From b75e7687f430672a7f20c6e64df77c67e371680a Mon Sep 17 00:00:00 2001
From: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Date: Fri, 30 Jun 2023 01:20:48 +0200
Subject: [PATCH] all: CI and misc updates

---
 .github/workflows/ci.yml                      |   5 +-
 .github/workflows/test-alpine-linux.yml       |  50 +++++++-
 .github/workflows/weekly-ci-zigcc.yml         |   4 +-
 CMakeLists.txt                                |   9 +-
 .../10-create-image.sh                        |   4 +-
 .../11-list-packages.sh                       |   2 +-
 .../20-image-run-shell.sh                     |   4 +-
 misc/cross-compile-upx-with-podman/Dockerfile |   6 +-
 .../build-all-inside-container.sh             |   1 +
 .../packages.txt                              |  20 +++-
 .../10-create-image.sh                        |   2 +-
 .../11-list-packages.sh                       |   2 +-
 .../20-image-run-shell.sh                     |   4 +-
 misc/rebuild-stubs-with-podman/Dockerfile     |  26 ++--
 misc/rebuild-stubs-with-podman/packages.txt   |  20 +++-
 misc/scripts/build_upx_by_hand.sh             | 113 +++++++++++-------
 16 files changed, 192 insertions(+), 80 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4be52be3..9b1be8c2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,8 +11,8 @@ on: [push, workflow_dispatch]
 env:
   DEBIAN_FRONTEND: noninteractive
   UPX_CMAKE_BUILD_FLAGS: --verbose
-  # 2023-06-27
-  ZIG_DIST_VERSION: 0.11.0-dev.3859+88284c124
+  # 2023-06-29
+  ZIG_DIST_VERSION: 0.11.0-dev.3886+0c1bfe271
 
 jobs:
   job-rebuild-and-verify-stubs:
@@ -144,6 +144,7 @@ jobs:
         run: |
           # testsuite needs working "readlink -en" and "sha256sum"
           if ! test -e /usr/local/opt/coreutils/libexec/gnubin/readlink; then
+            echo "===== brew leaves:"; brew leaves; echo "===== brew list:"; brew list
             brew update
             brew install coreutils
           fi
diff --git a/.github/workflows/test-alpine-linux.yml b/.github/workflows/test-alpine-linux.yml
index bb05b1e6..2ebcd79f 100644
--- a/.github/workflows/test-alpine-linux.yml
+++ b/.github/workflows/test-alpine-linux.yml
@@ -58,8 +58,10 @@ jobs:
           name: ${{ env.artifact_name }}
           path: 'upx*/build/*/upx'
 
-  job-alpine-by-hand: # uses shell
-    # and also uses a subdirectory "upx with space" in order to detect possible quoting issues
+  job-alpine-by-hand: # uses a POSIX-compliant shell
+    # ...and also uses a subdirectory "upx with space" in order to detect possible quoting issues
+    # ...and also uses ccache as we are running the same build-script again and again
+    if: ${{ true }}
     strategy: { matrix: { container: ['alpine:3.9','alpine:edge'] } }
     name: ${{ format('gcc by-hand {0}', matrix.container) }}
     runs-on: ubuntu-latest
@@ -67,7 +69,15 @@ jobs:
     steps:
       - name: ${{ format('Install packages {0}', matrix.container) }}
         run: |
-          apk update && apk upgrade && apk add bash dash g++ git mksh zsh
+          # install ccache, g++, git and various POSIX shells
+          shells="bash dash loksh mksh zsh"
+          case ${{ matrix.container }} in
+            *:edge) shells="$shells oksh yash" ;;
+          esac
+          echo "installing shells: $shells"
+          apk update && apk upgrade && apk add ccache g++ git $shells
+          # enable ccache
+          echo -e "CC=ccache gcc\nCXX=ccache g++ -std=gnu++17" >> $GITHUB_ENV
           # this seems to be needed when running in a container (beause of UID mismatch??)
           git config --global --add safe.directory '*'
       - name: 'Check out code'
@@ -77,11 +87,45 @@ jobs:
           path: 'upx with space'
       - name: 'Build by-hand with bash'
         run: 'bash "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with bash --posix'
+        run: 'bash --posix "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with busybox ash'
+        run: 'busybox ash "./upx with space/misc/scripts/build_upx_by_hand.sh"'
       - name: 'Build by-hand with busybox sh'
         run: 'busybox sh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
       - name: 'Build by-hand with dash'
         run: 'dash "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with loksh'
+        run: 'ksh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with loksh -o posix'
+        run: 'ksh -o posix "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with loksh -o sh'
+        run: 'ksh -o sh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
       - name: 'Build by-hand with mksh'
         run: 'mksh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with mksh -o posix'
+        run: 'mksh -o posix "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with mksh -o sh'
+        run: 'mksh -o sh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with oksh'
+        if: ${{ contains(matrix.container, ':edge') }}
+        run: 'oksh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with oksh -o posix'
+        if: ${{ contains(matrix.container, ':edge') }}
+        run: 'oksh -o posix "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with oksh -o sh'
+        if: ${{ contains(matrix.container, ':edge') }}
+        run: 'oksh -o sh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with yash'
+        if: ${{ contains(matrix.container, ':edge') }}
+        run: 'yash "./upx with space/misc/scripts/build_upx_by_hand.sh"'
       - name: 'Build by-hand with zsh'
         run: 'zsh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with zsh --emulate ksh'
+        run: 'zsh --emulate ksh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Build by-hand with zsh --emulate sh'
+        run: 'zsh --emulate sh "./upx with space/misc/scripts/build_upx_by_hand.sh"'
+      - name: 'Show ccache stats'
+        run: |
+          ccache -s
+          ccache -p
diff --git a/.github/workflows/weekly-ci-zigcc.yml b/.github/workflows/weekly-ci-zigcc.yml
index 526f2655..4005519a 100644
--- a/.github/workflows/weekly-ci-zigcc.yml
+++ b/.github/workflows/weekly-ci-zigcc.yml
@@ -8,8 +8,8 @@ on:
   workflow_dispatch:
 
 env:
-  # 2023-06-27
-  ZIG_DIST_VERSION: 0.11.0-dev.3859+88284c124
+  # 2023-06-29
+  ZIG_DIST_VERSION: 0.11.0-dev.3886+0c1bfe271
 
 jobs:
   job-linux-zigcc: # uses cmake + make
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 177ad8b2..ebc14620 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -416,10 +416,6 @@ endif() # UPX_CONFIG_CMAKE_DISABLE_INSTALL
 # finally print some info about the build configuration
 #***********************************************************************
 
-if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/maint/make/CMakeLists.maint.txt")
-include("${CMAKE_CURRENT_SOURCE_DIR}/maint/make/CMakeLists.maint.txt")
-endif()
-
 function(print_var)
     foreach(v ${ARGV})
         if(${v})
@@ -427,6 +423,11 @@ function(print_var)
         endif()
     endforeach()
 endfunction()
+
+if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/maint/make/CMakeLists.maint.txt")
+include("${CMAKE_CURRENT_SOURCE_DIR}/maint/make/CMakeLists.maint.txt")
+endif()
+
 print_var(CMAKE_VERSION UPX_CONFIG_CMAKE_MINIMUM_REQUIRED_VERSION)
 if(NOT UPX_CONFIG_CMAKE_DISABLE_PRINT_INFO)
 print_var(CMAKE_HOST_SYSTEM_NAME CMAKE_HOST_SYSTEM_VERSION)
diff --git a/misc/cross-compile-upx-with-podman/10-create-image.sh b/misc/cross-compile-upx-with-podman/10-create-image.sh
index b04c14ea..a755bd6b 100755
--- a/misc/cross-compile-upx-with-podman/10-create-image.sh
+++ b/misc/cross-compile-upx-with-podman/10-create-image.sh
@@ -6,10 +6,10 @@ argv0=$0; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
 # create the image from Dockerfile
 # using a rootless Podman container
 
-# NOTE: this image is based on rebuild-stubs-with-podman/upx-stubtools-20221212-v5,
+# NOTE: this image is based on rebuild-stubs-with-podman/upx-stubtools-20221212-v6,
 #   so you have to create that image first
 # WARNING: we install many packages, so the resulting image needs A LOT of disk space!
-image=upx-cross-compile-20230115-v3
+image=upx-cross-compile-20230115-v4
 
 podman build -t "$image" -f "$argv0dir/Dockerfile" "$argv0dir"
 
diff --git a/misc/cross-compile-upx-with-podman/11-list-packages.sh b/misc/cross-compile-upx-with-podman/11-list-packages.sh
index bf2a8c0d..9150c112 100755
--- a/misc/cross-compile-upx-with-podman/11-list-packages.sh
+++ b/misc/cross-compile-upx-with-podman/11-list-packages.sh
@@ -6,7 +6,7 @@ argv0=$0; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
 # list all system packages that are installed in the image
 # using a rootless Podman container
 
-image=upx-cross-compile-20230115-v3
+image=upx-cross-compile-20230115-v4
 
 podman image list "$image"
 echo
diff --git a/misc/cross-compile-upx-with-podman/20-image-run-shell.sh b/misc/cross-compile-upx-with-podman/20-image-run-shell.sh
index 93ab4270..9d4d0ad4 100755
--- a/misc/cross-compile-upx-with-podman/20-image-run-shell.sh
+++ b/misc/cross-compile-upx-with-podman/20-image-run-shell.sh
@@ -6,7 +6,7 @@ argv0=$0; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
 # run an interactive shell in the image
 # using a rootless Podman container
 
-image=upx-cross-compile-20230115-v3
+image=upx-cross-compile-20230115-v4
 
 flags=( --read-only --rm --pull=never )
 flags+=( --cap-drop=all )               # drop all capabilities
@@ -23,6 +23,8 @@ if [[ 1 == 1 ]]; then
     # INFO: SELinux users *may* have to add ":z" to the volume mount flags; check the docs!
     flags+=( -v "${argv0dir}/../..:/home/upx/src/upx" )
     flags+=( -w /home/upx/src/upx )     # set working directory
+    flags+=( --tmpfs /home/upx/.cache:rw,exec ) # mount a writeable tmpfs
+    flags+=( --tmpfs /home/upx/.local:rw,exec ) # mount a writeable tmpfs
 else
     # run as user root 0:0
     # ONLY FOR DEBUGGING THE IMAGE
diff --git a/misc/cross-compile-upx-with-podman/Dockerfile b/misc/cross-compile-upx-with-podman/Dockerfile
index c55e2c44..1cedc3cb 100644
--- a/misc/cross-compile-upx-with-podman/Dockerfile
+++ b/misc/cross-compile-upx-with-podman/Dockerfile
@@ -1,8 +1,8 @@
-# NOTE: this image is based on rebuild-stubs-with-podman/upx-stubtools-20221212-v5,
+# NOTE: this image is based on rebuild-stubs-with-podman/upx-stubtools-20221212-v6,
 #   so you have to create that image first
 # WARNING: we install many packages, so the resulting image needs A LOT of disk space!
-FROM localhost/upx-stubtools-20221212-v5
-ENV UPX_CONTAINER_IMAGE_NAME=upx-cross-compile-20230115-v3
+FROM localhost/upx-stubtools-20221212-v6
+ENV UPX_CONTAINER_IMAGE_NAME=upx-cross-compile-20230115-v4
 ARG DEBIAN_FRONTEND=noninteractive
 
 USER root
diff --git a/misc/cross-compile-upx-with-podman/build-all-inside-container.sh b/misc/cross-compile-upx-with-podman/build-all-inside-container.sh
index bd5ca62a..9b5d0b57 100755
--- a/misc/cross-compile-upx-with-podman/build-all-inside-container.sh
+++ b/misc/cross-compile-upx-with-podman/build-all-inside-container.sh
@@ -15,6 +15,7 @@ fi
 # go to upx top-level directory
 cd "$argv0dir/../.." || exit 1
 pwd
+test -f doc/upx.pod   || exit 1 # sanity check
 test -f src/version.h || exit 1 # sanity check
 
 function run_config_and_build {
diff --git a/misc/cross-compile-upx-with-podman/packages.txt b/misc/cross-compile-upx-with-podman/packages.txt
index 4cf6bab6..96672396 100644
--- a/misc/cross-compile-upx-with-podman/packages.txt
+++ b/misc/cross-compile-upx-with-podman/packages.txt
@@ -41,9 +41,11 @@ ii  binutils-sparc64-linux-gnu                2.38-4ubuntu2.2
 ii  binutils-x86-64-linux-gnu                 2.38-4ubuntu2.2                         amd64        GNU binary utilities, for x86-64-linux-gnu target
 ii  binutils-x86-64-linux-gnux32              2.38-4ubuntu2.2                         amd64        GNU binary utilities, for x86-64-linux-gnux32 target
 ii  bsdutils                                  1:2.37.2-4ubuntu3                       amd64        basic utilities from 4.4BSD-Lite
+ii  busybox                                   1:1.30.1-7ubuntu3                       amd64        Tiny utilities for small and embedded systems
 ii  bzip2                                     1.0.8-5build1                           amd64        high-quality block-sorting file compressor - utilities
 ii  ca-certificates                           20230311ubuntu0.22.04.1                 all          Common CA certificates
 ii  cabextract                                1.9-3                                   amd64        Microsoft Cabinet file unpacker
+ii  ccache                                    4.5.1-1                                 amd64        Compiler cache for fast recompilation of C/C++ code
 ii  chrpath                                   0.16-2                                  amd64        Tool to edit the rpath in ELF binaries
 ii  clang-14                                  1:14.0.0-1ubuntu1                       amd64        C, C++ and Objective-C compiler
 ii  clang-format-14                           1:14.0.0-1ubuntu1                       amd64        Tool to format C/C++/Obj-C code
@@ -166,6 +168,7 @@ ii  g++-s390x-linux-gnu                       4:11.2.0-1ubuntu1
 ii  g++-sh4-linux-gnu                         4:11.2.0--1ubuntu1                      amd64        GNU C++ compiler for the sh4 architecture
 ii  g++-sparc64-linux-gnu                     4:11.2.0--1ubuntu1                      amd64        GNU C++ compiler for the sparc64 architecture
 ii  g++-x86-64-linux-gnux32                   4:11.2.0--1ubuntu1                      amd64        GNU C++ compiler for the x32 architecture
+ii  gawk                                      1:5.1.0-1build3                         amd64        GNU awk, a pattern scanning and processing language
 ii  gcc                                       4:11.2.0-1ubuntu1                       amd64        GNU C compiler
 ii  gcc-10-cross-base-mipsen                  10.3.0-1ubuntu1cross2                   all          GCC, the GNU Compiler Collection (library base package)
 ii  gcc-10-mips-linux-gnu                     10.3.0-1ubuntu1cross2                   amd64        GNU C compiler (cross compiler for mips architecture)
@@ -628,6 +631,7 @@ ii  libgudev-1.0-0:amd64                      1:237-2build1
 ii  libgudev-1.0-0:i386                       1:237-2build1                           i386         GObject-based wrapper library for libudev
 ii  libharfbuzz0b:amd64                       2.7.4-1ubuntu3.1                        amd64        OpenType text shaping engine (shared library)
 ii  libharfbuzz0b:i386                        2.7.4-1ubuntu3.1                        i386         OpenType text shaping engine (shared library)
+ii  libhiredis0.14:amd64                      0.14.1-2                                amd64        minimalistic C client library for Redis
 ii  libhogweed6:amd64                         3.7.3-1build2                           amd64        low level cryptographic library (public-key cryptos)
 ii  libhogweed6:i386                          3.7.3-1build2                           i386         low level cryptographic library (public-key cryptos)
 ii  libhwasan0-arm64-cross                    12.1.0-2ubuntu1~22.04cross1             all          AddressSanitizer -- a fast memory error detector
@@ -820,6 +824,7 @@ ii  libsensors5:i386                          1:3.6.0-7ubuntu1
 ii  libsepol2:amd64                           3.3-1build1                             amd64        SELinux library for manipulating binary security policies
 ii  libshout3:amd64                           2.4.5-1build3                           amd64        MP3/Ogg Vorbis broadcast streaming library
 ii  libshout3:i386                            2.4.5-1build3                           i386         MP3/Ogg Vorbis broadcast streaming library
+ii  libsigsegv2:amd64                         2.13-1ubuntu3                           amd64        Library for handling page faults in a portable way
 ii  libslang2:amd64                           2.3.2-5build4                           amd64        S-Lang programming library - runtime version
 ii  libslang2:i386                            2.3.2-5build4                           i386         S-Lang programming library - runtime version
 ii  libslirp0:amd64                           4.6.1-1build1                           amd64        General purpose TCP-IP emulator library
@@ -1070,7 +1075,7 @@ ii  linux-libc-dev-s390x-cross                5.15.0-22.22cross3
 ii  linux-libc-dev-sh4-cross                  5.15.0-22.22cross4                      all          Linux Kernel Headers for development (for cross-compiling)
 ii  linux-libc-dev-sparc64-cross              5.15.0-22.22cross4                      all          Linux Kernel Headers for development (for cross-compiling)
 ii  linux-libc-dev-x32-cross                  5.15.0-22.22cross4                      all          Linux Kernel Headers for development (for cross-compiling)
-ii  linux-libc-dev:amd64                      5.15.0-75.82                            amd64        Linux Kernel Headers for development
+ii  linux-libc-dev:amd64                      5.15.0-76.83                            amd64        Linux Kernel Headers for development
 ii  lldb-14                                   1:14.0.0-1ubuntu1                       amd64        Next generation, high-performance debugger
 ii  llvm-14                                   1:14.0.0-1ubuntu1                       amd64        Modular compiler and toolchain technologies
 ii  llvm-14-dev                               1:14.0.0-1ubuntu1                       amd64        Modular compiler and toolchain technologies, libraries and headers
@@ -1091,6 +1096,7 @@ ii  mesa-vulkan-drivers:i386                  22.2.5-0ubuntu0.1~22.04.3
 ii  mingw-w64-common                          8.0.0-1                                 all          Common files for Mingw-w64
 ii  mingw-w64-i686-dev                        8.0.0-1                                 all          Development files for MinGW-w64 targeting Win32
 ii  mingw-w64-x86-64-dev                      8.0.0-1                                 all          Development files for MinGW-w64 targeting Win64
+ii  mksh                                      59c-16                                  amd64        MirBSD Korn Shell
 ii  moreutils                                 0.66-1                                  amd64        additional Unix utilities
 ii  mount                                     2.37.2-4ubuntu3                         amd64        tools for mounting and manipulating filesystems
 ii  msr-tools                                 1.3-4                                   amd64        Utilities for modifying MSRs from userspace
@@ -1161,6 +1167,7 @@ ii  systemd-sysv                              249.11-0ubuntu3.9
 ii  systemd-timesyncd                         249.11-0ubuntu3.9                       amd64        minimalistic service to synchronize local time with NTP servers
 ii  sysvinit-utils                            3.01-1ubuntu1                           amd64        System-V-like utilities
 ii  tar                                       1.34+dfsg-1ubuntu0.1.22.04.1            amd64        GNU version of the tar archiving utility
+ii  time                                      1.9-0.1build2                           amd64        GNU time program for measuring CPU resource usage
 ii  ubuntu-keyring                            2021.03.26                              all          GnuPG keys of the Ubuntu archive
 ii  ubuntu-mono                               20.10-0ubuntu2                          all          Ubuntu Mono Icon theme
 ii  ucf                                       3.0043                                  all          Update Configuration File(s): preserve user changes to config files
@@ -1181,6 +1188,7 @@ ii  xdg-user-dirs                             0.17-2ubuntu4
 ii  xkb-data                                  2.33-1                                  all          X Keyboard Extension (XKB) configuration data
 ii  xxd                                       2:8.2.3995-1ubuntu2.8                   amd64        tool to make (or reverse) a hex dump
 ii  xz-utils                                  5.2.5-2ubuntu1                          amd64        XZ-format compression utilities
+ii  yash                                      2.51-1                                  amd64        yet another shell
 ii  zip                                       3.0-12build2                            amd64        Archiver for .zip files
 ii  zlib1g-dev:amd64                          1:1.2.11.dfsg-2ubuntu9.2                amd64        compression library - development
 ii  zlib1g:amd64                              1:1.2.11.dfsg-2ubuntu9.2                amd64        compression library - runtime
@@ -1193,7 +1201,7 @@ ii  zstd                                      1.4.8+dfsg-3build1
 ||/ Name                                      Version                                 Architecture Description
 
 Packages sorted by Installed-Size:
-  7715290 ===== TOTAL (1187 packages)
+  7722308 ===== TOTAL (1195 packages)
    474522 libwine                                  i386
    270993 llvm-14-dev                              amd64
    264247 qemu-efi-aarch64                         all
@@ -1549,11 +1557,13 @@ Packages sorted by Installed-Size:
      1746 libunistring2                            amd64
      1730 libsdl2-2.0-0                            amd64
      1695 libgcc-11-dev-alpha-cross                all
+     1680 gawk                                     amd64
      1655 zstd                                     amd64
      1628 libslang2                                amd64
      1602 libsqlite3-0                             amd64
      1534 libcairo2                                i386
      1516 e2fsprogs                                amd64
+     1508 mksh                                     amd64
      1487 libstdc++6-armhf-cross                   all
      1484 libsamplerate0                           amd64
      1483 libsamplerate0                           i386
@@ -1562,6 +1572,7 @@ Packages sorted by Installed-Size:
      1455 libx11-6                                 i386
      1445 hyperfine                                amd64
      1436 libobjc-11-dev                           amd64
+     1429 yash                                     amd64
      1429 libx11-data                              all
      1425 libp11-kit0                              i386
      1408 llvm-14-runtime                          amd64
@@ -1571,6 +1582,7 @@ Packages sorted by Installed-Size:
      1373 libslang2                                i386
      1354 libgcrypt20                              amd64
      1351 libcairo2                                amd64
+     1343 ccache                                   amd64
      1328 libzstd-dev                              amd64
      1292 libp11-kit0                              amd64
      1285 libasound2                               i386
@@ -1619,6 +1631,7 @@ Packages sorted by Installed-Size:
       806 libsoup2.4-1                             i386
       794 rsync                                    amd64
       793 libbrotli1                               i386
+      791 busybox                                  amd64
       787 libcurl4                                 amd64
       784 libbrotli1                               amd64
       783 libcups2                                 amd64
@@ -2035,6 +2048,7 @@ Packages sorted by Installed-Size:
       130 dbus-user-session                        amd64
       128 libtasn1-6                               i386
       128 libdrm2                                  amd64
+      126 time                                     amd64
       125 libmpc3                                  amd64
       125 libitm1-alpha-cross                      all
       123 libtimedate-perl                         all
@@ -2103,6 +2117,7 @@ Packages sorted by Installed-Size:
        94 libcairo-gobject2                        i386
        93 libsasl2-modules-db                      amd64
        92 libsasl2-modules-db                      i386
+       92 libhiredis0.14                           amd64
        92 libgsm1                                  i386
        92 libgcc-s1-sparc64-cross                  all
        92 libgcc-s1-riscv64-cross                  all
@@ -2206,6 +2221,7 @@ Packages sorted by Installed-Size:
        50 libkeyutils1                             i386
        50 glib-networking-services                 amd64
        50 gcc                                      amd64
+       49 libsigsegv2                              amd64
        48 libxtst6                                 amd64
        48 libatomic1-armel-cross                   all
        48 glib-networking-common                   all
diff --git a/misc/rebuild-stubs-with-podman/10-create-image.sh b/misc/rebuild-stubs-with-podman/10-create-image.sh
index 300f7fbf..fd0ab06e 100755
--- a/misc/rebuild-stubs-with-podman/10-create-image.sh
+++ b/misc/rebuild-stubs-with-podman/10-create-image.sh
@@ -6,7 +6,7 @@ argv0=$0; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
 # create the image from Dockerfile
 # using a rootless Podman container
 
-image=upx-stubtools-20221212-v5
+image=upx-stubtools-20221212-v6
 
 podman build -t "$image" -f "$argv0dir/Dockerfile" "$argv0dir"
 
diff --git a/misc/rebuild-stubs-with-podman/11-list-packages.sh b/misc/rebuild-stubs-with-podman/11-list-packages.sh
index 8c18dca7..64cd04e4 100755
--- a/misc/rebuild-stubs-with-podman/11-list-packages.sh
+++ b/misc/rebuild-stubs-with-podman/11-list-packages.sh
@@ -6,7 +6,7 @@ argv0=$0; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
 # list all system packages that are installed in the image
 # using a rootless Podman container
 
-image=upx-stubtools-20221212-v5
+image=upx-stubtools-20221212-v6
 
 podman image list "$image"
 echo
diff --git a/misc/rebuild-stubs-with-podman/20-image-run-shell.sh b/misc/rebuild-stubs-with-podman/20-image-run-shell.sh
index 6958cf4c..0e49a74b 100755
--- a/misc/rebuild-stubs-with-podman/20-image-run-shell.sh
+++ b/misc/rebuild-stubs-with-podman/20-image-run-shell.sh
@@ -6,7 +6,7 @@ argv0=$0; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
 # run an interactive shell in the image
 # using a rootless Podman container
 
-image=upx-stubtools-20221212-v5
+image=upx-stubtools-20221212-v6
 
 flags=( --read-only --rm --pull=never )
 flags+=( --cap-drop=all )               # drop all capabilities
@@ -23,6 +23,8 @@ if [[ 1 == 1 ]]; then
     # INFO: SELinux users *may* have to add ":z" to the volume mount flags; check the docs!
     flags+=( -v "${argv0dir}/../..:/home/upx/src/upx" )
     flags+=( -w /home/upx/src/upx )     # set working directory
+    flags+=( --tmpfs /home/upx/.cache:rw,exec ) # mount a writeable tmpfs
+    flags+=( --tmpfs /home/upx/.local:rw,exec ) # mount a writeable tmpfs
 else
     # run as user root 0:0
     # ONLY FOR DEBUGGING THE IMAGE
diff --git a/misc/rebuild-stubs-with-podman/Dockerfile b/misc/rebuild-stubs-with-podman/Dockerfile
index 4c561f92..4b64dbf6 100644
--- a/misc/rebuild-stubs-with-podman/Dockerfile
+++ b/misc/rebuild-stubs-with-podman/Dockerfile
@@ -1,5 +1,5 @@
 FROM docker.io/library/ubuntu:22.04
-ENV UPX_CONTAINER_IMAGE_NAME=upx-stubtools-20221212-v5
+ENV UPX_CONTAINER_IMAGE_NAME=upx-stubtools-20221212-v6
 ARG DEBIAN_FRONTEND=noninteractive
 ENV LANG=C.UTF-8
 
@@ -7,16 +7,16 @@ ENV LANG=C.UTF-8
 RUN dpkg --add-architecture i386 \
     && apt-get update && apt-get upgrade -y \
     && apt-get install -y --no-install-recommends \
-        aria2 bash-completion ca-certificates git less libmpc3 libncurses5 \
-        make ncurses-term perl-base python2-minimal wget xz-utils \
+        aria2 bash bash-completion ca-certificates dash git less libmpc3 libncurses5 \
+        make ncurses-term perl-base python2-minimal time wget xz-utils \
         libc6:i386 zlib1g:i386 \
         # the following packages are not required for rebuilding the stubs, but
-        # they do make the image much more convenient and also allow building
+        # they do make the image *much* more convenient and also allow building
         # the full UPX binary inside the container via CMake:
-        7zip bfs bzip2 cabextract chrpath cmake cpio curl elfutils fd-find file fzf g++ gdb gojq \
-        ht htop hyperfine jq libzstd-dev lsb-release lz4 lzip lzop moreutils ninja-build \
-        p7zip parallel patch patchelf pax-utils paxctl re2c ripgrep rsync \
-        screen universal-ctags unzip vim zip zlib1g-dev zsh zstd \
+        7zip bfs busybox bzip2 cabextract ccache chrpath cmake cpio curl elfutils fd-find file fzf \
+        g++ gawk gdb gojq ht htop hyperfine jq libzstd-dev lsb-release lz4 lzip lzop \
+        mksh moreutils ninja-build p7zip parallel patch patchelf pax-utils paxctl \
+        re2c ripgrep rsync screen universal-ctags unzip vim yash zip zlib1g-dev zsh zstd \
         # extra packages for compiling with "gcc -m32" and and "gcc -mx32":
         g++-multilib gcc-multilib \
     && true
@@ -52,8 +52,12 @@ RUN cd /root \
 
 # create default user upx 2000:2000
 RUN useradd upx -U --uid 2000 --shell /bin/bash -m \
-    && mkdir -p /home/upx/.cache/zig /home/upx/.local/bin /home/upx/.wine /home/upx/src/upx \
-    && ln -s /usr/local/bin/bin-upx-20221212 /home/upx/.local/bin/bin-upx \
-    && chown -R upx:upx /home/upx \
+    && cd /home/upx && chmod 700 . \
+    && mkdir -p .cache .local src/upx \
+    && for d in ccache go-build tmp wine zig; do mkdir -p .cache/$d; done \
+    && for d in bin share state; do mkdir -p .local/$d; done \
+    && ln -s .cache/wine .wine && ln -s .cache/tmp tmp \
+    && ln -s /usr/local/bin/bin-upx-20221212 .local/bin/bin-upx \
+    && chown -R upx:upx . \
     && true
 USER upx
diff --git a/misc/rebuild-stubs-with-podman/packages.txt b/misc/rebuild-stubs-with-podman/packages.txt
index c63ea907..cceda5ed 100644
--- a/misc/rebuild-stubs-with-podman/packages.txt
+++ b/misc/rebuild-stubs-with-podman/packages.txt
@@ -14,9 +14,11 @@ ii  binutils                    2.38-4ubuntu2.2                         amd64
 ii  binutils-common:amd64       2.38-4ubuntu2.2                         amd64        Common files for the GNU assembler, linker and binary utilities
 ii  binutils-x86-64-linux-gnu   2.38-4ubuntu2.2                         amd64        GNU binary utilities, for x86-64-linux-gnu target
 ii  bsdutils                    1:2.37.2-4ubuntu3                       amd64        basic utilities from 4.4BSD-Lite
+ii  busybox                     1:1.30.1-7ubuntu3                       amd64        Tiny utilities for small and embedded systems
 ii  bzip2                       1.0.8-5build1                           amd64        high-quality block-sorting file compressor - utilities
 ii  ca-certificates             20230311ubuntu0.22.04.1                 all          Common CA certificates
 ii  cabextract                  1.9-3                                   amd64        Microsoft Cabinet file unpacker
+ii  ccache                      4.5.1-1                                 amd64        Compiler cache for fast recompilation of C/C++ code
 ii  chrpath                     0.16-2                                  amd64        Tool to edit the rpath in ELF binaries
 ii  cmake                       3.22.1-1ubuntu1.22.04.1                 amd64        cross-platform, open-source make system
 ii  cmake-data                  3.22.1-1ubuntu1.22.04.1                 all          CMake data files (modules, templates and documentation)
@@ -43,6 +45,7 @@ ii  g++                         4:11.2.0-1ubuntu1                       amd64
 ii  g++-11                      11.3.0-1ubuntu1~22.04.1                 amd64        GNU C++ compiler
 ii  g++-11-multilib             11.3.0-1ubuntu1~22.04.1                 amd64        GNU C++ compiler (multilib support)
 ii  g++-multilib                4:11.2.0-1ubuntu1                       amd64        GNU C++ compiler (multilib files)
+ii  gawk                        1:5.1.0-1build3                         amd64        GNU awk, a pattern scanning and processing language
 ii  gcc                         4:11.2.0-1ubuntu1                       amd64        GNU C compiler
 ii  gcc-11                      11.3.0-1ubuntu1~22.04.1                 amd64        GNU C compiler
 ii  gcc-11-base:amd64           11.3.0-1ubuntu1~22.04.1                 amd64        GCC, the GNU Compiler Collection (base package)
@@ -135,6 +138,7 @@ ii  libgomp1:amd64              12.1.0-2ubuntu1~22.04                   amd64
 ii  libgpg-error0:amd64         1.43-3                                  amd64        GnuPG development runtime library
 ii  libgpm2:amd64               1.20.7-10build1                         amd64        General Purpose Mouse - shared library
 ii  libgssapi-krb5-2:amd64      1.19.2-2ubuntu0.2                       amd64        MIT Kerberos runtime libraries - krb5 GSS-API Mechanism
+ii  libhiredis0.14:amd64        0.14.1-2                                amd64        minimalistic C client library for Redis
 ii  libhogweed6:amd64           3.7.3-1build2                           amd64        low level cryptographic library (public-key cryptos)
 ii  libicu70:amd64              70.1-2                                  amd64        International Components for Unicode
 ii  libidn2-0:amd64             2.3.2-2build1                           amd64        Internationalized domain names (IDNA2008/TR46) library
@@ -202,6 +206,7 @@ ii  libsemanage2:amd64          3.3-1build2                             amd64
 ii  libsensors-config           1:3.6.0-7ubuntu1                        all          lm-sensors configuration files
 ii  libsensors5:amd64           1:3.6.0-7ubuntu1                        amd64        library to read temperature/voltage/fan sensors
 ii  libsepol2:amd64             3.3-1build1                             amd64        SELinux library for manipulating binary security policies
+ii  libsigsegv2:amd64           2.13-1ubuntu3                           amd64        Library for handling page faults in a portable way
 ii  libsmartcols1:amd64         2.37.2-4ubuntu3                         amd64        smart column output alignment library
 ii  libsodium23:amd64           1.0.18-1build2                          amd64        Network communication, cryptography and signaturing library
 ii  libsource-highlight-common  3.1.9-4.1build2                         all          architecture-independent files for source highlighting library
@@ -249,7 +254,7 @@ ii  libxxhash0:amd64            0.8.1-1                                 amd64
 ii  libyaml-0-2:amd64           0.2.2-1build2                           amd64        Fast YAML 1.1 parser and emitter library
 ii  libzstd-dev:amd64           1.4.8+dfsg-3build1                      amd64        fast lossless compression algorithm -- development files
 ii  libzstd1:amd64              1.4.8+dfsg-3build1                      amd64        fast lossless compression algorithm
-ii  linux-libc-dev:amd64        5.15.0-75.82                            amd64        Linux Kernel Headers for development
+ii  linux-libc-dev:amd64        5.15.0-76.83                            amd64        Linux Kernel Headers for development
 ii  login                       1:4.8.1-2ubuntu2.1                      amd64        system login tools
 ii  logsave                     1.46.5-2ubuntu1.1                       amd64        save the output of a command in a log file
 ii  lsb-base                    11.1.0ubuntu4                           all          Linux Standard Base init script functionality
@@ -260,6 +265,7 @@ ii  lzop                        1.04-2build2                            amd64
 ii  make                        4.3-4.1build1                           amd64        utility for directing compilation
 ii  mawk                        1.3.4.20200120-3                        amd64        Pattern scanning and text processing language
 ii  media-types                 7.0.0                                   all          List of standard media types and their usual file extension
+ii  mksh                        59c-16                                  amd64        MirBSD Korn Shell
 ii  moreutils                   0.66-1                                  amd64        additional Unix utilities
 ii  mount                       2.37.2-4ubuntu3                         amd64        tools for mounting and manipulating filesystems
 ii  ncurses-base                6.3-2ubuntu0.1                          all          basic terminal type definitions
@@ -295,6 +301,7 @@ ii  sensible-utils              0.0.17                                  all
 ii  sysstat                     12.5.2-2ubuntu0.2                       amd64        system performance tools for Linux
 ii  sysvinit-utils              3.01-1ubuntu1                           amd64        System-V-like utilities
 ii  tar                         1.34+dfsg-1ubuntu0.1.22.04.1            amd64        GNU version of the tar archiving utility
+ii  time                        1.9-0.1build2                           amd64        GNU time program for measuring CPU resource usage
 ii  ubuntu-keyring              2021.03.26                              all          GnuPG keys of the Ubuntu archive
 ii  ucf                         3.0043                                  all          Update Configuration File(s): preserve user changes to config files
 ii  universal-ctags             5.9.20210829.0-1                        amd64        build tag file indexes of source code definitions
@@ -307,6 +314,7 @@ ii  vim-runtime                 2:8.2.3995-1ubuntu2.8                   all
 ii  wget                        1.21.2-2ubuntu1                         amd64        retrieves files from the web
 ii  xxd                         2:8.2.3995-1ubuntu2.8                   amd64        tool to make (or reverse) a hex dump
 ii  xz-utils                    5.2.5-2ubuntu1                          amd64        XZ-format compression utilities
+ii  yash                        2.51-1                                  amd64        yet another shell
 ii  zip                         3.0-12build2                            amd64        Archiver for .zip files
 ii  zlib1g-dev:amd64            1:1.2.11.dfsg-2ubuntu9.2                amd64        compression library - development
 ii  zlib1g:amd64                1:1.2.11.dfsg-2ubuntu9.2                amd64        compression library - runtime
@@ -319,7 +327,7 @@ ii  zstd                        1.4.8+dfsg-3build1                      amd64
 ||/ Name                        Version                                 Architecture Description
 
 Packages sorted by Installed-Size:
-   741791 ===== TOTAL (313 packages)
+   748809 ===== TOTAL (321 packages)
     52577 gcc-11                                   amd64
     34444 libicu70                                 amd64
     32780 vim-runtime                              all
@@ -401,16 +409,20 @@ Packages sorted by Installed-Size:
      1854 aria2                                    amd64
      1750 libdb5.3                                 amd64
      1746 libunistring2                            amd64
+     1680 gawk                                     amd64
      1655 zstd                                     amd64
      1602 libsqlite3-0                             amd64
      1516 e2fsprogs                                amd64
+     1508 mksh                                     amd64
      1472 sysstat                                  amd64
      1464 bash-completion                          all
      1445 hyperfine                                amd64
+     1429 yash                                     amd64
      1429 libx11-data                              all
      1388 procps                                   amd64
      1386 libx11-6                                 amd64
      1354 libgcrypt20                              amd64
+     1343 ccache                                   amd64
      1328 libzstd-dev                              amd64
      1292 libp11-kit0                              amd64
      1138 libpam-modules                           amd64
@@ -424,6 +436,7 @@ Packages sorted by Installed-Size:
       876 libarchive13                             amd64
       846 libzstd1                                 amd64
       794 rsync                                    amd64
+      791 busybox                                  amd64
       787 libcurl4                                 amd64
       784 libbrotli1                               amd64
       771 libcurl3-gnutls                          amd64
@@ -558,6 +571,7 @@ Packages sorted by Installed-Size:
       133 init-system-helpers                      all
       132 libipt2                                  amd64
       131 libprocps8                               amd64
+      126 time                                     amd64
       125 libmpc3                                  amd64
       123 libtimedate-perl                         all
       123 libnsl2                                  amd64
@@ -583,6 +597,7 @@ Packages sorted by Installed-Size:
        96 libmspack0                               amd64
        95 libpsl5                                  amd64
        93 libsasl2-modules-db                      amd64
+       92 libhiredis0.14                           amd64
        91 libjansson4                              amd64
        90 python3                                  amd64
        83 sysvinit-utils                           amd64
@@ -608,6 +623,7 @@ Packages sorted by Installed-Size:
        51 libutempter0                             amd64
        51 hostname                                 amd64
        50 gcc                                      amd64
+       49 libsigsegv2                              amd64
        47 libkeyutils1                             amd64
        45 libgdbm-compat4                          amd64
        45 libcap-ng0                               amd64
diff --git a/misc/scripts/build_upx_by_hand.sh b/misc/scripts/build_upx_by_hand.sh
index a06784a3..cc8a1fe0 100755
--- a/misc/scripts/build_upx_by_hand.sh
+++ b/misc/scripts/build_upx_by_hand.sh
@@ -3,49 +3,78 @@
 set -e
 
 #
-# build UPX "by hand", using POSIX shell and a minimal number of compilation flags
+# build UPX "by hand", using a POSIX-compliant shell and
+# a minimal number of compilation flags
 # Copyright (C) Markus Franz Xaver Johannes Oberhumer
 #
 
+# uses optional environment variables: AR, CC, CXX, OPTIMIZE, top_srcdir
+
 # shell init
 ### set -x # enable logging
 DUALCASE=1; export DUALCASE # for MKS sh
 test -n "${ZSH_VERSION+set}" && emulate sh # for zsh
-argv0="$0"; argv0abs="$(readlink -fn "$argv0")"; argv0dir="$(dirname "$argv0abs")"
-# HINT: set "argv0dir" manually if your system does not have "readlink"
+my_argv0="$0"
 
-# toolchain settings and flags
+# toolchain settings and compilation flags
+AR="${AR:-ar}"
 CC="${CC:-cc}"
 CXX="${CXX:-c++ -std=gnu++17}"
-AR="${AR:-ar}"
 # HINT: use "export AR=false" if "$AR rcs" does not work on your system; see below
 if test "x$AR" = "x0" || test "x$AR" = "xfalse" || test "x$AR" = "x/bin/false"; then
     AR="" # do not use $AR
 fi
 # protect against security threats caused by misguided compiler "optimizations"
 mandatory_flags="-fno-strict-aliasing -fno-strict-overflow -funsigned-char"
-# not mandatory and not minimal, but usually a good idea:
-### mandatory_flags="-Wall -O2 $mandatory_flags"
+if test "x$OPTIMIZE" != "x" && test "x$OPTIMIZE" != "x0"; then
+    # not mandatory and not minimal, but usually a good idea:
+    mandatory_flags="-Wall -O2 $mandatory_flags"
+fi
 CC="$CC $mandatory_flags"
 CXX="$CXX $mandatory_flags"
 
 # go to upx top-level directory
-cd "$argv0dir/../.." || exit 1
-pwd
+# HINT: set "top_srcdir" manually if your system does not have "readlink"
+if test "x$top_srcdir" = "x"; then
+    my_argv0abs="$(readlink -fn "$my_argv0")"
+    my_argv0dir="$(dirname "$my_argv0abs")"
+    cd "$my_argv0dir/../.." || exit 1
+else
+    cd "$top_srcdir" || exit 1
+fi
+top_srcdir="$(pwd)"             # absolute
+rel_top_srcdir=.                # relative top_srcdir
+echo "# current directory: '$(pwd)'"
+test -f doc/upx.pod   || exit 1 # sanity check
 test -f src/version.h || exit 1 # sanity check
-top_srcdir="$PWD"
 rm -rf ./build/by-hand          # WARNING: existing build-directory gets deleted!
-mkdir -p ./build/by-hand
+
+# helper function
+run() {
+    if test 0 = 1; then
+        # DEBUG dry-run: print command, but don't actually run unless $1 is "+"
+        if test "x$1" = "x+"; then
+            shift; echo "$@"; "$@"; return
+        fi
+        shift; echo "$@"; return
+    fi
+    # print short info and run command
+    test "x$1" != "x" && test "x$1" != "x+" && echo "$1"
+    shift; "$@"
+}
 
 # helper function
 check_submodule() {
-    local f
-    for f in COPYING LICENSE LICENSE.txt; do
-        if test -f "$top_srcdir/vendor/$1/$f"; then
-            # create and enter build directory
-            mkdir -p "$top_srcdir/build/by-hand/$1"
-            cd "$top_srcdir/build/by-hand/$1" || exit 1
-            echo "===== build $1 ====="
+    #local ff # "local" seems unsupported by some versions of ksh
+    for ff in COPYING LICENSE LICENSE.txt; do
+        if test -f "$rel_top_srcdir/vendor/$1/$ff"; then
+            # create and enter build directory; updates global $rel_top_srcdir
+            run "+" cd "$rel_top_srcdir" || exit 1
+            rel_top_srcdir=.
+            echo "#==== build $1 ====="
+            run "+" mkdir "build/by-hand/$1"
+            run "+" cd "build/by-hand/$1" || exit 1
+            rel_top_srcdir=../../..
             return 0
         fi
     done
@@ -53,48 +82,44 @@ check_submodule() {
 }
 
 # build
+run "+" mkdir -p "build/by-hand"
 if check_submodule bzip2; then
-    for f in "$top_srcdir"/vendor/bzip2/*.c; do
-        echo "CC  $f"
-        $CC -c "$f"
+    for f in "$rel_top_srcdir"/vendor/bzip2/*.c; do
+        run "CC  $f" $CC -c "$f"
     done
 fi
 if check_submodule ucl; then
-    for f in "$top_srcdir"/vendor/ucl/src/*.c; do
-        echo "CC  $f"
-        $CC -I"$top_srcdir"/vendor/ucl/include -I"$top_srcdir"/vendor/ucl -c "$f"
+    for f in "$rel_top_srcdir"/vendor/ucl/src/*.c; do
+        run "CC  $f" $CC -I"$rel_top_srcdir"/vendor/ucl/include -I"$rel_top_srcdir"/vendor/ucl -c "$f"
     done
 fi
 if check_submodule zlib; then
-    for f in "$top_srcdir"/vendor/zlib/*.c; do
-        echo "CC  $f"
-        $CC -DHAVE_STDARG_H -DHAVE_VSNPRINTF -DHAVE_UNISTD_H -c "$f"
+    for f in "$rel_top_srcdir"/vendor/zlib/*.c; do
+        run "CC  $f" $CC -DHAVE_STDARG_H -DHAVE_VSNPRINTF -DHAVE_UNISTD_H -c "$f"
     done
 fi
 if check_submodule zstd; then
-    for f in "$top_srcdir"/vendor/zstd/lib/*/*.c; do
-        echo "CC  $f"
-        $CC -DDYNAMIC_BMI2=0 -DZSTD_DISABLE_ASM -c "$f"
+    for f in "$rel_top_srcdir"/vendor/zstd/lib/*/*.c; do
+        run "CC  $f" $CC -DDYNAMIC_BMI2=0 -DZSTD_DISABLE_ASM -c "$f"
     done
 fi
-echo "===== build UPX ====="
-cd "$top_srcdir"/build/by-hand || exit 1
-for f in "$top_srcdir"/src/*.cpp "$top_srcdir"/src/*/*.cpp; do
-    echo "CXX $f"
-    $CXX -I"$top_srcdir"/vendor -c "$f"
+run "+" cd "$rel_top_srcdir" || exit 1
+rel_top_srcdir=.
+echo "#==== build UPX ====="
+run "+" cd "build/by-hand" || exit 1
+rel_top_srcdir=../..
+for f in "$rel_top_srcdir"/src/*.cpp "$rel_top_srcdir"/src/*/*.cpp; do
+    run "CXX $f"     $CXX -I"$rel_top_srcdir"/vendor -c "$f"
 done
-# echo "===== link UPX ====="
+# echo "#==== link UPX ====="
 if test "x$AR" = "x"; then
     # link without using $AR
-    echo "CXX upx"
-    $CXX -o upx *.o */*.o
+    run "CXX upx"    $CXX -o upx *.o */*.o
 else
-    echo "AR  libupx"
-    $AR rcs libupx_submodules.a */*.o
-    echo "CXX upx"
-    $CXX -o upx *.o -L. -lupx_submodules
+    run "AR  libupx" $AR rcs libupx_submodules.a */*.o
+    run "CXX upx"    $CXX -o upx *.o -L. -lupx_submodules
 fi
-pwd
+echo "# current directory: '$(pwd)'"
 ls -l upx*
 
-echo "All done."
+echo "# All done."