2 #=============================================================================
3 # Copyright 2002-2009 Kitware, Inc.
5 # Distributed under the OSI-approved BSD License (the "License");
6 # see accompanying file Copyright.txt for details.
8 # This software is distributed WITHOUT ANY WARRANTY; without even the
9 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
10 # See the License for more information.
11 #=============================================================================
12 # (To distribute this file outside of CMake, substitute the full
13 # License text for the above reference.)
15 # determine the compiler to use for C programs
16 # NOTE, a generator may set CMAKE_C_COMPILER before
17 # loading this file to force a compiler.
18 # use environment variable CC first if defined by user, next use
19 # the cmake variable CMAKE_GENERATOR_CC which can be defined by a generator
20 # as a default compiler
21 # If the internal cmake variable _CMAKE_TOOLCHAIN_PREFIX is set, this is used
22 # as prefix for the tools (e.g. arm-elf-gcc, arm-elf-ar etc.). This works
23 # currently with the GNU crosscompilers.
25 # Sets the following variables:
29 # CMAKE_COMPILER_IS_GNUCC
31 # If not already set before, it also sets
32 # _CMAKE_TOOLCHAIN_PREFIX
34 IF(NOT CMAKE_C_COMPILER)
35 SET(CMAKE_C_COMPILER_INIT NOTFOUND)
37 # prefer the environment variable CC
38 IF($ENV{CC} MATCHES ".+")
39 GET_FILENAME_COMPONENT(CMAKE_C_COMPILER_INIT $ENV{CC} PROGRAM PROGRAM_ARGS CMAKE_C_FLAGS_ENV_INIT)
40 IF(CMAKE_C_FLAGS_ENV_INIT)
41 SET(CMAKE_C_COMPILER_ARG1 "${CMAKE_C_FLAGS_ENV_INIT}" CACHE STRING "First argument to C compiler")
42 ENDIF(CMAKE_C_FLAGS_ENV_INIT)
43 IF(NOT EXISTS ${CMAKE_C_COMPILER_INIT})
44 MESSAGE(FATAL_ERROR "Could not find compiler set in environment variable CC:\n$ENV{CC}.")
45 ENDIF(NOT EXISTS ${CMAKE_C_COMPILER_INIT})
46 ENDIF($ENV{CC} MATCHES ".+")
48 # next try prefer the compiler specified by the generator
49 IF(CMAKE_GENERATOR_CC)
50 IF(NOT CMAKE_C_COMPILER_INIT)
51 SET(CMAKE_C_COMPILER_INIT ${CMAKE_GENERATOR_CC})
52 ENDIF(NOT CMAKE_C_COMPILER_INIT)
53 ENDIF(CMAKE_GENERATOR_CC)
55 # finally list compilers to try
56 IF(CMAKE_C_COMPILER_INIT)
57 SET(CMAKE_C_COMPILER_LIST ${CMAKE_C_COMPILER_INIT})
58 ELSE(CMAKE_C_COMPILER_INIT)
59 SET(CMAKE_C_COMPILER_LIST ${_CMAKE_TOOLCHAIN_PREFIX}gcc ${_CMAKE_TOOLCHAIN_PREFIX}cc cl bcc xlc)
60 ENDIF(CMAKE_C_COMPILER_INIT)
63 IF (_CMAKE_USER_CXX_COMPILER_PATH)
64 FIND_PROGRAM(CMAKE_C_COMPILER NAMES ${CMAKE_C_COMPILER_LIST} PATHS ${_CMAKE_USER_CXX_COMPILER_PATH} DOC "C compiler" NO_DEFAULT_PATH)
65 ENDIF (_CMAKE_USER_CXX_COMPILER_PATH)
66 FIND_PROGRAM(CMAKE_C_COMPILER NAMES ${CMAKE_C_COMPILER_LIST} DOC "C compiler")
68 IF(CMAKE_C_COMPILER_INIT AND NOT CMAKE_C_COMPILER)
69 SET(CMAKE_C_COMPILER "${CMAKE_C_COMPILER_INIT}" CACHE FILEPATH "C compiler" FORCE)
70 ENDIF(CMAKE_C_COMPILER_INIT AND NOT CMAKE_C_COMPILER)
71 ELSE(NOT CMAKE_C_COMPILER)
73 # we only get here if CMAKE_C_COMPILER was specified using -D or a pre-made CMakeCache.txt
74 # (e.g. via ctest) or set in CMAKE_TOOLCHAIN_FILE
75 # if CMAKE_C_COMPILER is a list of length 2, use the first item as
76 # CMAKE_C_COMPILER and the 2nd one as CMAKE_C_COMPILER_ARG1
78 LIST(LENGTH CMAKE_C_COMPILER _CMAKE_C_COMPILER_LIST_LENGTH)
79 IF("${_CMAKE_C_COMPILER_LIST_LENGTH}" EQUAL 2)
80 LIST(GET CMAKE_C_COMPILER 1 CMAKE_C_COMPILER_ARG1)
81 LIST(GET CMAKE_C_COMPILER 0 CMAKE_C_COMPILER)
82 ENDIF("${_CMAKE_C_COMPILER_LIST_LENGTH}" EQUAL 2)
84 # if a compiler was specified by the user but without path,
85 # now try to find it with the full path
86 # if it is found, force it into the cache,
87 # if not, don't overwrite the setting (which was given by the user) with "NOTFOUND"
88 # if the C compiler already had a path, reuse it for searching the CXX compiler
89 GET_FILENAME_COMPONENT(_CMAKE_USER_C_COMPILER_PATH "${CMAKE_C_COMPILER}" PATH)
90 IF(NOT _CMAKE_USER_C_COMPILER_PATH)
91 FIND_PROGRAM(CMAKE_C_COMPILER_WITH_PATH NAMES ${CMAKE_C_COMPILER})
92 MARK_AS_ADVANCED(CMAKE_C_COMPILER_WITH_PATH)
93 IF(CMAKE_C_COMPILER_WITH_PATH)
94 SET(CMAKE_C_COMPILER ${CMAKE_C_COMPILER_WITH_PATH} CACHE STRING "C compiler" FORCE)
95 ENDIF(CMAKE_C_COMPILER_WITH_PATH)
96 ENDIF(NOT _CMAKE_USER_C_COMPILER_PATH)
97 ENDIF(NOT CMAKE_C_COMPILER)
98 MARK_AS_ADVANCED(CMAKE_C_COMPILER)
100 IF (NOT _CMAKE_TOOLCHAIN_LOCATION)
101 GET_FILENAME_COMPONENT(_CMAKE_TOOLCHAIN_LOCATION "${CMAKE_C_COMPILER}" PATH)
102 ENDIF (NOT _CMAKE_TOOLCHAIN_LOCATION)
104 # Build a small source file to identify the compiler.
105 IF(${CMAKE_GENERATOR} MATCHES "Visual Studio")
106 SET(CMAKE_C_COMPILER_ID_RUN 1)
107 SET(CMAKE_C_PLATFORM_ID "Windows")
108 SET(CMAKE_C_COMPILER_ID "MSVC")
109 ENDIF(${CMAKE_GENERATOR} MATCHES "Visual Studio")
111 IF(NOT CMAKE_C_COMPILER_ID_RUN)
112 SET(CMAKE_C_COMPILER_ID_RUN 1)
114 # Each entry in this list is a set of extra flags to try
115 # adding to the compile line to see if it helps produce
116 # a valid identification file.
117 SET(CMAKE_C_COMPILER_ID_TEST_FLAGS
118 # Try compiling to an object file only.
121 # Try enabling ANSI mode on HP.
125 # Try to identify the compiler.
126 SET(CMAKE_C_COMPILER_ID)
127 FILE(READ ${CMAKE_ROOT}/Modules/CMakePlatformId.h.in
128 CMAKE_C_COMPILER_ID_PLATFORM_CONTENT)
129 INCLUDE(${CMAKE_ROOT}/Modules/CMakeDetermineCompilerId.cmake)
130 CMAKE_DETERMINE_COMPILER_ID(C CFLAGS CMakeCCompilerId.c)
132 # Set old compiler and platform id variables.
133 IF("${CMAKE_C_COMPILER_ID}" MATCHES "GNU")
134 SET(CMAKE_COMPILER_IS_GNUCC 1)
135 ENDIF("${CMAKE_C_COMPILER_ID}" MATCHES "GNU")
136 IF("${CMAKE_C_PLATFORM_ID}" MATCHES "MinGW")
137 SET(CMAKE_COMPILER_IS_MINGW 1)
138 ELSEIF("${CMAKE_C_PLATFORM_ID}" MATCHES "Cygwin")
139 SET(CMAKE_COMPILER_IS_CYGWIN 1)
140 ENDIF("${CMAKE_C_PLATFORM_ID}" MATCHES "MinGW")
141 ENDIF(NOT CMAKE_C_COMPILER_ID_RUN)
143 # If we have a gcc cross compiler, they have usually some prefix, like
144 # e.g. powerpc-linux-gcc, arm-elf-gcc or i586-mingw32msvc-gcc, optionally
145 # with a 3-component version number at the end (e.g. arm-eabi-gcc-4.5.2).
146 # The other tools of the toolchain usually have the same prefix
147 # NAME_WE cannot be used since then this test will fail for names lile
148 # "arm-unknown-nto-qnx6.3.0-gcc.exe", where BASENAME would be
149 # "arm-unknown-nto-qnx6" instead of the correct "arm-unknown-nto-qnx6.3.0-"
150 IF (CMAKE_CROSSCOMPILING
151 AND "${CMAKE_C_COMPILER_ID}" MATCHES "GNU"
152 AND NOT _CMAKE_TOOLCHAIN_PREFIX)
153 GET_FILENAME_COMPONENT(COMPILER_BASENAME "${CMAKE_C_COMPILER}" NAME)
154 IF (COMPILER_BASENAME MATCHES "^(.+-)g?cc(-[0-9]+\\.[0-9]+\\.[0-9]+)?(\\.exe)?$")
155 SET(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_MATCH_1})
156 ENDIF (COMPILER_BASENAME MATCHES "^(.+-)g?cc(-[0-9]+\\.[0-9]+\\.[0-9]+)?(\\.exe)?$")
158 # if "llvm-" is part of the prefix, remove it, since llvm doesn't have its own binutils
159 # but uses the regular ar, objcopy, etc. (instead of llvm-objcopy etc.)
160 IF ("${_CMAKE_TOOLCHAIN_PREFIX}" MATCHES "(.+-)?llvm-$")
161 SET(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_MATCH_1})
162 ENDIF ("${_CMAKE_TOOLCHAIN_PREFIX}" MATCHES "(.+-)?llvm-$")
164 ENDIF (CMAKE_CROSSCOMPILING
165 AND "${CMAKE_C_COMPILER_ID}" MATCHES "GNU"
166 AND NOT _CMAKE_TOOLCHAIN_PREFIX)
168 INCLUDE(${CMAKE_ROOT}/Modules/CMakeClDeps.cmake)
169 INCLUDE(CMakeFindBinUtils)
170 IF(MSVC_C_ARCHITECTURE_ID)
171 SET(SET_MSVC_C_ARCHITECTURE_ID
172 "SET(MSVC_C_ARCHITECTURE_ID ${MSVC_C_ARCHITECTURE_ID})")
173 ENDIF(MSVC_C_ARCHITECTURE_ID)
174 # configure variables set in this file for fast reload later on
175 CONFIGURE_FILE(${CMAKE_ROOT}/Modules/CMakeCCompiler.cmake.in
176 "${CMAKE_PLATFORM_ROOT_BIN}/CMakeCCompiler.cmake"
177 @ONLY IMMEDIATE # IMMEDIATE must be here for compatibility mode <= 2.0
179 SET(CMAKE_C_COMPILER_ENV_VAR "CC")