| #.rst: |
| # CheckCCompilerFlag |
| # ------------------ |
| # |
| # Check whether the C compiler supports a given flag. |
| # |
| # CHECK_C_COMPILER_FLAG(<flag> <var>) |
| # |
| # :: |
| # |
| # <flag> - the compiler flag |
| # <var> - variable to store the result |
| # Will be created as an internal cache variable. |
| # |
| # This internally calls the check_c_source_compiles macro and sets |
| # CMAKE_REQUIRED_DEFINITIONS to <flag>. See help for |
| # CheckCSourceCompiles for a listing of variables that can otherwise |
| # modify the build. The result only tells that the compiler does not |
| # give an error message when it encounters the flag. If the flag has |
| # any effect or even a specific one is beyond the scope of this module. |
| |
| #============================================================================= |
| # Copyright 2006-2011 Kitware, Inc. |
| # Copyright 2006 Alexander Neundorf <[email protected]> |
| # Copyright 2011 Matthias Kretz <[email protected]> |
| # |
| # Distributed under the OSI-approved BSD License (the "License"); |
| # see accompanying file Copyright.txt for details. |
| # |
| # This software is distributed WITHOUT ANY WARRANTY; without even the |
| # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. |
| # See the License for more information. |
| #============================================================================= |
| # (To distribute this file outside of CMake, substitute the full |
| # License text for the above reference.) |
| |
| include(CheckCSourceCompiles) |
| include(CMakeCheckCompilerFlagCommonPatterns) |
| |
| macro (CHECK_C_COMPILER_FLAG _FLAG _RESULT) |
| set(SAFE_CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS}") |
| set(CMAKE_REQUIRED_DEFINITIONS "${_FLAG}") |
| |
| # Normalize locale during test compilation. |
| set(_CheckCCompilerFlag_LOCALE_VARS LC_ALL LC_MESSAGES LANG) |
| foreach(v ${_CheckCCompilerFlag_LOCALE_VARS}) |
| set(_CheckCCompilerFlag_SAVED_${v} "$ENV{${v}}") |
| set(ENV{${v}} C) |
| endforeach() |
| CHECK_COMPILER_FLAG_COMMON_PATTERNS(_CheckCCompilerFlag_COMMON_PATTERNS) |
| CHECK_C_SOURCE_COMPILES("int main(void) { return 0; }" ${_RESULT} |
| # Some compilers do not fail with a bad flag |
| FAIL_REGEX "command line option .* is valid for .* but not for C" # GNU |
| ${_CheckCCompilerFlag_COMMON_PATTERNS} |
| ) |
| foreach(v ${_CheckCCompilerFlag_LOCALE_VARS}) |
| set(ENV{${v}} ${_CheckCCompilerFlag_SAVED_${v}}) |
| unset(_CheckCCompilerFlag_SAVED_${v}) |
| endforeach() |
| unset(_CheckCCompilerFlag_LOCALE_VARS) |
| unset(_CheckCCompilerFlag_COMMON_PATTERNS) |
| |
| set (CMAKE_REQUIRED_DEFINITIONS "${SAFE_CMAKE_REQUIRED_DEFINITIONS}") |
| endmacro () |
