,$(COSMOCC_HDRS)))

 COSMOPOLITAN_H_ROOT_HDRS =						\
@@ -244,7 +244,7 @@ server. You're welcome to join us! <https://discord.gg/FwAVVu7eJ4>

 | Platform       | Min Version | Circa |
 | :---           | ---:        | ---:  |
-| AMD            | K8 Venus    | 2005  |
+| AMD            | K8          | 2003  |
 | Intel          | Core        | 2006  |
 | Linux          | 2.6.18      | 2007  |
 | Windows        | 8 [1]       | 2012  |
@@ -45,10 +45,10 @@ o/$(MODE)/ape: $(APE)

 o/$(MODE)/ape/aarch64.lds:			\
 	ape/aarch64.lds				\
-	libc/zip.internal.h			\
+	libc/zip.h				\
 	libc/thread/tls.h			\
 	libc/calls/struct/timespec.h		\
-	libc/macros.internal.h			\
+	libc/macros.h				\
 	libc/str/str.h

 APE_LOADER_LDFLAGS =				\
@@ -162,9 +162,8 @@ o/$(MODE)/ape/ape-no-modify-self.o:		\
 		libc/dce.h			\
 		libc/elf/def.h			\
 		libc/thread/tls.h		\
-		libc/intrin/asancodes.h		\
-		libc/macho.internal.h		\
-		libc/macros.internal.h		\
+		libc/macho.h			\
+		libc/macros.h			\
 		libc/nexgen32e/uart.internal.h	\
 		libc/calls/metalfile.internal.h	\
 		libc/nt/pedef.internal.h	\
@@ -189,9 +188,8 @@ o/$(MODE)/ape/ape-copy-self.o:			\
 		libc/dce.h			\
 		libc/elf/def.h			\
 		libc/thread/tls.h		\
-		libc/intrin/asancodes.h		\
-		libc/macho.internal.h		\
-		libc/macros.internal.h		\
+		libc/macho.h			\
+		libc/macros.h			\
 		libc/nexgen32e/uart.internal.h	\
 		libc/calls/metalfile.internal.h	\
 		libc/nt/pedef.internal.h	\
@@ -220,10 +218,10 @@ o/$(MODE)/ape/loader-xnu-clang.asm: ape/loader.c
 	@$(COMPILE) -AOBJECTIFY.c $(CLANG) -DSUPPORT_VECTOR=8 -S -g0 $(APE_LOADER_FLAGS)

 o/$(MODE)/ape/ape.elf: o/$(MODE)/ape/ape.elf.dbg
-	@$(COMPILE) -AOBJBINCOPY -w build/bootstrap/objbincopy -f -o $@ $<
+	@$(COMPILE) -AOBJBINCOPY -w $(OBJBINCOPY) -f -o $@ $<

 o/$(MODE)/ape/ape.macho: o/$(MODE)/ape/ape.elf.dbg
-	@$(COMPILE) -AOBJBINCOPY -w build/bootstrap/objbincopy -fm -o $@ $<
+	@$(COMPILE) -AOBJBINCOPY -w $(OBJBINCOPY) -fm -o $@ $<

 APE_LOADER_LDFLAGS =				\
 	-static					\
@@ -248,8 +246,6 @@ o/$(MODE)/ape:	$(APE_CHECKS)			\
 		o/$(MODE)/ape/ape.lds		\
 		o/$(MODE)/ape/ape.elf		\
 		o/$(MODE)/ape/ape.macho		\
-		o/$(MODE)/ape/ape-copy-self.o	\
-		o/$(MODE)/ape/ape-no-modify-self.o

 endif

@@ -263,8 +259,8 @@ o/$(MODE)/ape/ape.o:				\
 		libc/thread/tls.h		\
 		ape/ape.internal.h		\
 		ape/macros.internal.h		\
-		libc/macho.internal.h		\
-		libc/macros.internal.h		\
+		libc/macho.h			\
+		libc/macros.h			\
 		libc/sysv/consts/prot.h		\
 		libc/nt/pedef.internal.h	\
 		libc/runtime/pc.internal.h	\
@@ -285,7 +281,7 @@ o/$(MODE)/ape/ape.lds:				\
 		libc/dce.h			\
 		libc/elf/def.h			\
 		libc/elf/pf2prot.internal.h	\
-		libc/macros.internal.h		\
+		libc/macros.h			\
 		libc/nt/pedef.internal.h	\
 		libc/str/str.h			\
-		libc/zip.internal.h
+		libc/zip.h
@@ -1,6 +1,7 @@
 /*-*- mode: ld-script; indent-tabs-mode: nil; tab-width: 2; coding: utf-8   -*-│
 │ vi: set et sts=2 sw=2 fenc=utf-8                                         :vi │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/sysv/consts/prot.h"
 #include "libc/thread/tls.h"

 ENTRY(_start)
@@ -11,7 +12,7 @@ OUTPUT_FORMAT("elf64-littleaarch64",

 SECTIONS {

-  . = SEGMENT_START("text-segment", 0x010000000000);
+  . = SEGMENT_START("text-segment", 0x000800000000);
  __executable_start = .;
  . += SIZEOF_HEADERS;

@@ -102,10 +103,8 @@ SECTIONS {
    *(.eh_frame_entry .eh_frame_entry.*)
  }

-  .eh_frame : ONLY_IF_RO {
-    KEEP(*(.eh_frame))
-    *(.eh_frame.*)
-  }
+  __eh_frame_hdr_start = SIZEOF(.eh_frame_hdr) > 0 ? ADDR(.eh_frame_hdr) : 0;
+  __eh_frame_hdr_end = SIZEOF(.eh_frame_hdr) > 0 ? . : 0;

  .gcc_except_table : ONLY_IF_RO {
    *(.gcc_except_table .gcc_except_table.*)
@@ -126,9 +125,11 @@ SECTIONS {
  . += CONSTANT(MAXPAGESIZE);
  . = DATA_SEGMENT_ALIGN(CONSTANT(MAXPAGESIZE), CONSTANT(COMMONPAGESIZE));

-  .eh_frame : ONLY_IF_RW {
+  .eh_frame : {
+    __eh_frame_start = .;
    KEEP(*(.eh_frame))
    *(.eh_frame.*)
+    __eh_frame_end = .;
  }

  .gnu_extab : ONLY_IF_RW {
@@ -285,8 +286,7 @@ SECTIONS {

 ape_stack_vaddr = DEFINED(ape_stack_vaddr) ? ape_stack_vaddr : 0x700000000000;
 ape_stack_memsz = DEFINED(ape_stack_memsz) ? ape_stack_memsz : 8 * 1024 * 1024;
-ape_stack_align = DEFINED(ape_stack_align) ? ape_stack_align : 16;
-ape_stack_round = -ape_stack_align;
+ape_stack_prot = PROT_READ | PROT_WRITE;

 _tls_size = _tbss_end - _tdata_start;
 _tdata_size = _tdata_end - _tdata_start;
@@ -16,6 +16,12 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#ifndef __APPLE__
+#error "ape/ape-m1.c is for apple silicon. chances you want ape/loader.c"
+#endif
+#ifndef __aarch64__
+#error "ape/ape-m1.c is for apple silicon; you want: make o//ape/ape.macho"
+#endif
 #include <assert.h>
 #include <dispatch/dispatch.h>
 #include <dlfcn.h>
@@ -37,7 +37,7 @@
 #include "libc/calls/metalfile.internal.h"
 #include "libc/dce.h"
 #include "libc/elf/def.h"
-#include "libc/macho.internal.h"
+#include "libc/macho.h"
 #include "libc/nexgen32e/uart.internal.h"
 #include "libc/nt/pedef.internal.h"
 #include "libc/runtime/pc.internal.h"
@@ -761,7 +761,7 @@ ape_phdrs:
 	.quad	0
 	.quad	0
 	.quad	0
-	.stub	ape_stack_align,quad
+	.quad	16

 #if SupportsOpenbsd() || SupportsNetbsd()
 	.long	PT_NOTE
@@ -310,7 +310,7 @@ SECTIONS {
    . = ALIGN(__privileged_end > __privileged_start ? CONSTANT(COMMONPAGESIZE) : 0);
 /*END: morphable code */
    __privileged_start = .;
-    *(.privileged)
+    *(.privileged .privileged.*)
    __privileged_end = .;

    KEEP(*(.ape.pad.text))
@@ -329,6 +329,10 @@ SECTIONS {
    *(.ubsan.types)
    *(.ubsan.data)

+    __eh_frame_hdr_start_actual = .;
+    *(.eh_frame_hdr)
+    __eh_frame_hdr_end_actual = .;
+
    /* Legal Notices */
    __notices = .;
    KEEP(*(.notice))
@@ -422,6 +426,11 @@ SECTIONS {
    KEEP(*(.dtors))
    __fini_array_end = .;

+    __eh_frame_start = .;
+    KEEP(*(.eh_frame))
+    *(.eh_frame.*)
+    __eh_frame_end = .;
+
 /*BEGIN: Post-Initialization Read-Only */
    . = ALIGN(. != 0 ? __SIZEOF_POINTER__ : 0);
    KEEP(*(SORT_BY_NAME(.piro.relo.sort.*)))
@@ -588,8 +597,6 @@ ape_stack_vaddr = DEFINED(ape_stack_vaddr) ? ape_stack_vaddr : 0x700000000000;
 ape_stack_paddr = ape_ram_paddr + ape_ram_filesz;
 ape_stack_filesz = 0;
 ape_stack_memsz = DEFINED(ape_stack_memsz) ? ape_stack_memsz : 8 * 1024 * 1024;
-ape_stack_align = DEFINED(ape_stack_align) ? ape_stack_align : 16;
-ape_stack_round = -ape_stack_align;

 ape_note_offset = ape_cod_offset + (ape_note - ape_cod_vaddr);
 ape_note_filesz = ape_note_end - ape_note;
@@ -603,6 +610,9 @@ ape_text_memsz = ape_text_filesz;
 ape_text_align = CONSTANT(COMMONPAGESIZE);
 ape_text_rva = RVA(ape_text_vaddr);

+__eh_frame_hdr_start = __eh_frame_hdr_end_actual > __eh_frame_hdr_start_actual ? __eh_frame_hdr_start_actual : 0;
+__eh_frame_hdr_end = __eh_frame_hdr_end_actual > __eh_frame_hdr_start_actual ? __eh_frame_hdr_end_actual : 0;
+
 /* we roundup here because xnu wants the file load segments page-aligned */
 /* but we don't want to add the nop padding to the ape program, so we'll */
 /* let ape.S dd read past the end of the file into the wrapping binaries */
@@ -16,7 +16,7 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/macros.internal.h"
+#include "libc/macros.h"

 //	Calls _start() function of loaded program.
 //
@@ -16,10 +16,10 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/macho.internal.h"
+#include "libc/macho.h"
 #include "libc/sysv/consts/prot.h"
 #include "libc/dce.h"
-#include "libc/macros.internal.h"
+#include "libc/macros.h"

 //	Apple Mach-O Executable Headers
 //	Fixups are applied by objbincopy
@@ -18,7 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #ifndef APE_MACROS_H_
 #define APE_MACROS_H_
-#include "libc/macros.internal.h"
+#include "libc/macros.h"
 #ifdef __ASSEMBLER__
 /* clang-format off */

@@ -84,9 +84,10 @@
 /* clang-format on */
 #elif defined(__LINKER__)

-#define BCX_NIBBLE(X) ((((X)&0xf) > 0x9) ? ((X)&0xf) + 0x37 : ((X)&0xf) + 0x30)
-#define BCX_OCTET(X)  ((BCX_NIBBLE((X) >> 4) << 8) | (BCX_NIBBLE((X) >> 0) << 0))
-#define BCX_INT16(X)  ((BCX_OCTET((X) >> 8) << 16) | (BCX_OCTET((X) >> 0) << 0))
+#define BCX_NIBBLE(X) \
+  ((((X) & 0xf) > 0x9) ? ((X) & 0xf) + 0x37 : ((X) & 0xf) + 0x30)
+#define BCX_OCTET(X) ((BCX_NIBBLE((X) >> 4) << 8) | (BCX_NIBBLE((X) >> 0) << 0))
+#define BCX_INT16(X) ((BCX_OCTET((X) >> 8) << 16) | (BCX_OCTET((X) >> 0) << 0))
 #define BCXSTUB(SYM, X)                      \
  HIDDEN(SYM##_bcx0 = BCX_INT16((X) >> 48)); \
  HIDDEN(SYM##_bcx1 = BCX_INT16((X) >> 32)); \
@@ -98,12 +99,12 @@
 *
 * <p>This allows linker scripts to generate printf commands.
 */
-#define BCO_OCTET(X) (((X)&0x7) + 0x30)
+#define BCO_OCTET(X) (((X) & 0x7) + 0x30)
 #define BCOB_UNIT(X)                                           \
  ((BCO_OCTET((X) >> 0) << 24) | (BCO_OCTET((X) >> 3) << 16) | \
-   (BCO_OCTET(((X)&0xff) >> 6) << 8) | 0x5c)
+   (BCO_OCTET(((X) & 0xff) >> 6) << 8) | 0x5c)

-#define PFBYTE(SYM, X, I) HIDDEN(SYM##_bcs##I = BCOB_UNIT((X) >> ((I)*8)))
+#define PFBYTE(SYM, X, I) HIDDEN(SYM##_bcs##I = BCOB_UNIT((X) >> ((I) * 8)))
 #define PFSTUB2(SYM, X) \
  HIDDEN(SYM = (X));    \
  PFBYTE(SYM, X, 0);    \
@@ -132,7 +133,7 @@
 #define SHSTUB2(SYM, X)             \
  HIDDEN(SYM##_bcs0 = BCD_LEFT(X)); \
  HIDDEN(SYM##_bcs1 = BCD_RIGHT(X))
-#define BCD_SMEAR(X) ((X) + (X)*10000)
+#define BCD_SMEAR(X) ((X) + (X) * 10000)
 #define BCD_LEFT(X)                                      \
  (((X)) < 10000     ? BCD_RIGHT(BCD_SMEAR(X)) | 0x10    \
   : (X) < 100000    ? BCD_RIGHT(BCD_SMEAR((X) / 10))    \
@@ -0,0 +1,703 @@
+# Actually Portable Executable Specification v0.1
+
+Actually Portable Executable (APE) is an executable file format that
+polyglots the Windows Portable Executable (PE) format with a UNIX Sixth
+Edition style shell script that doesn't have a shebang. This makes it
+possible to produce a single file binary that executes on the stock
+installations of the many OSes and architectures.
+
+## Supported OSes and Architectures
+
+- AMD64
+  - Linux
+  - MacOS
+  - Windows
+  - FreeBSD
+  - OpenBSD
+  - NetBSD
+  - BIOS
+
+- ARM64
+  - Linux
+  - MacOS
+  - FreeBSD
+  - Windows (non-native)
+
+## File Header
+
+APE defines three separate file magics, all of which are 8 characters
+long. Any file that starts with one of these magic values can be
+considered an APE program.
+
+### (1) APE MZ Magic
+
+- ASCII: `MZqFpD='`
+- Hex: 4d 5a 71 46 70 44 3d 27
+
+This is the canonical magic used by almost all APE programs. It enables
+maximum portability between OSes. When interpreted as a shell script, it
+is assigning a single quoted string to an unused variable. The shell
+will then ignore subsequent binary content that's placed inside the
+string.
+
+It is strongly recommended that this magic value be immediately followed
+by a newline (\n or hex 0a) character. Some shells, e.g. FreeBSD SH and
+Zsh impose a binary safety check before handing off files that don't
+have a shebang to `/bin/sh`. That check applies to the first line, which
+can't contain NUL characters.
+
+The letters were carefully chosen so as to be valid x86 instructions in
+all operating modes. This makes it possible to store a BIOS bootloader
+disk image inside an APE binary. For example, simple CLI programs built
+with Cosmopolitan Libc will boot from BIOS into long mode if they're
+treated as a floppy disk image.
+
+The letters also allow for the possibility of being treated on x86-64 as
+a flat executable, where the PE / ELF / Mach-O executable structures are
+ignored, and execution simply begins at the beginning of the file,
+similar to how MS-DOS .COM binaries work.
+
+The 0x4a relative offset of the magic causes execution to jump into the
+MS-DOS stub defined by Portable Executable. APE binaries built by Cosmo
+Libc use tricks in the MS-DOS stub to check the operating mode and then
+jump to the appropriate entrypoint, e.g. `_start()`.
+
+#### Decoded as i8086
+
+```asm
+  dec  %bp
+  pop  %dx
+  jno  0x4a
+  jo   0x4a
+```
+
+#### Decoded as i386
+
+```asm
+  push %ebp
+  pop  %edx
+  jno  0x4a
+  jo   0x4a
+```
+
+#### Decoded as x86-64
+
+```asm
+  rex.WRB
+  pop %r10
+  jno 0x4a
+  jo  0x4a
+```
+
+### (2) APE UNIX-Only Magic
+
+- ASCII: `jartsr='`
+- Hex: 6a 61 72 74 73 72 3d 27
+
+Being a novel executable format that was first published in 2020, the
+APE file format is less understood by industry tools compared to the PE,
+ELF, and Mach-O executable file formats, which have been around for
+decades. For this reason, APE programs that use the MZ magic above can
+attract attention from Windows AV software, which may be unwanted by
+developers who aren't interested in targeting the Windows platform.
+Therefore the `jartsr='` magic is defined which enables the creation of
+APE binaries that can safely target all non-Windows platforms. Even
+though this magic is less common, APE interpreters and binfmt-misc
+installations MUST support this.
+
+It is strongly recommended that this magic value be immediately followed
+by a newline (\n or hex 0a) character. Some shells, e.g. FreeBSD SH and
+Zsh impose a binary safety check before handing off files that don't
+have a shebang to `/bin/sh`. That check applies to the first line, which
+can't contain NUL characters.
+
+The letters were carefully chosen so as to be valid x86 instructions in
+all operating modes. This makes it possible to store a BIOS bootloader
+disk image inside an APE binary. For example, simple CLI programs built
+with Cosmopolitan Libc will boot from BIOS into long mode if they're
+treated as a floppy disk image.
+
+The letters also allow for the possibility of being treated on x86-64 as
+a flat executable, where the PE / ELF / Mach-O executable structures are
+ignored, and execution simply begins at the beginning of the file,
+similar to how MS-DOS .COM binaries work.
+
+The 0x78 relative offset of the magic causes execution to jump into the
+MS-DOS stub defined by Portable Executable. APE binaries built by Cosmo
+Libc use tricks in the MS-DOS stub to check the operating mode and then
+jump to the appropriate entrypoint, e.g. `_start()`.
+
+#### Decoded as i8086 / i386 / x86-64
+
+```asm
+  push $0x61
+  jb   0x78
+  jae  0x78
+```
+
+### (3) APE Debug Magic
+
+- ASCII: `APEDBG='`
+- Hex: 41 50 45 44 42 47 3d 27
+
+While APE files must be valid shell scripts, in practice, UNIX systems
+will oftentimes be configured to provide a faster safer alternative to
+loading an APE binary through `/bin/sh`. The Linux Kernel can be patched
+to have execve() recognize the APE format and directly load its embedded
+ELF header. Linux systems can also use binfmt-misc to recognize APE's MZ
+and jartsr magic, and pass them to a userspace program named `ape` that
+acts as an interpreter. In such environments, the need sometimes arises
+to be able to test that the `/bin/sh` is working correctly, in which
+case the `APEDBG='` magic is RECOMMENDED.
+
+APE interpreters, execve() implementations, and binfmt-misc installs
+MUST ignore this magic. If necessary, steps can be taken to help files
+with this magic be passed to `/bin/sh` like a normal shebang-less shell
+script for execution.
+
+## Embedded ELF Header
+
+APE binaries MAY embed an ELF header inside them. Unlike conventional
+executable file formats, this header is not stored at a fixed offset.
+It's instead encoded as octal escape codes in a shell script `printf`
+statement. For example:
+
+```
+printf '\177ELF\2\1\1\011\0\0\0\0\0\0\0\0\2\0\076\0\1\0\0\0\166\105\100\000\000\000\000\000\060\013\000\000\000\000\000\000\000\000\000\000\000\000\000\000\165\312\1\1\100\0\070\0\005\000\0\0\000\000\000\000'
+```
+
+This `printf` statement MUST appear in the first 8192 bytes of the APE
+executable, so as to limit how much of the initial portion of a file an
+interpreter must load.
+
+Multiple such `printf` statements MAY appear in the first 8192 bytes, in
+order to specify multiple architectures. For example, fat binaries built
+by the `apelink` program (provided by Cosmo Libc) will have two encoded
+ELF headers, for AMD64 and ARM64, each of which point into the proper
+file offsets for their respective native code. Therefore, kernels and
+interpreters which load the APE format directly MUST check the
+`e_machine` field of the `Elf64_Ehdr` that's decoded from the octal
+codes, before accepting a `printf` shell statement as valid.
+
+These printf statements MUST always use only unescaped ASCII characters
+or octal escape codes. These printf statements MUST NOT use space saving
+escape codes such as `\n`. For example, rather than saying `\n` it would
+be valid to say `\012` instead. It's also valid to say `\12` but only if
+the encoded characters that follow aren't an octal digit.
+
+For example, the following algorithm may be used for parsing octal:
+
+```c
+static int ape_parse_octal(const unsigned char page[8192], int i, int *pc)
+{
+        int c;
+        if ('0' <= page[i] && page[i] <= '7') {
+                c = page[i++] - '0';
+                if ('0' <= page[i] && page[i] <= '7') {
+                        c *= 8;
+                        c += page[i++] - '0';
+                        if ('0' <= page[i] && page[i] <= '7') {
+                                c *= 8;
+                                c += page[i++] - '0';
+                        }
+                }
+                *pc = c;
+        }
+        return i;
+}
+```
+
+APE aware interpreters SHOULD only take `e_machine` into consideration.
+It is the responsibility of the `_start()` function to detect the OS.
+Therefore, multiple `printf` statements are only embedded in the shell
+script for different CPU architectures.
+
+The OS ABI field of an APE embedded `Elf64_Ehdr` SHOULD be set to
+`ELFOSABI_FREEBSD`, since it's the only UNIX OS APE supports that
+actually checks the field. However different values MAY be chosen for
+binaries that don't intend to have FreeBSD in their support vector.
+
+Counter-intuitively, the ARM64 ELF header is used on the MacOS ARM64
+platform when loading from fat binaries.
+
+## Embedded Mach-O Header (x86-64 only)
+
+APE shell scripts that support MacOS on AMD64 must use the `dd` command
+in a very specific way to specify how the embedded binary Macho-O header
+is copied backward to the start of the file. For example:
+
+```
+dd if="$o" of="$o" bs=8 skip=433      count=66       conv=notrunc
+```
+
+These `dd` statements have traditionally been generated by the GNU as
+and ld.bfd programs by encoding ASCII into 64-bit linker relocations,
+which necessitated a fixed width for integer values. It took several
+iterations over APE's history before we eventually got it right:
+
+- `arg="  9293"` is how we originally had ape do it
+- `arg=$((  9293))` b/c busybox sh disliked quoted space
+- `arg=9293  ` is generated by modern apelink program
+
+Software that parses the APE file format, which needs to extract the
+Macho-O x86-64 header SHOULD support the old binaries that use the
+previous encodings. To make backwards compatibility simple the following
+regular expression may be used, which generalizes to all defined
+formats:
+
+```c
+regcomp(&rx,
+        "bs="              // dd block size arg
+        "(['\"] *)?"       //   #1 optional quote w/ space
+        "(\\$\\(\\( *)?"   //   #2 optional math w/ space
+        "([[:digit:]]+)"   //   #3
+        "( *\\)\\))?"      //   #4 optional math w/ space
+        "( *['\"])?"       //   #5 optional quote w/ space
+        " +"               //
+        "skip="            // dd skip arg
+        "(['\"] *)?"       //   #6 optional quote w/ space
+        "(\\$\\(\\( *)?"   //   #7 optional math w/ space
+        "([[:digit:]]+)"   //   #8
+        "( *\\)\\))?"      //   #9 optional math w/ space
+        "( *['\"])?"       //  #10 optional quote w/ space
+        " +"               //
+        "count="           // dd count arg
+        "(['\"] *)?"       //  #11 optional quote w/ space
+        "(\\$\\(\\( *)?"   //  #12 optional math w/ space
+        "([[:digit:]]+)",  //  #13
+        REG_EXTENDED);
+```
+
+For further details, see the canonical implementation in
+`cosmopolitan/tool/build/assimilate.c`.
+
+## Static Linking
+
+Actually Portable Executables are always statically linked. This
+revision of the specification does not define any facility for storing
+code in dynamic shared objects.
+
+Cosmopolitan Libc provides a solution that enables APE binaries have
+limited access to dlopen(). By manually loading a platform-specific
+executable and asking the OS-specific libc's dlopen() to load
+OS-specific libraries, it becomes possible to use GPUs and GUIs. This
+has worked great for AI projects like llamafile.
+
+There is no way for an Actually Portable Executable to interact with
+OS-specific dynamic shared object extension modules to programming
+languages. For example, a Lua interpreter compiled as an Actually
+Portable Executable would have no way of linking extension libraries
+downloaded from the Lua Rocks package manager. This is primarily because
+different OSes define incompatible ABIs.
+
+While it was possible to polyglot PE+ELF+MachO to create multi-OS
+executables, it simply isn't possible to do that same thing for
+DLL+DYLIB+SO. Therefore, in order to have DSOs, APE would need to either
+choose one of the existing formats or invent one of its own, and then
+develop its own parallel ecosystem of extension software. In the future,
+the APE specification may expand to encompass this. However the focus to
+date has been exclusively on executables with limited dlopen() support.
+
+## Application Binary Interface (ABI)
+
+APE binaries use the System V ABI, as defined by:
+
+- [System V ABI - AMD64 Architecture Processor Supplement](https://gitlab.com/x86-psABIs/x86-64-ABI)
+- AARCH64 has a uniform consensus defined by ARM Limited
+
+There are however a few changes we've had to make.
+
+### No Red Zone
+
+Actually Portable Executables that have Windows and/or bare metal in
+their support vector MUST be compiled using `-mno-red-zone`. This is
+because, on Windows, DLLs and other software lurking in the va-space
+might use tricks like SetThreadContext() to take control of a thread
+whereas on bare metal, it's also generally accepted that kernel-mode
+code cannot assume a red zone either due to hardware interrupts that
+pull the exact same kinds of stunts.
+
+APE software that only has truly System V ABI conformant OSes (e.g.
+Linux) in their support vector MAY use the red zone optimization.
+
+### Thread Local Storage
+
+#### aarch64
+
+Here's the TLS memory layout on aarch64:
+
+```
+           x28
+        %tpidr_el0
+            │
+            │    _Thread_local
+        ┌───┼───┬──────────┬──────────┐
+        │tib│dtv│  .tdata  │  .tbss   │
+        ├───┴───┴──────────┴──────────┘
+        │
+    __get_tls()
+```
+
+The ARM64 code in actually portable executables use the `x28` register
+to store the address of the thread information block. All aarch64 code
+linked into these executables SHOULD be compiled with `-ffixed-x28`
+which is supported by both Clang and GCC.
+
+The runtime library for an actually portable executables MAY choose to
+use `tpidr_el0` instead, if OSes like MacOS aren't being targeted. For
+example, if the goal is to create a Linux-only fat binary linker program
+for Musl Libc, then choosing to use the existing `tpidr_el0` convention
+would be friction-free alternative.
+
+It's not possible for an APE runtime that targets the full range of OSes
+to use the `tpidr_el0` register for TLS because Apple won't allow it. On
+MacOS ARM64 systems, this register can only be used by a runtime to
+implement the `sched_getcpu()` system call. It's reserved by MacOS.
+
+#### x86-64
+
+Here's the TLS memory layout on x86_64:
+
+```
+                          __get_tls()
+                              │
+                             %fs OpenBSD/NetBSD
+           _Thread_local      │
+    ┌───┬──────────┬──────────┼───┐
+    │pad│  .tdata  │  .tbss   │tib│
+    └───┴──────────┴──────────┼───┘
+                              │
+   Linux/FreeBSD/Windows/Mac %gs
+```
+
+Quite possibly the greatest challenge in Actually Portable Executable
+working, has been overcoming the incompatibilities between OSes in how
+thread-local storage works on x86-64. The AMD64 architecture defines two
+special segment registers. Every OS uses one of these segment registers
+to implement TLS support. However not all OSes agree on which register
+to use. Some OSes grant userspace the power to define either of these
+registers to hold any value that is desired. Some OSes only effectively
+allow a single one of them to be changed. Lastly, some OSes, e.g.
+Windows, claim ownership of the memory layout these registers point
+towards too.
+
+Here's a breakdown on how much power is granted to userspace runtimes by
+each OS when it comes to changing amd64 segment registers.
+
+|         | %fs          | %gs          |
+|---------|--------------|--------------|
+| Linux   | unrestricted | unrestricted |
+| MacOS   | inaccessible | unrestricted |
+| Windows | inaccessible | restricted   |
+| FreeBSD | unrestricted | unrestricted |
+| NetBSD  | unrestricted | broken       |
+| OpenBSD | unrestricted | inaccessible |
+
+Therefore, regardless of which register one we choose, some OSes are
+going to be incompatible.
+
+APE binaries are always built with a Linux compiler. So another issue
+arises in the fact that our Linux-flavored GCC and Clang toolchains
+(which are used to produce cross-OS binaries) are also only capable of
+producing TLS instructions that use the %fs convention.
+
+To solve these challenges, the `cosmocc` compiler will rewrite binary
+objects after they've been compiled by GCC, so that the `%gs` register
+is used, rather than `%fs`. Morphing x86-64 binaries after they've been
+compiled is normally difficult, due to the complexity of the machine
+instruction language. However GCC provides `-mno-tls-direct-seg-refs`
+which greatly reduces the complexity of this task. This flag forgoes
+some optimizations to make the generated code simpler. Rather than doing
+clever arithmetic with `%fs` prefixes, the compiler will always generate
+the thread information block address load as a separate instruction.
+
+```c
+// Change AMD code to use %gs:0x30 instead of %fs:0
+// We assume -mno-tls-direct-seg-refs has been used
+static void ChangeTlsFsToGs(unsigned char *p, size_t n) {
+  unsigned char *e = p + n - 9;
+  while (p <= e) {
+    // we're checking for the following expression:
+    //   0144 == p[0] &&           // %fs
+    //   0110 == (p[1] & 0373) &&  // rex.w (and ignore rex.r)
+    //   (0213 == p[2] ||          // mov reg/mem → reg (word-sized)
+    //   0003 == p[2]) &&          // add reg/mem → reg (word-sized)
+    //   0004 == (p[3] & 0307) &&  // mod/rm (4,reg,0) means sib → reg
+    //   0045 == p[4] &&           // sib (5,4,0) → (rbp,rsp,0) → disp32
+    //   0000 == p[5] &&           // displacement (von Neumann endian)
+    //   0000 == p[6] &&           // displacement
+    //   0000 == p[7] &&           // displacement
+    //   0000 == p[8]              // displacement
+    uint64_t w = READ64LE(p) & READ64LE("\377\373\377\307\377\377\377\377");
+    if ((w == READ64LE("\144\110\213\004\045\000\000\000") ||
+         w == READ64LE("\144\110\003\004\045\000\000\000")) &&
+        !p[8]) {
+      p[0] = 0145;  // change %fs to %gs
+      p[5] = 0x30;  // change 0 to 0x30
+      p += 9;
+    } else {
+      ++p;
+    }
+  }
+}
+```
+
+By favoring `%gs` we've now ensured friction-free compatibility for the
+APE runtime on MacOS, Linux, and FreeBSD which are all able to conform
+easily to this convention. However additional work needs to be done at
+runtime when an APE program is started on Windows, OpenBSD, and NetBSD.
+On these platforms, all executable pages must be faulted and morphed to
+fixup the TLS instructions.
+
+On OpenBSD and NetBSD, this is as simple as undoing the example
+operation above. Earlier at compile-time we turned `%fs` into `%gs`.
+Now, at runtime, `%gs` must be turned back into `%fs`. Since the
+executable is morphing itself, this is easier said than done.
+
+OpenBSD for example enforces a `W^X` invariant. Code that's executing
+can't modify itself at the same time. The way Cosmopolitan solves this
+is by defining a special part of the binary called `.text.privileged`.
+This section is aligned to page boundaries. A GNU ld linker script is
+used to ensure that code which morphs code is placed into this section,
+through the use of a header-defined cosmo-specific keyword `privileged`.
+Additionally, the `fixupobj` program is used by the Cosmo build system
+to ensure that compiled objects don't contain privileged functions that
+call non-privileged functions. Needless to say, `mprotect()` needs to be
+a privileged function, so that it can be used to disable the execute bit
+on all other parts of the executable except for the privileged section,
+thereby making it writable. Once this has been done, code can change.
+
+On Windows the displacement bytes of the TLS instruction are changed to
+use the `%gs:0x1480+i*8` ABI where `i` is a number assigned by the WIN32
+`TlsAlloc()` API. This avoids the need to call `TlsGetValue()` which is
+implemented this exact same way under the hood. Even though 0x1480 isn't
+explicitly documented by MSDN, this ABI is believed to be stable because
+MSVC generates binaries that use this offset directly. The only caveat
+is that `TlsAlloc()` must be called as early in the runtime init as
+possible, to ensure an index less than 64 is returned.
+
+### Thread Information Block (TIB)
+
+The Actually Portable Executable Thread Information Block (TIB) is
+defined by this version of the specification as follows:
+
+- The 64-bit TIB self-pointer is stored at offset 0x00.
+- The 64-bit TIB self-pointer is also stored at offset 0x30.
+- The 32-bit `errno` value is stored at offset 0x3c.
+
+All other parts of the thread information block should be considered
+unspecified and therefore reserved for future specifications.
+
+The APE thread information block is aligned on a 64-byte boundary.
+
+Cosmopolitan Libc v3.5.8 (c. 2024-07-21) currently implements a thread
+information block that's 512 bytes in size.
+
+### Foreign Function Calls
+
+Even though APE programs always use the System V ABI, there arises the
+occasional need to interface with foreign functions, e.g. WIN32. The
+`__attribute__((__ms_abi__))` annotation introduced by GCC v6 is used
+for this purpose.
+
+The ability to change a function's ABI on a case-by-case basis is
+surprisingly enough supported by GCC, Clang, NVCC, and even the AMD HIP
+compilers for both UNIX systems and Windows. All of these compilers
+support both the System V ABI and the Microsoft x64 ABI.
+
+APE binaries will actually favor the Microsoft ABI even when running on
+UNIX OSes for certain dlopen() use-cases. For example, if we control the
+code to a CUDA module, which we compile on each OS separately from our
+main APE binary, then any function that's inside the APE binary whose
+pointer may be passed into a foreign module SHOULD be compiled to use
+the Microsoft ABI. This is because in practice the OS-specific module
+may need to be compiled by MSVC, where MS ABI is the *only* ABI, which
+forces our UNIX programs to partially conform. Thankfully, all UNIX
+compilers support doing it on a case-by-case basis.
+
+### Char Signedness
+
+Actually Portable Executable defines `char` as signed.
+
+Therefore conformant APE software MUST use `-fsigned-char` when building
+code for aarch64, as well as any other architecture that (unlike x86-64)
+would otherwise define `char` as being `unsigned char` by default.
+
+This decision was one of the cases where it made sense to offer a more
+consistent runtime experience for fat multi-arch binaries. However you
+SHOULD still write code to assume `char` can go either way. But if all
+you care about is using APE, then you CAN assume `char` is signed.
+
+### Long Double
+
+On AMD64 platforms, APE binaries define `long double` as 80-bit.
+
+On ARM64 platforms, APE binaries define `long double` as 128-bit.
+
+We accept inconsistency in this case, because hardware acceleration is
+far more valuable than stylistic consistency in the case of mathematics.
+
+One challenge arises on AMD64 for supporting `long double` across OSes.
+Unlike UNIX systems, the Windows Executive on x86-64 initializes the x87
+FPU to have double (64-bit) precision rather than 80-bit. That's because
+code compiled by MSVC treats `long double` as though it were `double` to
+prefer always using the more modern SSE instructions. However System V
+requires genuine 80-bit `long double` support on AMD64.
+
+Therefore, if an APE program detects that it's been started on a Windows
+x86-64 system, then it SHOULD use the following assembly to initialize
+the x87 FPU in System V ABI mode.
+
+```asm
+	fldcw	1f(%rip)
+	.rodata
+	.balign	2
+//	8087 FPU Control Word
+//	 IM: Invalid Operation ───────────────┐
+//	 DM: Denormal Operand ───────────────┐│
+//	 ZM: Zero Divide ───────────────────┐││
+//	 OM: Overflow ─────────────────────┐│││
+//	 UM: Underflow ───────────────────┐││││
+//	 PM: Precision ──────────────────┐│││││
+//	 PC: Precision Control ───────┐  ││││││
+//	  {float,∅,double,long double}│  ││││││
+//	 RC: Rounding Control ──────┐ │  ││││││
+//	  {even, →-∞, →+∞, →0}      │┌┤  ││││││
+//	                           ┌┤││  ││││││
+//	                          d││││rr││││││
+1:	.short	0b00000000000000000001101111111
+	.previous
+```
+
+## Executable File Alignment
+
+Actually Portable Executable is a statically-linked flat executable file
+format that is, as a thing in itself, agnostic to file alignments. For
+example, the shell script payload at the beginning of the file and its
+statements have no such requirements. Alignment requirements are however
+imposed by the executable formats that APE wraps.
+
+1. ELF requires that file offsets be congruent with virtual addresses
+   modulo the CPU page size. So when we add a shell script to the start
+   of an executable, we need to round up to the page size in order to
+   maintain ELF's invariant. Although no such roundup is required on the
+   program segments once the invariant is restored. ELF loaders will
+   happily map program headers from arbitrary file intervals (which may
+   overlap) onto arbitrarily virtual intervals (which don't need to be
+   contiguous). In order to do that, the loaders will generally use
+   UNIX's mmap() function which is more restrictive and only accepts
+   addresses and offsets that are page aligned. To make it possible to
+   map an unaligned ELF program header that could potentially start and
+   stop at any byte, ELF loaders round-out the intervals, which means
+   adjacent unrelated data might also get mapped, which may need to be
+   explicitly zero'd. Thanks to the cleverness of ELF, it's possible to
+   have an executable file be very tiny, without needing any alignment
+   bytes, and it'll be loaded into a properly aligned virtual space
+   where segments can be as sparse as we want them to be.
+
+2. PE doesn't care about congruence and instead defines two separate
+   kinds of alignment. First, PE requires that the layout of segment
+   memory inside the file be aligned on at minimum the classic 512 byte
+   MS-DOS page size. This means that, unlike ELF, some alignment padding
+   may need to be encoded into the file, making it slightly larger. Next
+   PE imposes an alignment restriction on segments once they've been
+   mapped into the virtual address space, which must be rounded to the
+   system page size. Like ELF, PE segments need to be properly ordered
+   but they're allowed to drift apart once mapped in a non-contiguous
+   sparsely mapped way. When inserting shell script content at the start
+   of a PE file, the most problematic thing is the need to round up to
+   the 64kb system granularity, which results in a lot of needless bytes
+   of padding being inserted by a naive second-pass linker.
+
+3. Apple's Mach-O format is the strictest of them all. While both ELF
+   and PE are defined in such a way that invites great creativity, XNU
+   will simply refuse to an executable that does anything creative with
+   alignment. All loaded segments need to both start and end on a page
+   aligned address. XNU also wants segments to be contiguous similar to
+   portable executable, except it applies to both the file and virtual
+   spaces, which must follow the same structure.
+
+Actually Portable Executables must conform to the strictest requirements
+demanded by the support vector. Therefore an APE binary that has headers
+for all three of the above executable formats MUST conform to the Apple
+way of doing things. GNU ld linker scripts aren't very good at producing
+ELF binaries that rigidly conform to this simple naive layout. There are
+so many ways things can go wrong, where third party code might slip its
+own custom section name in-between the linker script sections that are
+explicitly defined, thereby causing ELF's powerful features to manifest
+and the resulting content overlapping. The best `ld` flag that helps is
+`--orphan-handling=error` which can help with explaining such mysteries.
+
+While Cosmopolitan was originally defined to just use stock GNU tools,
+this proved intractable over time, and the project has been evolving in
+the direction of building its own. Inventing the `apelink` program was
+what enabled the project to achieve multi-architecture binaries whereas
+previously it was only possible to do multi-OS binaries. In the future,
+our hope is that a fast power linker like Mold can be adapted to produce
+fat APE binaries directly from object files in one pass.
+
+## Position Independent Code
+
+APE doesn't currently support position independent executable formats.
+This is because APE was originally written for the GNU linker, where PIC
+and PIE were after-thoughts and never fully incorporated with the older
+more powerful linker script techniques upon which APE relies. Future
+iterations of this specification are intended to converge on modern
+standards, as our tooling becomes developed enough to support it.
+
+However this only applies to the wrapped executable formats themselves.
+While our convention to date has been to always load ELF programs at the
+4mb mark, this is not guaranteed across OSes and architectures. Programs
+should have no expectations that a program will be loaded to any given
+address. For example, Cosmo currently implements APE on AARCH64 as
+loading executables to a starting address of 0x000800000000. This
+address occupies a sweet spot of requirements.
+
+## Address Space
+
+In order to create a single binary that supports as many platforms as
+possible without needing to be recompiled, there's a very narrow range
+of addresses that can be used. That range is somewhere between 32 bits
+and 39 bits.
+
+- Embedded devices that claim to be 64-bit will oftentimes only support
+  a virtual address space that's 39 bits in size.
+
+- We can't load executable images on AARCH64 beneath 0x100000000 (4gb)
+  because Apple forbids doing that, possibly in an effort to enforce a
+  best practice for spotting 32-bit to 64-bit transition bugs. Please
+  note that this restriction only applies to Apple ARM64 systems. The
+  x86-64 version of XNU will happily load APE binaries to 0x00400000.
+
+- The AMD64 architecture on desktops and servers can usually be counted
+  upon to provide a 47-bit address space. The Linux Kernel for instance
+  grants each userspace program full dominion over addresses 0x00200000
+  through 0x00007fffffffffff provided the hardware supports this. On
+  modern workstations supporting Intel and AMD's new PML5T feature which
+  virtualizes memory using a radix trie that's five layers deep, Linux
+  is able to offer userspace its choice of fixed addresses from
+  0x00200000 through 0x00ffffffffffffff. The only exception to this rule
+  we've encountered so far is that Windows 7 and Windows Vista behaved
+  similar to embedded devices in reducing the number of va bits.
+
+## Page Size
+
+APE software MUST be page size agnostic. For many years the industry had
+converged on a strong consensus of having a page size that's 4096 bytes.
+However this convention was never guaranteed. New computers have become
+extremely popular, such as Apple Silicon, that use a 16kb page size.
+
+By convention, Cosmopolitan Libc currently generates ELF headers for
+x86-64 that are strictly aligned on a 4096-byte page size. On ARM64
+Cosmopolitan is currently implemented to always generate ELF headers
+aligned on a 16kb page size.
+
+In addition to being page size agnostic, APE software that cares about
+working correctly on Windows needs to be aware of the concept of
+allocation granularity. While the page size on Windows is generally 4kb
+in size, memory mappings can only be created on addresses that aligned
+to the system allocation granularity, which is generally 64kb. If you
+use a function like mmap() with Cosmopolitan Libc, then the `addr` and
+`offset` parameters need to be aligned to `sysconf(_SC_GRANSIZE)` or
+else your software won't work on Windows. Windows has other limitations
+too, such as lacking the ability to carve or punch holes in mappings.
@@ -18,7 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/dce.h"
 #include "ape/ape.h"
-#include "libc/macros.internal.h"
+#include "libc/macros.h"

 #ifdef __aarch64__

@@ -16,7 +16,7 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/macros.internal.h"
+#include "libc/macros.h"

 //	Invokes system call.
 //
@@ -14,7 +14,6 @@ ENABLE_FTRACE = 1
 CONFIG_OFLAGS ?= -g -ggdb
 CONFIG_CCFLAGS += -O2 $(BACKTRACES)
 CONFIG_CPPFLAGS += -DSYSDEBUG
-TARGET_ARCH ?= -msse3
 endif
 ifeq ($(MODE), x86_64)
 ENABLE_FTRACE = 1
@@ -64,7 +63,6 @@ ENABLE_FTRACE = 1
 CONFIG_CCFLAGS += $(BACKTRACES) -O
 CONFIG_CPPFLAGS += -DSYSDEBUG -DDWARFLESS
 CONFIG_LDFLAGS += -S
-TARGET_ARCH ?= -msse3
 endif

 # Optimized Mode
@@ -84,7 +82,7 @@ ENABLE_FTRACE = 1
 CONFIG_OFLAGS ?= -g -ggdb
 CONFIG_CPPFLAGS += -DNDEBUG -DSYSDEBUG
 CONFIG_CCFLAGS += $(BACKTRACES) -O3 -fmerge-all-constants
-TARGET_ARCH ?= -march=native
+CONFIG_TARGET_ARCH ?= -march=native
 endif

 # Optimized Linux Mode
@@ -102,7 +100,20 @@ CONFIG_OFLAGS ?= -g -ggdb
 CONFIG_CPPFLAGS += -DNDEBUG -DSYSDEBUG -DSUPPORT_VECTOR=1
 CONFIG_CCFLAGS += -O3 -fmerge-all-constants
 CONFIG_COPTS += -mred-zone
-TARGET_ARCH ?= -march=native
+CONFIG_TARGET_ARCH ?= -march=native
+endif
+ifeq ($(MODE), x86_64-optlinux)
+CONFIG_OFLAGS ?= -g -ggdb
+CONFIG_CPPFLAGS += -DNDEBUG -DSYSDEBUG -DSUPPORT_VECTOR=1
+CONFIG_CCFLAGS += -O3 -fmerge-all-constants
+CONFIG_COPTS += -mred-zone
+CONFIG_TARGET_ARCH ?= -march=native
+endif
+ifeq ($(MODE), aarch64-optlinux)
+CONFIG_OFLAGS ?= -g -ggdb
+CONFIG_CPPFLAGS += -DNDEBUG -DSYSDEBUG -DSUPPORT_VECTOR=1
+CONFIG_CCFLAGS += -O3 -fmerge-all-constants
+CONFIG_COPTS += -mred-zone
 endif

 # Release Mode
@@ -123,36 +134,13 @@ endif
 ifeq ($(MODE), rel)
 CONFIG_CPPFLAGS += -DNDEBUG -DDWARFLESS
 CONFIG_CCFLAGS += $(BACKTRACES) -O2
-TARGET_ARCH ?= -msse3
 PYFLAGS += -O1
 endif

-# Asan Mode
-#
-# Safer binaries good for backend production serving.
-#
-#   - `make MODE=asan`
-#   - Memory safety
-#   - Production worthy
-#   - Backtraces
-#   - Debuggability
-#   - Larger binaries
-#
-ifeq ($(MODE), asan)
-ENABLE_FTRACE = 1
-CONFIG_OFLAGS ?= -g -ggdb
-CONFIG_CPPFLAGS += -D__SANITIZE_ADDRESS__
-CONFIG_CCFLAGS += $(BACKTRACES) -O2 -DSYSDEBUG
-CONFIG_COPTS += -fsanitize=address
-TARGET_ARCH ?= -msse3
-QUOTA ?= -C64 -L300
-endif
-
 # Debug Mode
 #
 #   - `make MODE=dbg`
 #   - Backtraces
-#   - Enables asan
 #   - Enables ubsan
 #   - Stack canaries
 #   - No optimization
@@ -161,18 +149,32 @@ endif
 ifeq ($(MODE), dbg)
 ENABLE_FTRACE = 1
 CONFIG_OFLAGS ?= -g -ggdb
-CONFIG_CPPFLAGS += -DMODE_DBG -D__SANITIZE_ADDRESS__ -D__SANITIZE_UNDEFINED__
-CONFIG_CCFLAGS += $(BACKTRACES) -DSYSDEBUG -O0 -fno-inline
-CONFIG_COPTS += -fsanitize=address -fsanitize=undefined
-TARGET_ARCH ?= -msse3
+OVERRIDE_CFLAGS += -O0
+OVERRIDE_CXXFLAGS += -O0
+CONFIG_CPPFLAGS += -DMODE_DBG -D__SANITIZE_UNDEFINED__ -Wno-unused-variable -Wno-unused-but-set-variable
+CONFIG_CCFLAGS += $(BACKTRACES) -DSYSDEBUG
+CONFIG_COPTS += -fsanitize=undefined
+OVERRIDE_CCFLAGS += -fno-pie
+QUOTA ?= -C64 -L300
+endif
+ifeq ($(MODE), x86_64-dbg)
+ENABLE_FTRACE = 1
+CONFIG_OFLAGS ?= -g -ggdb
+OVERRIDE_CFLAGS += -O0
+OVERRIDE_CXXFLAGS += -O0
+CONFIG_CPPFLAGS += -DMODE_DBG -D__SANITIZE_UNDEFINED__ -Wno-unused-variable -Wno-unused-but-set-variable
+CONFIG_CCFLAGS += $(BACKTRACES) -DSYSDEBUG
+CONFIG_COPTS += -fsanitize=undefined
 OVERRIDE_CCFLAGS += -fno-pie
 QUOTA ?= -C64 -L300
 endif
 ifeq ($(MODE), aarch64-dbg)
 ENABLE_FTRACE = 1
 CONFIG_OFLAGS ?= -g -ggdb
-CONFIG_CPPFLAGS += -DMODE_DBG -D__SANITIZE_UNDEFINED__
-CONFIG_CCFLAGS += $(BACKTRACES) -DSYSDEBUG -O0 -fno-inline -fdce
+OVERRIDE_CFLAGS += -O0 -fdce
+OVERRIDE_CXXFLAGS += -O0 -fdce
+CONFIG_CPPFLAGS += -DMODE_DBG -D__SANITIZE_UNDEFINED__ -Wno-unused-variable -Wno-unused-but-set-variable
+CONFIG_CCFLAGS += $(BACKTRACES) -DSYSDEBUG
 CONFIG_COPTS += -fsanitize=undefined
 QUOTA ?= -C64 -L300
 endif
@@ -192,7 +194,6 @@ ENABLE_FTRACE = 1
 CONFIG_OFLAGS ?= -g -ggdb
 CONFIG_CCFLAGS += $(BACKTRACES) -O2
 CONFIG_CPPFLAGS += -DSYSDEBUG -DSUPPORT_VECTOR=121
-TARGET_ARCH ?= -msse3
 endif

 # Tiny Mode
@@ -222,8 +223,6 @@ CONFIG_CCFLAGS +=			\
 	-momit-leaf-frame-pointer	\
 	-foptimize-sibling-calls	\
 	-DDWARFLESS
-TARGET_ARCH ?=				\
-	-msse3
 PYFLAGS +=				\
 	-O2				\
 	-B
@@ -243,8 +242,6 @@ CONFIG_CCFLAGS +=			\
 	-momit-leaf-frame-pointer	\
 	-foptimize-sibling-calls	\
 	-DDWARFLESS
-TARGET_ARCH ?=				\
-	-msse3
 PYFLAGS +=				\
 	-O2				\
 	-B
@@ -296,8 +293,6 @@ CONFIG_CCFLAGS +=			\
 	-fno-align-jumps		\
 	-fno-align-labels		\
 	-fno-align-loops
-TARGET_ARCH ?=				\
-	-msse3
 endif

 # Linux+BSD Tiny Mode
@@ -327,8 +322,6 @@ CONFIG_CCFLAGS +=		\
 	-fno-align-jumps	\
 	-fno-align-labels	\
 	-fno-align-loops
-TARGET_ARCH ?=			\
-	-msse3
 endif

 # Unix Tiny Mode
@@ -357,8 +350,6 @@ CONFIG_CCFLAGS +=		\
 	-fno-align-jumps	\
 	-fno-align-labels	\
 	-fno-align-loops
-TARGET_ARCH ?=			\
-	-msse3
 endif

 # Tiny Metallic Unix Mode
@@ -387,8 +378,6 @@ CONFIG_CCFLAGS +=		\
 	-fno-align-jumps	\
 	-fno-align-labels	\
 	-fno-align-loops
-TARGET_ARCH ?=			\
-	-msse3
 endif

 # no x87 instructions mode
@@ -410,7 +399,6 @@ ENABLE_FTRACE = 1
 CONFIG_COPTS += -mlong-double-64
 CONFIG_CCFLAGS += $(BACKTRACES) -O2
 CONFIG_CPPFLAGS += -DSYSDEBUG -DNOX87
-TARGET_ARCH ?= -msse3
 endif

 # LLVM Mode
@@ -423,7 +411,6 @@ endif
 #
 ifeq ($(MODE), llvm)
 .STRICT = 0
-TARGET_ARCH ?= -msse3
 CONFIG_CCFLAGS += $(BACKTRACES) -DSYSDEBUG -O2
 AS = clang
 CC = clang
@@ -466,7 +453,6 @@ ifeq ($(MODE), ansi)
 CONFIG_CFLAGS += -std=c11
 #CONFIG_CPPFLAGS += -ansi
 CONFIG_CXXFLAGS += -std=c++11
-TARGET_ARCH ?= -msse3
 endif

 ifneq ($(ENABLE_FTRACE),)
@@ -524,3 +510,5 @@ ifeq ($(ARCH), aarch64)
 CONFIG_CCFLAGS += -fpatchable-function-entry=7,6
 endif
 endif
+
+TARGET_ARCH ?= $(CONFIG_TARGET_ARCH)
@@ -64,9 +64,6 @@ BACKTRACES =								\
 	-fno-optimize-sibling-calls					\
 	-mno-omit-leaf-frame-pointer

-SANITIZER =								\
-	-fsanitize=address
-
 NO_MAGIC =								\
 	-ffreestanding							\
 	-fno-stack-protector						\
@@ -95,10 +92,7 @@ DEFAULT_COPTS ?=							\
 	-fno-gnu-unique							\
 	-fstrict-aliasing						\
 	-fstrict-overflow						\
-	-fno-semantic-interposition					\
-	-fno-dwarf2-cfi-asm						\
-	-fno-unwind-tables						\
-	-fno-asynchronous-unwind-tables
+	-fno-semantic-interposition

 ifeq ($(ARCH), x86_64)
 # Microsoft says "[a]ny memory below the stack beyond the red zone
@@ -118,14 +112,10 @@ ifeq ($(ARCH), aarch64)
 # - Cosmopolitan Libc uses x28 for thread-local storage because Apple
 #   forbids us from using tpidr_el0 too.
 #
-# - Cosmopolitan currently lacks an implementation of the runtime
-#   libraries needed by the -moutline-atomics flag
-#
 DEFAULT_COPTS +=							\
 	-ffixed-x18							\
 	-ffixed-x28							\
-	-fsigned-char							\
-	-mno-outline-atomics
+	-fsigned-char
 endif

 MATHEMATICAL =								\
@@ -142,12 +132,10 @@ DEFAULT_CPPFLAGS +=							\
 	-isystem libc/isystem

 DEFAULT_CFLAGS =							\
-	-std=gnu2x
+	-std=gnu23

 DEFAULT_CXXFLAGS =							\
-	-std=gnu++20							\
-	-fno-rtti							\
-	-fno-exceptions							\
+	-std=gnu++23							\
 	-fuse-cxa-atexit						\
 	-Wno-int-in-bool-context					\
 	-Wno-narrowing							\
@@ -6,14 +6,14 @@ if [ -n "$OBJDUMP" ]; then
 fi

 find_objdump() {
-  if [ -x .cosmocc/3.3.5/bin/$1-linux-cosmo-objdump ]; then
-    OBJDUMP=.cosmocc/3.3.5/bin/$1-linux-cosmo-objdump
-  elif [ -x .cosmocc/3.3.5/bin/$1-linux-musl-objdump ]; then
-    OBJDUMP=.cosmocc/3.3.5/bin/$1-linux-musl-objdump
-  elif [ -x "$COSMO/.cosmocc/3.3.5/bin/$1-linux-cosmo-objdump" ]; then
-    OBJDUMP="$COSMO/.cosmocc/3.3.5/bin/$1-linux-cosmo-objdump"
-  elif [ -x "$COSMO/.cosmocc/3.3.5/bin/$1-linux-musl-objdump" ]; then
-    OBJDUMP="$COSMO/.cosmocc/3.3.5/bin/$1-linux-musl-objdump"
+  if [ -x .cosmocc/3.9.2/bin/$1-linux-cosmo-objdump ]; then
+    OBJDUMP=.cosmocc/3.9.2/bin/$1-linux-cosmo-objdump
+  elif [ -x .cosmocc/3.9.2/bin/$1-linux-musl-objdump ]; then
+    OBJDUMP=.cosmocc/3.9.2/bin/$1-linux-musl-objdump
+  elif [ -x "$COSMO/.cosmocc/3.9.2/bin/$1-linux-cosmo-objdump" ]; then
+    OBJDUMP="$COSMO/.cosmocc/3.9.2/bin/$1-linux-cosmo-objdump"
+  elif [ -x "$COSMO/.cosmocc/3.9.2/bin/$1-linux-musl-objdump" ]; then
+    OBJDUMP="$COSMO/.cosmocc/3.9.2/bin/$1-linux-musl-objdump"
  else
    echo "error: toolchain not found (try running 'cosmocc --update' or 'make' in the cosmo monorepo)" >&2
    exit 1
@@ -4,5 +4,5 @@ UNAMES=$(uname -s)
 if [ x"$UNAMES" = x"Darwin" ] && [ x"$UNAMEM" = x"arm64" ]; then
  exec ape "$@"
 else
-  exec "$@"
+  exec rusage "$@"
 fi
@@ -31,7 +31,7 @@ if [ ! -f /proc/sys/fs/binfmt_misc/status ]; then
  exit 0
 fi

-if ! build/bootstrap/echo.com -n; then
+if ! build/bootstrap/echo -n; then
  cat <<'EOF' >&2

 ERROR
@@ -18,7 +18,13 @@ CTL_A_CHECKS =						\
 CTL_A_DIRECTDEPS =					\
 	LIBC_INTRIN					\
 	LIBC_MEM					\
+	LIBC_NEXGEN32E					\
+	LIBC_STDIO					\
 	LIBC_STR					\
+	THIRD_PARTY_DOUBLECONVERSION			\
+	THIRD_PARTY_GDTOA				\
+	THIRD_PARTY_LIBCXXABI				\
+	THIRD_PARTY_LIBUNWIND				\

 CTL_A_DEPS := $(call uniq,$(foreach x,$(CTL_A_DIRECTDEPS),$($(x))))

@@ -36,6 +42,7 @@ $(CTL_A_OBJS): private					\
 			-Walloca-larger-than=4096	\
 			-ffunction-sections		\
 			-fdata-sections			\
+			-fexceptions			\

 CTL_LIBS = $(foreach x,$(CTL_ARTIFACTS),$($(x)))
 CTL_SRCS = $(foreach x,$(CTL_ARTIFACTS),$($(x)_SRCS))
@@ -12,7 +12,7 @@ This package provides an STL alternative that's designed to:

 This code is experimental and mostly for Justine to save herself from
 the STL trainwreck. That doesn't mean cosmocc users aren't welcome to
-use tihs too. You shouldn't expect the design to not change later on.
+use this too. You shouldn't expect the design to not change later on.

 ## Rationale

@@ -0,0 +1,28 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ACCUMULATE_H_
+#define CTL_ACCUMULATE_H_
+
+namespace ctl {
+
+template<class InputIt, class T>
+constexpr T
+accumulate(InputIt first, InputIt last, T init)
+{
+    for (; first != last; ++first)
+        init = init + *first;
+    return init;
+}
+
+template<class InputIt, class T, class BinaryOperation>
+constexpr T
+accumulate(InputIt first, InputIt last, T init, BinaryOperation op)
+{
+    for (; first != last; ++first)
+        init = op(init, *first);
+    return init;
+}
+
+} // namespace ctl
+
+#endif // CTL_ACCUMULATE_H_
@@ -0,0 +1,55 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ADD_LVALUE_REFERENCE_H_
+#define CTL_ADD_LVALUE_REFERENCE_H_
+
+namespace ctl {
+
+template<typename T>
+struct add_lvalue_reference
+{
+    typedef T& type;
+};
+
+template<typename T>
+struct add_lvalue_reference<T&>
+{
+    typedef T& type;
+};
+
+template<typename T>
+struct add_lvalue_reference<T&&>
+{
+    typedef T& type;
+};
+
+template<>
+struct add_lvalue_reference<void>
+{
+    typedef void type;
+};
+
+template<>
+struct add_lvalue_reference<const void>
+{
+    typedef const void type;
+};
+
+template<>
+struct add_lvalue_reference<volatile void>
+{
+    typedef volatile void type;
+};
+
+template<>
+struct add_lvalue_reference<const volatile void>
+{
+    typedef const volatile void type;
+};
+
+template<typename T>
+using add_lvalue_reference_t = typename add_lvalue_reference<T>::type;
+
+} // namespace ctl
+
+#endif // CTL_ADD_LVALUE_REFERENCE_H_
@@ -0,0 +1,43 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ADD_POINTER_H_
+#define CTL_ADD_POINTER_H_
+#include "remove_reference.h"
+
+namespace ctl {
+
+// Primary template
+template<typename T>
+struct add_pointer
+{
+    typedef typename remove_reference<T>::type* type;
+};
+
+// Specialization for functions
+template<typename R, typename... Args>
+struct add_pointer<R(Args...)>
+{
+    typedef R (*type)(Args...);
+};
+
+// Specialization for function references
+template<typename R, typename... Args>
+struct add_pointer<R (&)(Args...)>
+{
+    typedef R (*type)(Args...);
+};
+
+// Specialization for rvalue references to functions
+template<typename R, typename... Args>
+struct add_pointer<R (&&)(Args...)>
+{
+    typedef R (*type)(Args...);
+};
+
+// Helper alias template (C++14 and later)
+template<typename T>
+using add_pointer_t = typename add_pointer<T>::type;
+
+} // namespace ctl
+
+#endif // CTL_ADD_POINTER_H_
@@ -0,0 +1,29 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ADDRESSOF_H_
+#define CTL_ADDRESSOF_H_
+
+namespace ctl {
+
+template<typename T>
+T*
+addressof(T& arg) noexcept
+{
+    return reinterpret_cast<T*>(
+      &const_cast<char&>(reinterpret_cast<const volatile char&>(arg)));
+}
+
+template<typename R, typename... Args>
+R (*addressof(R (*&arg)(Args...)) noexcept)
+(Args...)
+{
+    return arg;
+}
+
+template<typename T>
+T*
+addressof(T&&) = delete;
+
+} // namespace ctl
+
+#endif // CTL_ADDRESSOF_H_
@@ -0,0 +1,24 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ADVANCE_H_
+#define CTL_ADVANCE_H_
+
+namespace ctl {
+
+template<class InputIt, class Distance>
+constexpr void
+advance(InputIt& it, Distance n)
+{
+    while (n > 0) {
+        --n;
+        ++it;
+    }
+    while (n < 0) {
+        ++n;
+        --it;
+    }
+}
+
+} // namespace ctl
+
+#endif // CTL_ADVANCE_H_
@@ -0,0 +1,20 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ALL_OF_H_
+#define CTL_ALL_OF_H_
+
+namespace ctl {
+
+template<class InputIt, class UnaryPredicate>
+constexpr bool
+all_of(InputIt first, InputIt last, UnaryPredicate p)
+{
+    for (; first != last; ++first)
+        if (!p(*first))
+            return false;
+    return true;
+}
+
+} // namespace ctl
+
+#endif // CTL_ALL_OF_H_
@@ -0,0 +1,94 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ALLOCATOR_H_
+#define CTL_ALLOCATOR_H_
+#include "bad_alloc.h"
+#include "integral_constant.h"
+#include "new.h"
+#include "utility.h"
+
+namespace ctl {
+
+template<typename T>
+class allocator
+{
+  public:
+    using value_type = T;
+    using size_type = size_t;
+    using difference_type = ptrdiff_t;
+    using propagate_on_container_move_assignment = ctl::true_type;
+    using is_always_equal = ctl::true_type;
+    using pointer = T*;
+    using const_pointer = const T*;
+    using reference = T&;
+    using const_reference = const T&;
+
+    constexpr allocator() noexcept = default;
+
+    constexpr allocator(const allocator&) noexcept = default;
+
+    template<class U>
+    constexpr allocator(const allocator<U>&) noexcept
+    {
+    }
+
+    constexpr ~allocator() = default;
+
+    [[nodiscard]] T* allocate(size_type n)
+    {
+        if (n > __SIZE_MAX__ / sizeof(T))
+            throw ctl::bad_alloc();
+        if (auto p = static_cast<T*>(::operator new(
+              n * sizeof(T), ctl::align_val_t(alignof(T)), ctl::nothrow)))
+            return p;
+        throw ctl::bad_alloc();
+    }
+
+    void deallocate(T* p, size_type n) noexcept
+    {
+        ::operator delete(p, n * sizeof(T), ctl::align_val_t(alignof(T)));
+    }
+
+    template<typename U, typename... Args>
+    void construct(U* p, Args&&... args)
+    {
+        ::new (static_cast<void*>(p)) U(ctl::forward<Args>(args)...);
+    }
+
+    template<typename U>
+    void destroy(U* p)
+    {
+        p->~U();
+    }
+
+    size_type max_size() const noexcept
+    {
+        return __SIZE_MAX__ / sizeof(T);
+    }
+
+    allocator& operator=(const allocator&) = default;
+
+    template<typename U>
+    struct rebind
+    {
+        using other = allocator<U>;
+    };
+};
+
+template<class T, class U>
+bool
+operator==(const allocator<T>&, const allocator<U>&) noexcept
+{
+    return true;
+}
+
+template<class T, class U>
+bool
+operator!=(const allocator<T>&, const allocator<U>&) noexcept
+{
+    return false;
+}
+
+} // namespace ctl
+
+#endif // CTL_ALLOCATOR_H_
@@ -0,0 +1,70 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ALLOCATOR_TRAITS_H_
+#define CTL_ALLOCATOR_TRAITS_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename Alloc>
+struct allocator_traits
+{
+    using allocator_type = Alloc;
+    using value_type = typename Alloc::value_type;
+    using pointer = typename Alloc::value_type*;
+    using const_pointer = const typename Alloc::value_type*;
+    using void_pointer = void*;
+    using const_void_pointer = const void*;
+    using difference_type = ptrdiff_t;
+    using size_type = size_t;
+
+    using propagate_on_container_copy_assignment = ctl::false_type;
+    using propagate_on_container_move_assignment = ctl::true_type;
+    using propagate_on_container_swap = ctl::false_type;
+    using is_always_equal = ctl::true_type;
+
+    template<typename T>
+    struct rebind_alloc
+    {
+        using other = typename Alloc::template rebind<T>::other;
+    };
+
+    template<typename T>
+    using rebind_traits = allocator_traits<typename rebind_alloc<T>::other>;
+
+    static pointer allocate(Alloc& a, size_type n)
+    {
+        return a.allocate(n);
+    }
+
+    static void deallocate(Alloc& a, pointer p, size_type n)
+    {
+        a.deallocate(p, n);
+    }
+
+    template<typename T, typename... Args>
+    static void construct(Alloc& a, T* p, Args&&... args)
+    {
+        ::new ((void*)p) T(static_cast<Args&&>(args)...);
+    }
+
+    template<typename T>
+    static void destroy(Alloc& a, T* p)
+    {
+        p->~T();
+    }
+
+    static size_type max_size(const Alloc& a) noexcept
+    {
+        return a.max_size();
+    }
+
+    static Alloc select_on_container_copy_construction(const Alloc& a)
+    {
+        return a;
+    }
+};
+
+} // namespace ctl
+
+#endif // CTL_ALLOCATOR_TRAITS_H_
@@ -0,0 +1,20 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ANY_OF_H_
+#define CTL_ANY_OF_H_
+
+namespace ctl {
+
+template<class InputIt, class UnaryPredicate>
+constexpr bool
+any_of(InputIt first, InputIt last, UnaryPredicate p)
+{
+    for (; first != last; ++first)
+        if (p(*first))
+            return true;
+    return false;
+}
+
+} // namespace ctl
+
+#endif // CTL_ANY_OF_H_
@@ -0,0 +1,248 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ARRAY_H_
+#define CTL_ARRAY_H_
+#include "initializer_list.h"
+#include "out_of_range.h"
+#include "reverse_iterator.h"
+
+namespace ctl {
+
+template<typename T, size_t N>
+struct array
+{
+    using value_type = T;
+    using size_type = size_t;
+    using difference_type = ptrdiff_t;
+    using reference = value_type&;
+    using const_reference = const value_type&;
+    using pointer = value_type*;
+    using const_pointer = const value_type*;
+    using iterator = value_type*;
+    using const_iterator = const value_type*;
+    using reverse_iterator = ctl::reverse_iterator<iterator>;
+    using const_reverse_iterator = ctl::reverse_iterator<const_iterator>;
+
+    T elems[N];
+
+    constexpr array() = default;
+
+    constexpr array(std::initializer_list<T> init)
+    {
+        auto it = init.begin();
+        for (size_t i = 0; i < N && it != init.end(); ++i, ++it)
+            elems[i] = *it;
+    }
+
+    constexpr reference at(size_type pos)
+    {
+        if (pos >= N)
+            throw ctl::out_of_range();
+        return elems[pos];
+    }
+
+    constexpr const_reference at(size_type pos) const
+    {
+        if (pos >= N)
+            throw ctl::out_of_range();
+        return elems[pos];
+    }
+
+    constexpr reference operator[](size_type pos)
+    {
+        if (pos >= N)
+            __builtin_trap();
+        return elems[pos];
+    }
+
+    constexpr const_reference operator[](size_type pos) const
+    {
+        if (pos >= N)
+            __builtin_trap();
+        return elems[pos];
+    }
+
+    constexpr reference front()
+    {
+        return elems[0];
+    }
+
+    constexpr const_reference front() const
+    {
+        return elems[0];
+    }
+
+    constexpr reference back()
+    {
+        return elems[N - 1];
+    }
+
+    constexpr const_reference back() const
+    {
+        return elems[N - 1];
+    }
+
+    constexpr T* data() noexcept
+    {
+        return elems;
+    }
+
+    constexpr const T* data() const noexcept
+    {
+        return elems;
+    }
+
+    constexpr iterator begin() noexcept
+    {
+        return elems;
+    }
+
+    constexpr const_iterator begin() const noexcept
+    {
+        return elems;
+    }
+
+    constexpr iterator end() noexcept
+    {
+        return elems + N;
+    }
+
+    constexpr const_iterator end() const noexcept
+    {
+        return elems + N;
+    }
+
+    constexpr reverse_iterator rbegin() noexcept
+    {
+        return reverse_iterator(end());
+    }
+
+    constexpr const_reverse_iterator rbegin() const noexcept
+    {
+        return const_reverse_iterator(end());
+    }
+
+    constexpr reverse_iterator rend() noexcept
+    {
+        return reverse_iterator(begin());
+    }
+
+    constexpr const_reverse_iterator rend() const noexcept
+    {
+        return const_reverse_iterator(begin());
+    }
+
+    constexpr const_iterator cbegin() const noexcept
+    {
+        return begin();
+    }
+
+    constexpr const_iterator cend() const noexcept
+    {
+        return end();
+    }
+
+    constexpr const_reverse_iterator crbegin() const noexcept
+    {
+        return rbegin();
+    }
+
+    constexpr const_reverse_iterator crend() const noexcept
+    {
+        return rend();
+    }
+
+    constexpr bool empty() const noexcept
+    {
+        return N == 0;
+    }
+
+    constexpr size_type size() const noexcept
+    {
+        return N;
+    }
+
+    constexpr size_type max_size() const noexcept
+    {
+        return N;
+    }
+
+    void fill(const T& value)
+    {
+        for (size_type i = 0; i < N; ++i) {
+            elems[i] = value;
+        }
+    }
+
+    void swap(array& other) noexcept
+    {
+        for (size_type i = 0; i < N; ++i) {
+            T temp = elems[i];
+            elems[i] = other.elems[i];
+            other.elems[i] = temp;
+        }
+    }
+};
+
+template<typename T, size_t N>
+bool
+operator==(const array<T, N>& lhs, const array<T, N>& rhs)
+{
+    for (size_t i = 0; i < N; ++i) {
+        if (!(lhs[i] == rhs[i]))
+            return false;
+    }
+    return true;
+}
+
+template<typename T, size_t N>
+bool
+operator!=(const array<T, N>& lhs, const array<T, N>& rhs)
+{
+    return !(lhs == rhs);
+}
+
+template<typename T, size_t N>
+bool
+operator<(const array<T, N>& lhs, const array<T, N>& rhs)
+{
+    for (size_t i = 0; i < N; ++i) {
+        if (lhs[i] < rhs[i])
+            return true;
+        if (rhs[i] < lhs[i])
+            return false;
+    }
+    return false;
+}
+
+template<typename T, size_t N>
+bool
+operator<=(const array<T, N>& lhs, const array<T, N>& rhs)
+{
+    return !(rhs < lhs);
+}
+
+template<typename T, size_t N>
+bool
+operator>(const array<T, N>& lhs, const array<T, N>& rhs)
+{
+    return rhs < lhs;
+}
+
+template<typename T, size_t N>
+bool
+operator>=(const array<T, N>& lhs, const array<T, N>& rhs)
+{
+    return !(lhs < rhs);
+}
+
+template<typename T, size_t N>
+void
+swap(array<T, N>& lhs, array<T, N>& rhs) noexcept
+{
+    lhs.swap(rhs);
+}
+
+} // namespace ctl
+
+#endif // CTL_ARRAY_H_
@@ -0,0 +1,64 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_BACK_INSERTER_H_
+#define CTL_BACK_INSERTER_H_
+#include "iterator.h"
+#include "utility.h"
+
+namespace ctl {
+
+template<class Container>
+class back_insert_iterator
+{
+  protected:
+    Container* container;
+
+  public:
+    using iterator_category = ctl::output_iterator_tag;
+    using value_type = void;
+    using difference_type = void;
+    using pointer = void;
+    using reference = void;
+
+    explicit back_insert_iterator(Container& c) : container(&c)
+    {
+    }
+
+    back_insert_iterator& operator=(const typename Container::value_type& value)
+    {
+        container->push_back(value);
+        return *this;
+    }
+
+    back_insert_iterator& operator=(typename Container::value_type&& value)
+    {
+        container->push_back(ctl::move(value));
+        return *this;
+    }
+
+    back_insert_iterator& operator*()
+    {
+        return *this;
+    }
+
+    back_insert_iterator& operator++()
+    {
+        return *this;
+    }
+
+    back_insert_iterator operator++(int)
+    {
+        return *this;
+    }
+};
+
+template<class Container>
+back_insert_iterator<Container>
+back_inserter(Container& c)
+{
+    return back_insert_iterator<Container>(c);
+}
+
+} // namespace ctl
+
+#endif // CTL_BACK_INSERTER_H_
@@ -0,0 +1,23 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_BAD_ALLOC_H_
+#define CTL_BAD_ALLOC_H_
+#include "exception.h"
+
+namespace ctl {
+
+class bad_alloc : public ctl::exception
+{
+  public:
+    bad_alloc() noexcept = default;
+    ~bad_alloc() override = default;
+
+    const char* what() const noexcept override
+    {
+        return "ctl::bad_alloc";
+    }
+};
+
+} // namespace ctl
+
+#endif // CTL_BAD_ALLOC_H_
@@ -0,0 +1,25 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_CONDITIONAL_H_
+#define CTL_CONDITIONAL_H_
+
+namespace ctl {
+
+template<bool B, class T, class F>
+struct conditional
+{
+    typedef T type;
+};
+
+template<class T, class F>
+struct conditional<false, T, F>
+{
+    typedef F type;
+};
+
+template<bool B, typename T, typename F>
+using conditional_t = typename conditional<B, T, F>::type;
+
+} // namespace ctl
+
+#endif // CTL_CONDITIONAL_H_
@@ -0,0 +1,22 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_COPY_H_
+#define CTL_COPY_H_
+
+namespace ctl {
+
+template<class InputIt, class OutputIt>
+OutputIt
+copy(InputIt first, InputIt last, OutputIt d_first)
+{
+    while (first != last) {
+        *d_first = *first;
+        ++d_first;
+        ++first;
+    }
+    return d_first;
+}
+
+} // namespace ctl
+
+#endif // CTL_COPY_H_
@@ -0,0 +1,36 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_DECAY_H_
+#define CTL_DECAY_H_
+#include "add_pointer.h"
+#include "conditional.h"
+#include "is_array.h"
+#include "is_function.h"
+#include "remove_cv.h"
+#include "remove_extent.h"
+#include "remove_reference.h"
+
+namespace ctl {
+
+template<typename T>
+struct decay
+{
+  private:
+    typedef typename ctl::remove_reference<T>::type U;
+
+  public:
+    typedef typename ctl::conditional<
+      ctl::is_array<U>::value,
+      typename ctl::remove_extent<U>::type*,
+      typename ctl::conditional<ctl::is_function<U>::value,
+                                typename ctl::add_pointer<U>::type,
+                                typename ctl::remove_cv<U>::type>::type>::type
+      type;
+};
+
+template<typename T>
+using decay_t = typename decay<T>::type;
+
+} // namespace ctl
+
+#endif // CTL_DECAY_H_
@@ -0,0 +1,44 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_DEFAULT_DELETE_H_
+#define CTL_DEFAULT_DELETE_H_
+#include "enable_if.h"
+#include "is_convertible.h"
+
+namespace ctl {
+
+template<typename T>
+struct default_delete
+{
+    constexpr default_delete() noexcept = default;
+    template<typename U,
+             typename = typename ctl::enable_if<
+               ctl::is_convertible<U*, T*>::value>::type>
+    constexpr default_delete(const default_delete<U>&) noexcept
+    {
+    }
+    constexpr void operator()(T* const p) const noexcept
+    {
+        delete p;
+    }
+};
+
+template<typename T>
+struct default_delete<T[]>
+{
+    constexpr default_delete() noexcept = default;
+    template<typename U,
+             typename = typename ctl::enable_if<
+               ctl::is_convertible<U (*)[], T (*)[]>::value>::type>
+    constexpr default_delete(const default_delete<U[]>&) noexcept
+    {
+    }
+    constexpr void operator()(T* const p) const noexcept
+    {
+        delete[] p;
+    }
+};
+
+} // namespace ctl
+
+#endif // CTL_DEFAULT_DELETE_H_
@@ -0,0 +1,39 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_DISTANCE_H_
+#define CTL_DISTANCE_H_
+#include "iterator.h"
+#include "iterator_traits.h"
+
+namespace ctl {
+
+template<class InputIter>
+constexpr typename ctl::iterator_traits<InputIter>::difference_type
+distance_impl(InputIter first, InputIter last, input_iterator_tag)
+{
+    typename ctl::iterator_traits<InputIter>::difference_type res(0);
+    for (; first != last; ++first)
+        ++res;
+    return res;
+}
+
+template<class RandIter>
+constexpr typename ctl::iterator_traits<RandIter>::difference_type
+distance_impl(RandIter first, RandIter last, random_access_iterator_tag)
+{
+    return last - first;
+}
+
+template<class InputIter>
+constexpr typename ctl::iterator_traits<InputIter>::difference_type
+distance(InputIter first, InputIter last)
+{
+    return distance_impl(
+      first,
+      last,
+      typename ctl::iterator_traits<InputIter>::iterator_category());
+}
+
+} // namespace ctl
+
+#endif // CTL_DISTANCE_H_
@@ -0,0 +1,35 @@
+// -*- mode:c++; indent-tabs-mode:nil; c-basic-offset:4; coding:utf-8 -*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+//
+// Copyright 2024 Justine Alexandra Roberts Tunney
+//
+// Permission to use, copy, modify, and/or distribute this software for
+// any purpose with or without fee is hereby granted, provided that the
+// above copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+// WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+// AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+// DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+// PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include "dubble.h"
+
+namespace ctl {
+
+const double_conversion::DoubleToStringConverter kDoubleToPrintfG(
+  double_conversion::DoubleToStringConverter::EMIT_POSITIVE_EXPONENT_SIGN |
+    double_conversion::DoubleToStringConverter::NO_TRAILING_ZERO,
+  "inf",
+  "nan",
+  'e',
+  -6,
+  10, // let 32-bit ints be represented without exponent
+  6,
+  0,
+  0);
+
+} // namespace ctl
@@ -0,0 +1,13 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef COSMOPOLITAN_CTL_DUBBLE_H_
+#define COSMOPOLITAN_CTL_DUBBLE_H_
+#include "third_party/double-conversion/double-to-string.h"
+
+namespace ctl {
+
+extern const double_conversion::DoubleToStringConverter kDoubleToPrintfG;
+
+} // namespace ctl
+
+#endif // COSMOPOLITAN_CTL_DUBBLE_H_
@@ -0,0 +1,23 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_ENABLE_IF_H_
+#define CTL_ENABLE_IF_H_
+
+namespace ctl {
+
+template<bool B, class T = void>
+struct enable_if
+{};
+
+template<class T>
+struct enable_if<true, T>
+{
+    typedef T type;
+};
+
+template<bool B, class T = void>
+using enable_if_t = typename enable_if<B, T>::type;
+
+} // namespace ctl
+
+#endif // CTL_ENABLE_IF_H_
@@ -0,0 +1,64 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_EQUAL_H_
+#define CTL_EQUAL_H_
+
+namespace ctl {
+
+template<class InputIt1, class InputIt2>
+bool
+equal(InputIt1 first1, InputIt1 last1, InputIt2 first2)
+{
+    for (; first1 != last1; ++first1, ++first2) {
+        if (!(*first1 == *first2)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+// Overload that takes a predicate
+template<class InputIt1, class InputIt2, class BinaryPredicate>
+bool
+equal(InputIt1 first1, InputIt1 last1, InputIt2 first2, BinaryPredicate pred)
+{
+    for (; first1 != last1; ++first1, ++first2) {
+        if (!pred(*first1, *first2)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+// Overloads that take two ranges (C++14 and later)
+template<class InputIt1, class InputIt2>
+bool
+equal(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2)
+{
+    for (; first1 != last1 && first2 != last2; ++first1, ++first2) {
+        if (!(*first1 == *first2)) {
+            return false;
+        }
+    }
+    return first1 == last1 && first2 == last2;
+}
+
+template<class InputIt1, class InputIt2, class BinaryPredicate>
+bool
+equal(InputIt1 first1,
+      InputIt1 last1,
+      InputIt2 first2,
+      InputIt2 last2,
+      BinaryPredicate pred)
+{
+    for (; first1 != last1 && first2 != last2; ++first1, ++first2) {
+        if (!pred(*first1, *first2)) {
+            return false;
+        }
+    }
+    return first1 == last1 && first2 == last2;
+}
+
+} // namespace ctl
+
+#endif /* CTL_EQUAL_H_ */
@@ -0,0 +1,22 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_EXCEPTION_H_
+#define CTL_EXCEPTION_H_
+
+namespace ctl {
+
+class exception
+{
+  public:
+    exception() noexcept = default;
+    virtual ~exception() = default;
+
+    virtual const char* what() const noexcept
+    {
+        return "ctl::exception";
+    }
+};
+
+} // namespace ctl
+
+#endif // CTL_EXCEPTION_H_
@@ -0,0 +1,18 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_FILL_H_
+#define CTL_FILL_H_
+
+namespace ctl {
+
+template<typename ForwardIt, typename T>
+void
+fill(ForwardIt first, ForwardIt last, const T& value)
+{
+    for (; first != last; ++first)
+        *first = value;
+}
+
+} // namespace ctl
+
+#endif // CTL_FILL_H_
@@ -0,0 +1,19 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_FILL_N_H_
+#define CTL_FILL_N_H_
+
+namespace ctl {
+
+template<typename OutputIt, typename Size, typename T>
+OutputIt
+fill_n(OutputIt first, Size count, const T& value)
+{
+    for (; count > 0; --count, ++first)
+        *first = value;
+    return first;
+}
+
+} // namespace ctl
+
+#endif // CTL_FILL_N_H_
@@ -0,0 +1,64 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef _LIBCPP_INITIALIZER_LIST
+#define _LIBCPP_INITIALIZER_LIST
+
+namespace std {
+
+template<class T>
+class initializer_list
+{
+    constexpr initializer_list(const T* b, size_t s) noexcept
+      : begin_(b), size_(s)
+    {
+    }
+
+  public:
+    typedef T value_type;
+    typedef const T& reference;
+    typedef const T& const_reference;
+    typedef size_t size_type;
+    typedef const T* iterator;
+    typedef const T* const_iterator;
+
+    constexpr initializer_list() noexcept : begin_(nullptr), size_(0)
+    {
+    }
+
+    constexpr size_t size() const noexcept
+    {
+        return size_;
+    }
+
+    constexpr const T* begin() const noexcept
+    {
+        return begin_;
+    }
+
+    constexpr const T* end() const noexcept
+    {
+        return begin_ + size_;
+    }
+
+  private:
+    const T* begin_;
+    size_t size_;
+};
+
+template<class T>
+inline constexpr const T*
+begin(initializer_list<T> i) noexcept
+{
+    return i.begin();
+}
+
+template<class T>
+inline constexpr const T*
+end(initializer_list<T> i) noexcept
+{
+    return i.end();
+}
+
+} // namespace std
+
+#endif // _LIBCPP_INITIALIZER_LIST
@@ -0,0 +1,31 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_INTEGRAL_CONSTANT_H_
+#define CTL_INTEGRAL_CONSTANT_H_
+
+namespace ctl {
+
+template<class T, T v>
+struct integral_constant
+{
+    static constexpr T value = v;
+    typedef T value_type;
+    typedef integral_constant type;
+
+    constexpr operator value_type() const noexcept
+    {
+        return value;
+    }
+
+    constexpr value_type operator()() const noexcept
+    {
+        return value;
+    }
+};
+
+typedef integral_constant<bool, true> true_type;
+typedef integral_constant<bool, false> false_type;
+
+} // namespace ctl
+
+#endif // CTL_INTEGRAL_CONSTANT_H_
@@ -0,0 +1,39 @@
+// -*- mode:c++; indent-tabs-mode:nil; c-basic-offset:4; coding:utf-8 -*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+//
+// Copyright 2024 Justine Alexandra Roberts Tunney
+//
+// Permission to use, copy, modify, and/or distribute this software for
+// any purpose with or without fee is hereby granted, provided that the
+// above copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+// WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+// AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+// DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+// PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include "ios.h"
+
+namespace ctl {
+
+ios::ios(FILE* file) : file_(file)
+{
+}
+
+ios::~ios() = default;
+
+ios&
+ios::operator=(ios&& other) noexcept
+{
+    if (this != &other) {
+        file_ = other.file_;
+        other.file_ = nullptr;
+    }
+    return *this;
+}
+
+} // namespace ctl
@@ -0,0 +1,27 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IOS_H_
+#define CTL_IOS_H_
+#include "ios_base.h"
+
+struct FILE;
+
+namespace ctl {
+
+class ios : public ios_base
+{
+  public:
+    explicit ios(FILE*);
+    virtual ~ios();
+
+  protected:
+    ios& operator=(ios&&) noexcept;
+    FILE* file_;
+
+  private:
+    ios(const ios&) = delete;
+};
+
+} // namespace ctl
+
+#endif // CTL_IOS_H_
@@ -0,0 +1,118 @@
+// -*- mode:c++; indent-tabs-mode:nil; c-basic-offset:4; coding:utf-8 -*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+//
+// Copyright 2024 Justine Alexandra Roberts Tunney
+//
+// Permission to use, copy, modify, and/or distribute this software for
+// any purpose with or without fee is hereby granted, provided that the
+// above copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+// WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+// AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+// DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+// PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include "ios_base.h"
+
+namespace ctl {
+
+ios_base::ios_base() : state_(goodbit), flags_(skipws | dec)
+{
+}
+
+ios_base::~ios_base() = default;
+
+ios_base::fmtflags
+ios_base::flags() const
+{
+    return static_cast<ios_base::fmtflags>(flags_);
+}
+
+ios_base::fmtflags
+ios_base::flags(fmtflags fmtfl)
+{
+    int old = flags_;
+    flags_ = fmtfl;
+    return static_cast<ios_base::fmtflags>(old);
+}
+
+ios_base::fmtflags
+ios_base::setf(fmtflags fmtfl)
+{
+    int old = flags_;
+    flags_ |= fmtfl;
+    return static_cast<ios_base::fmtflags>(old);
+}
+
+ios_base::fmtflags
+ios_base::setf(fmtflags fmtfl, fmtflags mask)
+{
+    int old = flags_;
+    flags_ = (flags_ & ~mask) | (fmtfl & mask);
+    return static_cast<ios_base::fmtflags>(old);
+}
+
+void
+ios_base::unsetf(fmtflags mask)
+{
+    flags_ &= ~mask;
+}
+
+ios_base::iostate
+ios_base::rdstate() const
+{
+    return static_cast<ios_base::iostate>(state_);
+}
+
+void
+ios_base::clear(int state)
+{
+    state_ = state;
+}
+
+void
+ios_base::setstate(int state)
+{
+    state_ |= state;
+}
+
+bool
+ios_base::good() const
+{
+    return state_ == goodbit;
+}
+
+bool
+ios_base::eof() const
+{
+    return (state_ & eofbit) != 0;
+}
+
+bool
+ios_base::fail() const
+{
+    return (state_ & (failbit | badbit)) != 0;
+}
+
+bool
+ios_base::bad() const
+{
+    return (state_ & badbit) != 0;
+}
+
+bool
+ios_base::operator!() const
+{
+    return fail();
+}
+
+ios_base::operator bool() const
+{
+    return !fail();
+}
+
+} // namespace ctl
@@ -0,0 +1,86 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IOS_BASE_H_
+#define CTL_IOS_BASE_H_
+
+namespace ctl {
+
+class ios_base
+{
+  public:
+    typedef size_t streamsize;
+
+    enum iostate
+    {
+        goodbit = 0,
+        badbit = 1,
+        failbit = 2,
+        eofbit = 4
+    };
+
+    enum fmtflags
+    {
+        boolalpha = 1 << 0,
+        dec = 1 << 1,
+        fixed = 1 << 2,
+        hex = 1 << 3,
+        internal = 1 << 4,
+        left = 1 << 5,
+        oct = 1 << 6,
+        right = 1 << 7,
+        scientific = 1 << 8,
+        showbase = 1 << 9,
+        showpoint = 1 << 10,
+        showpos = 1 << 11,
+        skipws = 1 << 12,
+        unitbuf = 1 << 13,
+        uppercase = 1 << 14,
+        adjustfield = left | right | internal,
+        basefield = dec | oct | hex,
+        floatfield = scientific | fixed
+    };
+
+    enum openmode
+    {
+        app = 1 << 0,
+        binary = 1 << 1,
+        in = 1 << 2,
+        out = 1 << 3,
+        trunc = 1 << 4,
+        ate = 1 << 5
+    };
+
+  protected:
+    ios_base();
+    virtual ~ios_base();
+
+    int state_;
+    int flags_;
+
+  public:
+    fmtflags flags() const;
+    fmtflags flags(fmtflags);
+    fmtflags setf(fmtflags);
+    fmtflags setf(fmtflags, fmtflags);
+    void unsetf(fmtflags);
+
+    iostate rdstate() const;
+    void clear(int = goodbit);
+    void setstate(int);
+
+    bool good() const;
+    bool eof() const;
+    bool fail() const;
+    bool bad() const;
+
+    bool operator!() const;
+    explicit operator bool() const;
+
+  private:
+    ios_base(const ios_base&) = delete;
+    ios_base& operator=(const ios_base&) = delete;
+};
+
+} // namespace ctl
+
+#endif // CTL_IOS_BASE_H_
@@ -0,0 +1,18 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_ABSTRACT_H_
+#define CTL_IS_ABSTRACT_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_abstract : public ctl::integral_constant<bool, __is_abstract(T)>
+{};
+
+template<typename T>
+inline constexpr bool is_abstract_v = __is_abstract(T);
+
+} // namespace ctl
+
+#endif // CTL_IS_ABSTRACT_H_
@@ -0,0 +1,26 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_ARRAY_H_
+#define CTL_IS_ARRAY_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_array : ctl::false_type
+{};
+
+template<typename T, size_t N>
+struct is_array<T[N]> : ctl::true_type
+{};
+
+template<typename T>
+struct is_array<T[]> : ctl::true_type
+{};
+
+template<typename T>
+inline constexpr bool is_array_v = is_array<T>::value;
+
+} // namespace ctl
+
+#endif // CTL_IS_ARRAY_H_
@@ -0,0 +1,19 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_BASE_OF_H_
+#define CTL_IS_BASE_OF_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename Base, typename Derived>
+struct is_base_of
+  : public ctl::integral_constant<bool, __is_base_of(Base, Derived)>
+{};
+
+template<typename Base, typename Derived>
+inline constexpr bool is_base_of_v = __is_base_of(Base, Derived);
+
+} // namespace ctl
+
+#endif // CTL_IS_BASE_OF_H_
@@ -0,0 +1,18 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_CLASS_H_
+#define CTL_IS_CLASS_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_class : public ctl::integral_constant<bool, __is_class(T)>
+{};
+
+template<typename T>
+inline constexpr bool is_class_v = __is_class(T);
+
+} // namespace ctl
+
+#endif // CTL_IS_CLASS_H_
@@ -0,0 +1,19 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_CONSTRUCTIBLE_H_
+#define CTL_IS_CONSTRUCTIBLE_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<class _Tp, class... _Args>
+struct is_constructible
+  : public ctl::integral_constant<bool, __is_constructible(_Tp, _Args...)>
+{};
+
+template<class _Tp, class... _Args>
+inline constexpr bool is_constructible_v = __is_constructible(_Tp, _Args...);
+
+} // namespace ctl
+
+#endif // CTL_IS_CONSTRUCTIBLE_H_
@@ -0,0 +1,53 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_CONVERTIBLE_H_
+#define CTL_IS_CONVERTIBLE_H_
+#include "ctl/integral_constant.h"
+#include "ctl/void_t.h"
+
+namespace ctl {
+
+// Declaration of declval
+template<typename T>
+T&&
+declval() noexcept;
+
+namespace detail {
+
+template<typename From, typename To, typename = void>
+struct is_convertible_impl : ctl::false_type
+{};
+
+template<typename From, typename To>
+struct is_convertible_impl<From,
+                           To,
+                           void_t<decltype(static_cast<To>(declval<From>()))>>
+  : true_type
+{};
+
+// Handle void types separately
+template<>
+struct is_convertible_impl<void, void> : ctl::true_type
+{};
+
+template<typename To>
+struct is_convertible_impl<void, To> : ctl::false_type
+{};
+
+template<typename From>
+struct is_convertible_impl<From, void> : ctl::false_type
+{};
+
+} // namespace detail
+
+template<typename From, typename To>
+struct is_convertible : detail::is_convertible_impl<From, To>
+{};
+
+// Helper variable template (C++17 and later)
+template<typename From, typename To>
+inline constexpr bool is_convertible_v = is_convertible<From, To>::value;
+
+} // namespace ctl
+
+#endif // CTL_IS_CONVERTIBLE_H_
@@ -0,0 +1,18 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_EMPTY_H_
+#define CTL_IS_EMPTY_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_empty : public ctl::integral_constant<bool, __is_empty(T)>
+{};
+
+template<typename T>
+inline constexpr bool is_empty_v = __is_empty(T);
+
+} // namespace ctl
+
+#endif // CTL_IS_EMPTY_H_
@@ -0,0 +1,18 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_ENUM_H_
+#define CTL_IS_ENUM_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_enum : public ctl::integral_constant<bool, __is_enum(T)>
+{};
+
+template<typename T>
+inline constexpr bool is_enum_v = __is_enum(T);
+
+} // namespace ctl
+
+#endif // CTL_IS_ENUM_H_
@@ -0,0 +1,120 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_FUNCTION_H_
+#define CTL_IS_FUNCTION_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+// Primary template
+template<class>
+struct is_function : ctl::false_type
+{};
+
+// Specializations for various function types
+
+// Regular functions
+template<class Ret, class... Args>
+struct is_function<Ret(Args...)> : ctl::true_type
+{};
+
+// Functions with cv-qualifiers
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) const> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) volatile> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) const volatile> : ctl::true_type
+{};
+
+// Functions with ref-qualifiers
+template<class Ret, class... Args>
+struct is_function<Ret(Args...)&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) const&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) volatile&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) const volatile&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) &&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) const&&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) volatile&&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args...) const volatile&&> : ctl::true_type
+{};
+
+// Variadic functions
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...)> : ctl::true_type
+{};
+
+// Variadic functions with cv-qualifiers
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) const> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) volatile> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) const volatile> : ctl::true_type
+{};
+
+// Variadic functions with ref-qualifiers
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...)&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) const&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) volatile&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) const volatile&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) &&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) const&&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) volatile&&> : ctl::true_type
+{};
+
+template<class Ret, class... Args>
+struct is_function<Ret(Args..., ...) const volatile&&> : ctl::true_type
+{};
+
+} // namespace ctl
+
+#endif // CTL_IS_FUNCTION_H_
@@ -0,0 +1,78 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_INTEGRAL_H_
+#define CTL_IS_INTEGRAL_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_integral : ctl::false_type
+{};
+
+template<>
+struct is_integral<bool> : ctl::true_type
+{};
+
+template<>
+struct is_integral<char> : ctl::true_type
+{};
+
+template<>
+struct is_integral<signed char> : ctl::true_type
+{};
+
+template<>
+struct is_integral<unsigned char> : ctl::true_type
+{};
+
+template<>
+struct is_integral<short> : ctl::true_type
+{};
+
+template<>
+struct is_integral<unsigned short> : ctl::true_type
+{};
+
+template<>
+struct is_integral<int> : ctl::true_type
+{};
+
+template<>
+struct is_integral<unsigned int> : ctl::true_type
+{};
+
+template<>
+struct is_integral<long> : ctl::true_type
+{};
+
+template<>
+struct is_integral<unsigned long> : ctl::true_type
+{};
+
+template<>
+struct is_integral<long long> : ctl::true_type
+{};
+
+template<>
+struct is_integral<unsigned long long> : ctl::true_type
+{};
+
+template<>
+struct is_integral<char16_t> : ctl::true_type
+{};
+
+template<>
+struct is_integral<char32_t> : ctl::true_type
+{};
+
+template<>
+struct is_integral<wchar_t> : ctl::true_type
+{};
+
+template<typename T>
+inline constexpr bool is_integral_v = is_integral<T>::value;
+
+} // namespace ctl
+
+#endif // CTL_IS_INTEGRAL_H_
@@ -0,0 +1,18 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_POLYMORPHIC_H_
+#define CTL_IS_POLYMORPHIC_H_
+#include "integral_constant.h"
+
+namespace ctl {
+
+template<typename T>
+struct is_polymorphic : public ctl::integral_constant<bool, __is_polymorphic(T)>
+{};
+
+template<typename T>
+inline constexpr bool is_polymorphic_v = __is_polymorphic(T);
+
+} // namespace ctl
+
+#endif // CTL_IS_POLYMORPHIC_H_
@@ -0,0 +1,35 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_REFERENCE_H_
+#define CTL_IS_REFERENCE_H_
+
+namespace ctl {
+
+// Primary template
+template<class T>
+struct is_reference
+{
+    static constexpr bool value = false;
+};
+
+// Specialization for lvalue reference
+template<class T>
+struct is_reference<T&>
+{
+    static constexpr bool value = true;
+};
+
+// Specialization for rvalue reference
+template<class T>
+struct is_reference<T&&>
+{
+    static constexpr bool value = true;
+};
+
+// Helper variable template (C++14 and later)
+template<class T>
+inline constexpr bool is_reference_v = is_reference<T>::value;
+
+} // namespace ctl
+
+#endif // CTL_IS_REFERENCE_H_
@@ -0,0 +1,25 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_SAME_H_
+#define CTL_IS_SAME_H_
+
+namespace ctl {
+
+template<typename T, typename U>
+struct is_same
+{
+    static constexpr bool value = false;
+};
+
+template<typename T>
+struct is_same<T, T>
+{
+    static constexpr bool value = true;
+};
+
+template<class T, class U>
+inline constexpr bool is_same_v = is_same<T, U>::value;
+
+} // namespace ctl
+
+#endif // CTL_IS_SAME_H_
@@ -0,0 +1,16 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_IS_SIGNED_H_
+#define CTL_IS_SIGNED_H_
+
+namespace ctl {
+
+template<typename T>
+struct is_signed
+{
+    static constexpr bool value = T(0) > T(-1);
+};
+
+} // namespace ctl
+
+#endif // CTL_IS_SIGNED_H_