Silence warning for unrecognised "-std=c99" warning on MSVC

[compnerd]

lib/builtins/CMakeLists.txt

369 ↗

(On Diff #37232)

How about making this more similar to the other flags checks? We could then just do the append_if

[angelsl]

CMake variable expansion @_@

[compnerd]

This seems to filter it even on Darwin? At least when I tested it, it did. Im not sure what is causing that.

[angelsl]

Nothing to do with my change, Darwin/Apple doesn't even go through it; there's the if (APPLE) branch above it.

[samsonov]

Instead of special-casing on MSVC, can you add check_c_compiler_flag(-std=c99 COMPILER_RT_HAS_STD_C99_FLAG) to cmake/config-ix.cmake, and properly use it here?

[angelsl]

Use LLVM-style compiler flag checks

[angelsl]

Append the flag outside the loop (otherwise we get it twice, thrice, etc)

[angelsl]

I didn't notice -std=c++11 was considered a codegen option.

[samsonov]

LGTM

[angelsl]

Please help me commit this, thanks!

[angelsl]

Would appreciate it if someone commited this.

compiler-rt/trunk/cmake/config-ix.cmake

 check_cxx_compiler_flag(-fvisibility=hidden  COMPILER_RT_HAS_FVISIBILITY_HIDDEN_FLAG)
 check_cxx_compiler_flag(-fno-rtti            COMPILER_RT_HAS_FNO_RTTI_FLAG)
 check_cxx_compiler_flag(-ffreestanding       COMPILER_RT_HAS_FFREESTANDING_FLAG)
 check_cxx_compiler_flag("-Werror -fno-function-sections" COMPILER_RT_HAS_FNO_FUNCTION_SECTIONS_FLAG)
 check_cxx_compiler_flag(-std=c++11           COMPILER_RT_HAS_STD_CXX11_FLAG)
 check_cxx_compiler_flag(-ftls-model=initial-exec COMPILER_RT_HAS_FTLS_MODEL_INITIAL_EXEC)
 check_cxx_compiler_flag(-fno-lto             COMPILER_RT_HAS_FNO_LTO_FLAG)
 check_cxx_compiler_flag(-msse3               COMPILER_RT_HAS_MSSE3_FLAG)
+check_c_compiler_flag(-std=c99 COMPILER_RT_HAS_STD_C99_FLAG)
 
 check_cxx_compiler_flag(/GR COMPILER_RT_HAS_GR_FLAG)
 check_cxx_compiler_flag(/GS COMPILER_RT_HAS_GS_FLAG)
 check_cxx_compiler_flag(/MT COMPILER_RT_HAS_MT_FLAG)
 check_cxx_compiler_flag(/Oy COMPILER_RT_HAS_Oy_FLAG)
 
 # Debug info flags.
 check_cxx_compiler_flag(-gline-tables-only COMPILER_RT_HAS_GLINE_TABLES_ONLY_FLAG)

compiler-rt/trunk/lib/builtins/CMakeLists.txt

 
 add_custom_target(builtins)
 
 if (APPLE)
   add_subdirectory(Darwin-excludes)
   add_subdirectory(macho_embedded)
   darwin_add_builtin_libraries(${BUILTIN_SUPPORTED_OS})
 elseif (NOT WIN32 OR MINGW)
+  append_string_if(COMPILER_RT_HAS_STD_C99_FLAG -std=c99 maybe_stdc99)
+
   foreach (arch ${BUILTIN_SUPPORTED_ARCH})
     if (CAN_TARGET_${arch})
       # Filter out generic versions of routines that are re-implemented in
       # architecture specific manner.  This prevents multiple definitions of the
       # same symbols, making the symbol selection non-deterministic.
       foreach (_file ${${arch}_SOURCES})
         if (${_file} MATCHES ${arch}/*)
           get_filename_component(_name ${_file} NAME)
           string(REPLACE ".S" ".c" _cname "${_name}")
           list(REMOVE_ITEM ${arch}_SOURCES ${_cname})
         endif ()
       endforeach ()
 
       add_compiler_rt_runtime(clang_rt.builtins
                               STATIC
                               ARCHS ${arch}
                               SOURCES ${${arch}_SOURCES}
-                              CFLAGS "-std=c99"
+                              CFLAGS ${maybe_stdc99}
                               PARENT_TARGET builtins)
     endif ()
   endforeach ()
 endif ()
 
 add_dependencies(compiler-rt builtins)