CMake/Modules/CMakeTestCXXCompiler.cmake
Brad King 86578eccf2 Simplify CMake per-source license notices
Per-source copyright/license notice headers that spell out copyright holder
names and years are hard to maintain and often out-of-date or plain wrong.
Precise contributor information is already maintained automatically by the
version control tool.  Ultimately it is the receiver of a file who is
responsible for determining its licensing status, and per-source notices are
merely a convenience.  Therefore it is simpler and more accurate for
each source to have a generic notice of the license name and references to
more detailed information on copyright holders and full license terms.

Our `Copyright.txt` file now contains a list of Contributors whose names
appeared source-level copyright notices.  It also references version control
history for more precise information.  Therefore we no longer need to spell
out the list of Contributors in each source file notice.

Replace CMake per-source copyright/license notice headers with a short
description of the license and links to `Copyright.txt` and online information
available from "https://cmake.org/licensing".  The online URL also handles
cases of modules being copied out of our source into other projects, so we
can drop our notices about replacing links with full license text.

Run the `Utilities/Scripts/filter-notices.bash` script to perform the majority
of the replacements mechanically.  Manually fix up shebang lines and trailing
newlines in a few files.  Manually update the notices in a few files that the
script does not handle.
2016-09-27 15:14:44 -04:00

80 lines
3.0 KiB
CMake

# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
if(CMAKE_CXX_COMPILER_FORCED)
# The compiler configuration was forced by the user.
# Assume the user has configured all compiler information.
set(CMAKE_CXX_COMPILER_WORKS TRUE)
return()
endif()
include(CMakeTestCompilerCommon)
# Remove any cached result from an older CMake version.
# We now store this in CMakeCXXCompiler.cmake.
unset(CMAKE_CXX_COMPILER_WORKS CACHE)
# This file is used by EnableLanguage in cmGlobalGenerator to
# determine that that selected C++ compiler can actually compile
# and link the most basic of programs. If not, a fatal error
# is set and cmake stops processing commands and will not generate
# any makefiles or projects.
if(NOT CMAKE_CXX_COMPILER_WORKS)
PrintTestCompilerStatus("CXX" "")
file(WRITE ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/testCXXCompiler.cxx
"#ifndef __cplusplus\n"
"# error \"The CMAKE_CXX_COMPILER is set to a C compiler\"\n"
"#endif\n"
"int main(){return 0;}\n")
try_compile(CMAKE_CXX_COMPILER_WORKS ${CMAKE_BINARY_DIR}
${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/testCXXCompiler.cxx
OUTPUT_VARIABLE __CMAKE_CXX_COMPILER_OUTPUT)
# Move result from cache to normal variable.
set(CMAKE_CXX_COMPILER_WORKS ${CMAKE_CXX_COMPILER_WORKS})
unset(CMAKE_CXX_COMPILER_WORKS CACHE)
set(CXX_TEST_WAS_RUN 1)
endif()
if(NOT CMAKE_CXX_COMPILER_WORKS)
PrintTestCompilerStatus("CXX" " -- broken")
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Determining if the CXX compiler works failed with "
"the following output:\n${__CMAKE_CXX_COMPILER_OUTPUT}\n\n")
message(FATAL_ERROR "The C++ compiler \"${CMAKE_CXX_COMPILER}\" "
"is not able to compile a simple test program.\nIt fails "
"with the following output:\n ${__CMAKE_CXX_COMPILER_OUTPUT}\n\n"
"CMake will not be able to correctly generate this project.")
else()
if(CXX_TEST_WAS_RUN)
PrintTestCompilerStatus("CXX" " -- works")
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
"Determining if the CXX compiler works passed with "
"the following output:\n${__CMAKE_CXX_COMPILER_OUTPUT}\n\n")
endif()
# Try to identify the ABI and configure it into CMakeCXXCompiler.cmake
include(${CMAKE_ROOT}/Modules/CMakeDetermineCompilerABI.cmake)
CMAKE_DETERMINE_COMPILER_ABI(CXX ${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp)
# Try to identify the compiler features
include(${CMAKE_ROOT}/Modules/CMakeDetermineCompileFeatures.cmake)
CMAKE_DETERMINE_COMPILE_FEATURES(CXX)
# Re-configure to save learned information.
configure_file(
${CMAKE_ROOT}/Modules/CMakeCXXCompiler.cmake.in
${CMAKE_PLATFORM_INFO_DIR}/CMakeCXXCompiler.cmake
@ONLY
)
include(${CMAKE_PLATFORM_INFO_DIR}/CMakeCXXCompiler.cmake)
if(CMAKE_CXX_SIZEOF_DATA_PTR)
foreach(f ${CMAKE_CXX_ABI_FILES})
include(${f})
endforeach()
unset(CMAKE_CXX_ABI_FILES)
endif()
endif()
unset(__CMAKE_CXX_COMPILER_OUTPUT)