Bug 1709253 - Fix building rust programs. r=firefox-build-system-reviewers,mhentges

Differential Revision: https://phabricator.services.mozilla.com/D114212

build/win32/dummy_libs.py

@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+import subprocess
+from buildconfig import substs
+
+
+def main(output, *other_libs):
+    output.close()
+    # ar doesn't like it when the file exists beforehand.
+    os.unlink(output.name)
+    libs = [output.name]
+    parent = os.path.dirname(output.name)
+    libs.extend(os.path.join(parent, l) for l in other_libs)
+    for lib in libs:
+        result = subprocess.run(
+            [substs["AR"]] + [f.replace("$@", lib) for f in substs["AR_FLAGS"]]
+        )
+        if result.returncode != 0:
+            return result.returncode
+    return 0

build/win32/moz.build

@@ -15,6 +15,17 @@ if CONFIG["ENABLE_TESTS"]:
 
 NO_PGO = True
 
+# See comment about *-windows-gnu targets in config/makefiles/rust.mk
+if CONFIG["CC_TYPE"] == "clang":
+    GeneratedFile(
+        "libgcc.a",
+        "libgcc_eh.a",
+        "libpthread.a",
+        script="dummy_libs.py",
+        flags=["libgcc_eh.a", "libpthread.a"],
+    )
+
+
 if CONFIG["WIN32_REDIST_DIR"] and CONFIG["COMPILE_ENVIRONMENT"]:
     for f in ["MSVC_C_RUNTIME_DLL", "MSVC_CXX_RUNTIME_DLL"]:
         FINAL_TARGET_FILES += ["%%%s/%s" % (CONFIG["WIN32_REDIST_DIR"], CONFIG[f])]

config/makefiles/rust.mk

@@ -330,6 +330,34 @@ ifndef NATIVE_TSAN
 $(TARGET_RECIPES): MOZ_CARGO_WRAP_LDFLAGS:=$(filter-out -fsanitize=cfi% -framework Cocoa -lobjc AudioToolbox ExceptionHandling -fprofile-%,$(LDFLAGS))
 endif # NATIVE_TSAN
 
+# When building programs with sanitizer, rustc links its own runtime, which
+# conflicts with the one that passing -fsanitize=* to the linker would add.
+ifneq (,$(filter -Zsanitizer=%,$(RUSTFLAGS)))
+force-cargo-program-build: MOZ_CARGO_WRAP_LDFLAGS:=$(filter-out -fsanitize=%,$(MOZ_CARGO_WRAP_LDFLAGS))
+endif
+
+# Rustc assumes that *-windows-gnu targets build with mingw-gcc and manually
+# add runtime libraries that don't exist with mingw-clang. We created dummy
+# libraries in $(topobjdir)/build/win32, but that's not enough, because some
+# of the wanted symbols that come from these libraries are available in a
+# different library, that we add manually. We also need to avoid rustc
+# passing -nodefaultlibs to clang so that it adds clang_rt.
+ifeq (WINNT_clang,$(OS_ARCH)_$(CC_TYPE))
+force-cargo-program-build: MOZ_CARGO_WRAP_LDFLAGS+=-L$(topobjdir)/build/win32 -lunwind
+force-cargo-program-build: CARGO_RUSTCFLAGS += -C default-linker-libraries=yes
+endif
+
+# Rustc passes -nodefaultlibs to the linker (clang) on mac, which prevents
+# clang from adding the necessary sanitizer runtimes when building with
+# C/C++ sanitizer but without rust sanitizer.
+ifeq (Darwin,$(OS_ARCH))
+ifeq (,$(filter -Zsanitizer=%,$(RUSTFLAGS)))
+ifneq (,$(filter -fsanitize=%,$(LDFLAGS)))
+force-cargo-program-build: CARGO_RUSTCFLAGS += -C default-linker-libraries=yes
+endif
+endif
+endif
+
 $(HOST_RECIPES): MOZ_CARGO_WRAP_LDFLAGS:=$(HOST_LDFLAGS) $(WRAP_HOST_LINKER_LIBPATHS)
 $(TARGET_RECIPES) $(HOST_RECIPES): MOZ_CARGO_WRAP_HOST_LDFLAGS:=$(HOST_LDFLAGS) $(WRAP_HOST_LINKER_LIBPATHS)
 
@@ -426,7 +454,7 @@ ifdef RUST_PROGRAMS
 
 force-cargo-program-build: $(call resfile,module)
 	$(REPORT_BUILD)
-	$(call CARGO_BUILD) $(addprefix --bin ,$(RUST_CARGO_PROGRAMS)) $(cargo_target_flag) -- $(addprefix -C link-arg=$(CURDIR)/,$(call resfile,module))
+	$(call CARGO_BUILD) $(addprefix --bin ,$(RUST_CARGO_PROGRAMS)) $(cargo_target_flag) -- $(addprefix -C link-arg=$(CURDIR)/,$(call resfile,module)) $(CARGO_RUSTCFLAGS)
 
 $(RUST_PROGRAMS): force-cargo-program-build ;