CMake/Modules/CMakeDetermineCCompiler.cmake

180 lines
6.5 KiB
CMake

# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
# determine the compiler to use for C programs
# NOTE, a generator may set CMAKE_C_COMPILER before
# loading this file to force a compiler.
# use environment variable CC first if defined by user, next use
# the cmake variable CMAKE_GENERATOR_CC which can be defined by a generator
# as a default compiler
# If the internal cmake variable _CMAKE_TOOLCHAIN_PREFIX is set, this is used
# as prefix for the tools (e.g. arm-elf-gcc, arm-elf-ar etc.). This works
# currently with the GNU crosscompilers.
#
# Sets the following variables:
# CMAKE_C_COMPILER
# CMAKE_AR
# CMAKE_RANLIB
# CMAKE_COMPILER_IS_GNUCC
#
# If not already set before, it also sets
# _CMAKE_TOOLCHAIN_PREFIX
include(${CMAKE_ROOT}/Modules/CMakeDetermineCompiler.cmake)
# Load system-specific compiler preferences for this language.
include(Platform/${CMAKE_SYSTEM_NAME}-Determine-C OPTIONAL)
include(Platform/${CMAKE_SYSTEM_NAME}-C OPTIONAL)
if(NOT CMAKE_C_COMPILER_NAMES)
set(CMAKE_C_COMPILER_NAMES cc)
endif()
if(${CMAKE_GENERATOR} MATCHES "Visual Studio")
elseif("${CMAKE_GENERATOR}" MATCHES "Xcode")
set(CMAKE_C_COMPILER_XCODE_TYPE sourcecode.c.c)
_cmake_find_compiler_path(C)
else()
if(NOT CMAKE_C_COMPILER)
set(CMAKE_C_COMPILER_INIT NOTFOUND)
# prefer the environment variable CC
if(NOT $ENV{CC} STREQUAL "")
get_filename_component(CMAKE_C_COMPILER_INIT $ENV{CC} PROGRAM PROGRAM_ARGS CMAKE_C_FLAGS_ENV_INIT)
if(CMAKE_C_FLAGS_ENV_INIT)
set(CMAKE_C_COMPILER_ARG1 "${CMAKE_C_FLAGS_ENV_INIT}" CACHE STRING "First argument to C compiler")
endif()
if(NOT EXISTS ${CMAKE_C_COMPILER_INIT})
message(FATAL_ERROR "Could not find compiler set in environment variable CC:\n$ENV{CC}.")
endif()
endif()
# next try prefer the compiler specified by the generator
if(CMAKE_GENERATOR_CC)
if(NOT CMAKE_C_COMPILER_INIT)
set(CMAKE_C_COMPILER_INIT ${CMAKE_GENERATOR_CC})
endif()
endif()
# finally list compilers to try
if(NOT CMAKE_C_COMPILER_INIT)
set(CMAKE_C_COMPILER_LIST ${_CMAKE_TOOLCHAIN_PREFIX}cc ${_CMAKE_TOOLCHAIN_PREFIX}gcc cl bcc xlc clang)
endif()
_cmake_find_compiler(C)
else()
_cmake_find_compiler_path(C)
endif()
mark_as_advanced(CMAKE_C_COMPILER)
# Each entry in this list is a set of extra flags to try
# adding to the compile line to see if it helps produce
# a valid identification file.
set(CMAKE_C_COMPILER_ID_TEST_FLAGS_FIRST)
set(CMAKE_C_COMPILER_ID_TEST_FLAGS
# Try compiling to an object file only.
"-c"
# Try enabling ANSI mode on HP.
"-Aa"
# Try compiling K&R-compatible code (needed by Bruce C Compiler).
"-D__CLASSIC_C__"
)
endif()
# Build a small source file to identify the compiler.
if(NOT CMAKE_C_COMPILER_ID_RUN)
set(CMAKE_C_COMPILER_ID_RUN 1)
# Try to identify the compiler.
set(CMAKE_C_COMPILER_ID)
set(CMAKE_C_PLATFORM_ID)
file(READ ${CMAKE_ROOT}/Modules/CMakePlatformId.h.in
CMAKE_C_COMPILER_ID_PLATFORM_CONTENT)
# The IAR compiler produces weird output.
# See https://gitlab.kitware.com/cmake/cmake/issues/10176#note_153591
list(APPEND CMAKE_C_COMPILER_ID_VENDORS IAR)
set(CMAKE_C_COMPILER_ID_VENDOR_FLAGS_IAR )
set(CMAKE_C_COMPILER_ID_VENDOR_REGEX_IAR "IAR .+ Compiler")
# Match the link line from xcodebuild output of the form
# Ld ...
# ...
# /path/to/cc ...CompilerIdC/...
# to extract the compiler front-end for the language.
set(CMAKE_C_COMPILER_ID_TOOL_MATCH_REGEX "\nLd[^\n]*(\n[ \t]+[^\n]*)*\n[ \t]+([^ \t\r\n]+)[^\r\n]*-o[^\r\n]*CompilerIdC/(\\./)?(CompilerIdC.xctest/)?CompilerIdC[ \t\n\\\"]")
set(CMAKE_C_COMPILER_ID_TOOL_MATCH_INDEX 2)
include(${CMAKE_ROOT}/Modules/CMakeDetermineCompilerId.cmake)
CMAKE_DETERMINE_COMPILER_ID(C CFLAGS CMakeCCompilerId.c)
# Set old compiler and platform id variables.
if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
set(CMAKE_COMPILER_IS_GNUCC 1)
endif()
if(CMAKE_C_PLATFORM_ID MATCHES "MinGW")
set(CMAKE_COMPILER_IS_MINGW 1)
elseif(CMAKE_C_PLATFORM_ID MATCHES "Cygwin")
set(CMAKE_COMPILER_IS_CYGWIN 1)
endif()
endif()
if (NOT _CMAKE_TOOLCHAIN_LOCATION)
get_filename_component(_CMAKE_TOOLCHAIN_LOCATION "${CMAKE_C_COMPILER}" PATH)
endif ()
# If we have a gcc cross compiler, they have usually some prefix, like
# e.g. powerpc-linux-gcc, arm-elf-gcc or i586-mingw32msvc-gcc, optionally
# with a 3-component version number at the end (e.g. arm-eabi-gcc-4.5.2).
# The other tools of the toolchain usually have the same prefix
# NAME_WE cannot be used since then this test will fail for names like
# "arm-unknown-nto-qnx6.3.0-gcc.exe", where BASENAME would be
# "arm-unknown-nto-qnx6" instead of the correct "arm-unknown-nto-qnx6.3.0-"
if (CMAKE_CROSSCOMPILING AND NOT _CMAKE_TOOLCHAIN_PREFIX)
if(CMAKE_C_COMPILER_ID MATCHES "GNU" OR CMAKE_C_COMPILER_ID MATCHES "Clang")
get_filename_component(COMPILER_BASENAME "${CMAKE_C_COMPILER}" NAME)
if (COMPILER_BASENAME MATCHES "^(.+-)(clang|g?cc)(-[0-9]+\\.[0-9]+\\.[0-9]+)?(\\.exe)?$")
set(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_MATCH_1})
elseif(CMAKE_C_COMPILER_ID MATCHES "Clang")
if(CMAKE_C_COMPILER_TARGET)
set(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_C_COMPILER_TARGET}-)
endif()
elseif(COMPILER_BASENAME MATCHES "qcc(\\.exe)?$")
if(CMAKE_C_COMPILER_TARGET MATCHES "gcc_nto([^_le]+)(le)?")
set(_CMAKE_TOOLCHAIN_PREFIX nto${CMAKE_MATCH_1}-)
endif()
endif ()
# if "llvm-" is part of the prefix, remove it, since llvm doesn't have its own binutils
# but uses the regular ar, objcopy, etc. (instead of llvm-objcopy etc.)
if ("${_CMAKE_TOOLCHAIN_PREFIX}" MATCHES "(.+-)?llvm-$")
set(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_MATCH_1})
endif ()
elseif(CMAKE_C_COMPILER_ID MATCHES "TI")
# TI compilers are named e.g. cl6x, cl470 or armcl.exe
get_filename_component(COMPILER_BASENAME "${CMAKE_C_COMPILER}" NAME)
if (COMPILER_BASENAME MATCHES "^(.+)?cl([^.]+)?(\\.exe)?$")
set(_CMAKE_TOOLCHAIN_PREFIX "${CMAKE_MATCH_1}")
set(_CMAKE_TOOLCHAIN_SUFFIX "${CMAKE_MATCH_2}")
endif ()
endif()
endif ()
include(CMakeFindBinUtils)
if(MSVC_C_ARCHITECTURE_ID)
set(SET_MSVC_C_ARCHITECTURE_ID
"set(MSVC_C_ARCHITECTURE_ID ${MSVC_C_ARCHITECTURE_ID})")
endif()
# configure variables set in this file for fast reload later on
configure_file(${CMAKE_ROOT}/Modules/CMakeCCompiler.cmake.in
${CMAKE_PLATFORM_INFO_DIR}/CMakeCCompiler.cmake
@ONLY
)
set(CMAKE_C_COMPILER_ENV_VAR "CC")