diff options
author | Sergey Sharybin <sergey.vfx@gmail.com> | 2016-05-22 14:41:55 +0300 |
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committer | Sergey Sharybin <sergey.vfx@gmail.com> | 2016-05-22 14:48:52 +0300 |
commit | 6115267a845a49bdf9a5d4c701fcf5b995fc499a (patch) | |
tree | 976e286d4ababadaaaa94775ea8d9ccc9b699ca2 /build_files/cmake | |
parent | e21af38f69577229c93cf46aab655384ee864948 (diff) |
CMake: Solve compilation error with pre-compiled libraries and new GCC-6
Since version 6 G++ switched to C++11 by default, which breaks some logic
around WITH_CXX11 checks in out CMake files, leading to compilation errors.
This is easy to solve by explicitly enabling older C++ standard when C++11
was not explicitly enabled by CMake options.
However, G++-6 will also use new ABI by default even if older standard was
specified in the compiler options. This is being addressed by a special
define flag.
This tricks made it possible to use new G++-6 without need to recompile
any of pre-compiled libraries.
However, this might break compilation with existing system libraries, which
might already be using new ABI. We can't address this automatically, so
now we simply default WITH_C11 and WITH_CXX11 options to whatever defaults
of the current compiler are. This means, for G++-6 we'll set WITH_CXX11 to
truth. This should make linking with system libraries working just fine,
but to make pre-compiled libraries we still might need to disable CXX11.
This should work fine work for a new environments with G++-6 and install_deps
script run from scratch there, because C++ standard will be the same for
both Blender dependencies and Blender itself.
Diffstat (limited to 'build_files/cmake')
-rw-r--r-- | build_files/cmake/macros.cmake | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/build_files/cmake/macros.cmake b/build_files/cmake/macros.cmake index 239371c227c..08d26e55ed4 100644 --- a/build_files/cmake/macros.cmake +++ b/build_files/cmake/macros.cmake @@ -803,7 +803,15 @@ macro(TEST_UNORDERED_MAP_SUPPORT) # UNORDERED_MAP_NAMESPACE, namespace for unordered_map, if found include(CheckIncludeFileCXX) - CHECK_INCLUDE_FILE_CXX("unordered_map" HAVE_STD_UNORDERED_MAP_HEADER) + + # Workaround for newer GCC (6.x+) where C++11 was enabled by default, which lead us + # to a situation when there is <unordered_map> include but which can't be used uless + # C++11 is enabled. + if(CMAKE_COMPILER_IS_GNUCC AND (NOT "${CMAKE_C_COMPILER_VERSION}" VERSION_LESS "6.0") AND (NOT WITH_CXX11)) + set(HAVE_STD_UNORDERED_MAP_HEADER False) + else() + CHECK_INCLUDE_FILE_CXX("unordered_map" HAVE_STD_UNORDERED_MAP_HEADER) + endif() if(HAVE_STD_UNORDERED_MAP_HEADER) # Even so we've found unordered_map header file it doesn't # mean unordered_map and unordered_set will be declared in |