• chuck cranor's avatar
    Compute implicit include directories from compiler output · 5990ecb7
    chuck cranor authored
     - CMakeParseImplicitIncludeInfo.cmake: new parser that extracts the
       compiler's include path from verbose output.  If the parser cannot
       parse the output, we fall back to the old behavior.  On osx we skip
       over framework directories (handled elsewhere).
    
     - CMakeDetermineCompilerABI.cmake:
         - use verbose flag in try_compile for ${src}
         - use new cmake_parse_implicit_include_info() to attempt extract
           implicit include directory path and if successful set
            CMAKE_${LANG}_IMPLICIT_INCLUDE_DIRECTORIES
    
     - CMakeCCompiler.cmake.in and CMakeCXXCompiler.cmake.in - preserve
       CMAKE_${LANG}_IMPLICIT_INCLUDE_DIRECTORIES value between runs in
       the same way CMAKE_${LANG}_IMPLICIT_LINK_DIRECTORIES is preserved
    
     - Tests/RunCMake/ParseImplicitIncludeInfo: tests for parse
       based on the older Tests/CMakeTests/ImplicitLinkInfoTest.cmake.in.
       The test runs a set of verbose compiler outputs collected from
       various machines through the parser and checks the results.  New
       compiler files can be added by dropping input/output files in the
       ParseImplicitIncludeInfo/data subdirectory and then adding the new set
       of files to the ${targets} list in ParseImplicitIncludeInfo.cmake.
       There is a helper CMakeLists.txt in ParseImplicitIncludeInfo/data
       that can help with the generation of test input files.
       NOTE: the standard cmake pre-commit hook rejects verbose compiler
       output with trailing spaces... you have to manually edit them out.
       This shouldn't impact the test.
    
    Note that both the parser and the test code can use CMAKE_${LANG}_COMPILER_*
    variables such as ${CMAKE_CXX_COMPILER_ID} to decide how to parse
    verbose compiler output.  For the test code, this requires us to
    save the variables values in the test input files.
    
    Fixes: #16291
    5990ecb7