WCDH: Make the header -Wundef safe for the C language.

The __STDC_VERSION__ macro may be defined or not depending on the
implementation dialect of C.  Test that it is defined before testing
its value.

The CXX tests do not need such a change because they define __cplusplus
in all dialects.
This commit is contained in:
Stephen Kelly 2014-11-24 21:47:48 +01:00
parent 598a316154
commit d0af0faefb
4 changed files with 18 additions and 4 deletions

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@ -1,9 +1,9 @@
set(_cmake_oldestSupported "((__clang_major__ * 100) + __clang_minor__) >= 304")
set(Clang_C11 "${_cmake_oldestSupported} && __STDC_VERSION__ >= 201112L")
set(Clang_C11 "${_cmake_oldestSupported} && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L")
set(_cmake_feature_test_c_static_assert "${Clang_C11}")
set(Clang_C99 "${_cmake_oldestSupported} && __STDC_VERSION__ >= 199901L")
set(Clang_C99 "${_cmake_oldestSupported} && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L")
set(_cmake_feature_test_c_restrict "${Clang_C99}")
set(_cmake_feature_test_c_variadic_macros "${Clang_C99}")

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@ -1,10 +1,10 @@
set(_cmake_oldestSupported "(__GNUC__ * 100 + __GNUC_MINOR__) >= 407")
set(GNU46_C11 "${_cmake_oldestSupported} && __STDC_VERSION__ >= 201112L")
set(GNU46_C11 "${_cmake_oldestSupported} && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L")
set(_cmake_feature_test_c_static_assert "${GNU46_C11}")
# Since 4.4 at least:
set(GNU44_C99 "${_cmake_oldestSupported} && __STDC_VERSION__ >= 199901L")
set(GNU44_C99 "${_cmake_oldestSupported} && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L")
set(_cmake_feature_test_c_restrict "${GNU44_C99}")
set(_cmake_feature_test_c_variadic_macros "${GNU44_C99}")

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@ -63,6 +63,13 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL GNU
list(APPEND false_defs EXPECTED_COMPILER_CXX_VARIADIC_TEMPLATES)
endif()
if (CMAKE_C_COMPILER_ID STREQUAL GNU
OR CMAKE_C_COMPILER_ID STREQUAL Clang)
add_executable(C_undefined c_undefined.c)
set_property(TARGET C_undefined PROPERTY CXX_STANDARD 90)
target_compile_options(C_undefined PRIVATE -Werror=undef)
endif()
add_executable(WriteCompilerDetectionHeader main.cpp)
set_property(TARGET WriteCompilerDetectionHeader PROPERTY CXX_STANDARD 98)
set_defines(WriteCompilerDetectionHeader "${true_defs}" "${false_defs}")

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@ -0,0 +1,7 @@
#include "test_compiler_detection.h"
int main()
{
return 0;
}