[sanitizers] fix test failing for -Wunused-command-line-argument

[protze.joachim]

Summary

GotsanRuntimeCheck fails for me, because of unused command-line arguments in combination with the -Werror flag.
This build error blocks the check-all target.

I run into this issue during 12.0 testing, so I think this should also be backported.

[dvyukov]

What is the unused argument? Maybe we should remove the unused argument instead?

[protze.joachim]

FAILED: projects/compiler-rt/lib/tsan/CMakeFiles/GotsanRuntimeCheck 
cd /dev/shm/jprotze/llvm-project/compiler-rt/lib/tsan/go && env "CC=/home/pj416018/sw/UTIL/ccache/bin/clang " IN_TMPDIR=1 SILENT=1 /dev/shm/jprotze/llvm-project/compiler-rt/lib/tsan/go/buildgo.sh
clang-11: error: argument unused during compilation: '-I ../rtl' [-Werror,-Wunused-command-line-argument]
clang-11: error: argument unused during compilation: '-I ../..' [-Werror,-Wunused-command-line-argument]
clang-11: error: argument unused during compilation: '-I ../../sanitizer_common' [-Werror,-Wunused-command-line-argument]
clang-11: error: argument unused during compilation: '-I ../../../include' [-Werror,-Wunused-command-line-argument]

Removing those include directories causes issues in the same compilation step. I'm using ccache-swig as a compiler cache. Probably, this tool breaks the compilation steps further down but does not filter the arguments properly.

[protze.joachim]

How about passing the CMAKE_C_FLAGS into the script? Because of ccache, I use the -Wno-unused-command-line-argument flags anyways.

[dvyukov]

How about passing the CMAKE_C_FLAGS into the script? Because of ccache, I use the -Wno-unused-command-line-argument flags anyways.

This looks fine to me.

[thakis]

This breaks building with PGO: https://logs.chromium.org/logs/chromium/buildbucket/cr-buildbucket.appspot.com/8854980816661584704/+/steps/package_clang/0/stdout?format=raw

FAILED: projects/compiler-rt/lib/tsan/CMakeFiles/GotsanRuntimeCheck 
cd /b/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/lib/tsan/go && env "CC=/b/s/w/ir/cache/builder/src/third_party/llvm-bootstrap-install/bin/clang " "EXTRA_CFLAGS=--gcc-toolchain=/b/s/w/ir/cache/builder/src/third_party/llvm-build-tools/gcc-10.2.0-trusty -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wmissing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wcovered-switch-default -Wdelete-non-virtual-dtor -Wstring-conversion -fdiagnostics-color -ffunction-sections -fdata-sections -fprofile-instr-use=\"/b/s/w/ir/cache/builder/src/third_party/llvm-instrumented/profdata.prof\" -flto=thin -Wall -Wno-unused-parameter" IN_TMPDIR=1 SILENT=1 /b/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/lib/tsan/go/buildgo.sh
error: Could not read profile "/b/s/w/ir/cache/builder/src/third_party/llvm-instrumented/profdata.prof": No such file or directory
1 error generated.

[dvyukov]

Mkay, they I guess we need to revert. Or, Joachim, do you have any ideas for an alternative fix? We could whitelist/blacklist flags from $EXTRA_CFLAGS... I can't think of anything better atm.

[thakis]

Reverted for now in 4b34e0c797e03fa411200f6819ce56d38ce8cc07.

[protze.joachim]

@thakis thanks for reverting the patch. I was offline over the weekend.

The new patch sets -Wno-error=unused-command-line-argument if -Wno-unused-command-line-argument or -Wno-error=unused-command-line-argument is in $CMAKE_C_FLAGS instead of passing CMAKE_C_FLAGS into the script.

[dvyukov]

This is fine with me.

compiler-rt/lib/tsan/CMakeLists.txt

set(TSAN_HEADERS
   rtl/tsan_symbolize.h
   rtl/tsan_sync.h
   rtl/tsan_trace.h
   rtl/tsan_update_shadow_word_inl.h)
 
 set(TSAN_RUNTIME_LIBRARIES)
 add_compiler_rt_component(tsan)
 
+if("${CMAKE_C_FLAGS}" MATCHES "-Wno-(error=)?unused-command-line-argument")
+  set(EXTRA_CFLAGS "-Wno-error=unused-command-line-argument ${EXTRA_CFLAGS}")
+endif()
+
 if(APPLE)
   # Ideally we would check the SDK version for the actual platform we are
   # building for here.  To make our lifes easier we assume the host SDK setup is
   # sane and use the macOS SDK version as a proxy for aligned SDKs.
   find_darwin_sdk_version(macosx_sdk_version "macosx")
   if ("${macosx_sdk_version}" VERSION_LESS 10.12)
     message(FATAL_ERROR "Building the TSan runtime requires at least macOS SDK 10.12 (or aligned SDK on other platforms)")
   endif()
add_compiler_rt_object_libraries(RTTsan_dynamic
     SOURCES ${TSAN_SOURCES} ${TSAN_CXX_SOURCES} ${TSAN_ASM_SOURCES}
     ADDITIONAL_HEADERS ${TSAN_HEADERS}
     CFLAGS ${TSAN_RTL_CFLAGS})
 
   # Build and check Go runtime.
   set(BUILDGO_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/go/buildgo.sh)
   add_custom_target(GotsanRuntimeCheck
     COMMAND env "CC=${CMAKE_C_COMPILER} ${OSX_SYSROOT_FLAG}"
+            EXTRA_CFLAGS=${EXTRA_CFLAGS}
             IN_TMPDIR=1 SILENT=1 ${BUILDGO_SCRIPT}
     DEPENDS tsan ${BUILDGO_SCRIPT}
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/go
     COMMENT "Checking TSan Go runtime..."
     VERBATIM)
   set_target_properties(GotsanRuntimeCheck PROPERTIES FOLDER "Compiler-RT Misc")
 else()
   foreach(arch ${TSAN_SUPPORTED_ARCH})
     if(arch STREQUAL "x86_64")
       add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_amd64.S)
       # Sanity check for Go runtime.
       set(BUILDGO_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/go/buildgo.sh)
       add_custom_target(GotsanRuntimeCheck
         COMMAND env "CC=${CMAKE_C_COMPILER} ${CMAKE_C_COMPILER_ARG1}"
+                EXTRA_CFLAGS=${EXTRA_CFLAGS}
                 IN_TMPDIR=1 SILENT=1 ${BUILDGO_SCRIPT}
         DEPENDS clang_rt.tsan-${arch} ${BUILDGO_SCRIPT}
         WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/go
         COMMENT "Checking TSan Go runtime..."
         VERBATIM)
     elseif(arch STREQUAL "aarch64")
       add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_aarch64.S)
       # Sanity check for Go runtime.
       set(BUILDGO_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/go/buildgo.sh)
       add_custom_target(GotsanRuntimeCheck
   COMMAND env "CC=${CMAKE_C_COMPILER} ${CMAKE_C_COMPILER_ARG1}"
+    EXTRA_CFLAGS=${EXTRA_CFLAGS} 
     IN_TMPDIR=1 SILENT=1 ${BUILDGO_SCRIPT}
   DEPENDS clang_rt.tsan-${arch} ${BUILDGO_SCRIPT}
   WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/go
   COMMENT "Checking TSan Go runtime..."
   VERBATIM)
     elseif(arch MATCHES "powerpc64|powerpc64le")
       add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_ppc64.S)
       # Sanity check for Go runtime.
       set(BUILDGO_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/go/buildgo.sh)
       add_custom_target(GotsanRuntimeCheck
   COMMAND env "CC=${CMAKE_C_COMPILER} ${CMAKE_C_COMPILER_ARG1}"
+    EXTRA_CFLAGS=${EXTRA_CFLAGS} 
     IN_TMPDIR=1 SILENT=1 ${BUILDGO_SCRIPT}
   DEPENDS clang_rt.tsan-${arch} ${BUILDGO_SCRIPT}
   WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/go
   COMMENT "Checking TSan Go runtime..."
   VERBATIM)
     elseif(arch MATCHES "mips64|mips64le")
       add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_mips64.S)
     else()

compiler-rt/lib/tsan/go/buildgo.sh

 
 SRCS="$SRCS $ADD_SRCS"
 
 rm -f $DIR/gotsan.cpp
 for F in $SRCS; do
   cat $F >> $DIR/gotsan.cpp
 done
 
-FLAGS=" -I../rtl -I../.. -I../../sanitizer_common -I../../../include -std=c++14 -Wall -fno-exceptions -fno-rtti -DSANITIZER_GO=1 -DSANITIZER_DEADLOCK_DETECTOR_VERSION=2 $OSCFLAGS $ARCHCFLAGS"
+FLAGS=" -I../rtl -I../.. -I../../sanitizer_common -I../../../include -std=c++14 -Wall -fno-exceptions -fno-rtti -DSANITIZER_GO=1 -DSANITIZER_DEADLOCK_DETECTOR_VERSION=2 $OSCFLAGS $ARCHCFLAGS $EXTRA_CFLAGS"
 DEBUG_FLAGS="$FLAGS -DSANITIZER_DEBUG=1 -g"
 FLAGS="$FLAGS -DSANITIZER_DEBUG=0 -O3 -fomit-frame-pointer"
 if [ "$SUFFIX" = "linux_ppc64le" ]; then
   FLAGS="$FLAGS -mcpu=power8 -fno-function-sections"
 elif [ "$SUFFIX" = "linux_amd64" ]; then
   FLAGS="$FLAGS -msse3"
 fi