CMakeDetermineCCompiler.cmake 6.88 KB
Newer Older
1

2 3 4 5 6 7 8 9 10 11
#=============================================================================
# Copyright 2002-2009 Kitware, Inc.
#
# Distributed under the OSI-approved BSD License (the "License");
# see accompanying file Copyright.txt for details.
#
# This software is distributed WITHOUT ANY WARRANTY; without even the
# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the License for more information.
#=============================================================================
12
# (To distribute this file outside of CMake, substitute the full
13 14
#  License text for the above reference.)

15 16 17
# determine the compiler to use for C programs
# NOTE, a generator may set CMAKE_C_COMPILER before
# loading this file to force a compiler.
18
# use environment variable CC first if defined by user, next use
19 20
# the cmake variable CMAKE_GENERATOR_CC which can be defined by a generator
# as a default compiler
21
# If the internal cmake variable _CMAKE_TOOLCHAIN_PREFIX is set, this is used
22 23 24
# as prefix for the tools (e.g. arm-elf-gcc, arm-elf-ar etc.). This works
# currently with the GNU crosscompilers.
#
25
# Sets the following variables:
26 27 28 29 30 31 32
#   CMAKE_C_COMPILER
#   CMAKE_AR
#   CMAKE_RANLIB
#   CMAKE_COMPILER_IS_GNUCC
#
# If not already set before, it also sets
#   _CMAKE_TOOLCHAIN_PREFIX
33

34
include(${CMAKE_ROOT}/Modules/CMakeDetermineCompiler.cmake)
35

36
# Load system-specific compiler preferences for this language.
37 38 39 40
include(Platform/${CMAKE_SYSTEM_NAME}-C OPTIONAL)
if(NOT CMAKE_C_COMPILER_NAMES)
  set(CMAKE_C_COMPILER_NAMES cc)
endif()
41

42
if(${CMAKE_GENERATOR} MATCHES "Visual Studio")
43 44
elseif("${CMAKE_GENERATOR}" MATCHES "Xcode")
  set(CMAKE_C_COMPILER_XCODE_TYPE sourcecode.c.c)
45
  _cmake_find_compiler_path(C)
46 47 48 49 50
else()
  if(NOT CMAKE_C_COMPILER)
    set(CMAKE_C_COMPILER_INIT NOTFOUND)

    # prefer the environment variable CC
51
    if(NOT $ENV{CC} STREQUAL "")
52 53 54 55 56 57 58
      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()
59
    endif()
60 61 62 63 64 65

    # 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()
66
    endif()
67

68
    # finally list compilers to try
69
    if(NOT CMAKE_C_COMPILER_INIT)
70
      set(CMAKE_C_COMPILER_LIST ${_CMAKE_TOOLCHAIN_PREFIX}cc ${_CMAKE_TOOLCHAIN_PREFIX}gcc cl bcc xlc clang)
71
    endif()
72

73
    _cmake_find_compiler(C)
74

75
  else()
76
    _cmake_find_compiler_path(C)
77
  endif()
78
  mark_as_advanced(CMAKE_C_COMPILER)
79

80 81 82
  # 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.
83
  set(CMAKE_C_COMPILER_ID_TEST_FLAGS_FIRST)
84
  set(CMAKE_C_COMPILER_ID_TEST_FLAGS
85 86
    # Try compiling to an object file only.
    "-c"
Brad King's avatar
Brad King committed
87 88 89

    # Try enabling ANSI mode on HP.
    "-Aa"
90 91 92

    # Try compiling K&R-compatible code (needed by Bruce C Compiler).
    "-D__CLASSIC_C__"
93
    )
94 95 96 97 98
endif()

# Build a small source file to identify the compiler.
if(NOT CMAKE_C_COMPILER_ID_RUN)
  set(CMAKE_C_COMPILER_ID_RUN 1)
99

100
  # Try to identify the compiler.
101
  set(CMAKE_C_COMPILER_ID)
102
  set(CMAKE_C_PLATFORM_ID)
103
  file(READ ${CMAKE_ROOT}/Modules/CMakePlatformId.h.in
104
    CMAKE_C_COMPILER_ID_PLATFORM_CONTENT)
105 106

  # The IAR compiler produces weird output.
107
  # See https://cmake.org/Bug/view.php?id=10176#c19598
108 109 110 111
  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")

112 113 114 115 116 117 118 119
  # 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)

120
  include(${CMAKE_ROOT}/Modules/CMakeDetermineCompilerId.cmake)
121
  CMAKE_DETERMINE_COMPILER_ID(C CFLAGS CMakeCCompilerId.c)
Bill Hoffman's avatar
Bill Hoffman committed
122

123
  # Set old compiler and platform id variables.
124
  if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
125
    set(CMAKE_COMPILER_IS_GNUCC 1)
126
  endif()
127
  if(CMAKE_C_PLATFORM_ID MATCHES "MinGW")
128
    set(CMAKE_COMPILER_IS_MINGW 1)
129
  elseif(CMAKE_C_PLATFORM_ID MATCHES "Cygwin")
130
    set(CMAKE_COMPILER_IS_CYGWIN 1)
131 132
  endif()
endif()
133

134 135 136 137
if (NOT _CMAKE_TOOLCHAIN_LOCATION)
  get_filename_component(_CMAKE_TOOLCHAIN_LOCATION "${CMAKE_C_COMPILER}" PATH)
endif ()

138
# If we have a gcc cross compiler, they have usually some prefix, like
139 140
# 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).
141
# The other tools of the toolchain usually have the same prefix
142
# NAME_WE cannot be used since then this test will fail for names like
143
# "arm-unknown-nto-qnx6.3.0-gcc.exe", where BASENAME would be
144
# "arm-unknown-nto-qnx6" instead of the correct "arm-unknown-nto-qnx6.3.0-"
145 146
if (CMAKE_CROSSCOMPILING  AND NOT _CMAKE_TOOLCHAIN_PREFIX)

147
  if(CMAKE_C_COMPILER_ID MATCHES "GNU" OR CMAKE_C_COMPILER_ID MATCHES "Clang")
148
    get_filename_component(COMPILER_BASENAME "${CMAKE_C_COMPILER}" NAME)
149
    if (COMPILER_BASENAME MATCHES "^(.+-)(clang|g?cc)(-[0-9]+\\.[0-9]+\\.[0-9]+)?(\\.exe)?$")
150
      set(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_MATCH_1})
151
    elseif(CMAKE_C_COMPILER_ID MATCHES "Clang")
152 153 154
      if(CMAKE_C_COMPILER_TARGET)
        set(_CMAKE_TOOLCHAIN_PREFIX ${CMAKE_C_COMPILER_TARGET}-)
      endif()
155
    elseif(COMPILER_BASENAME MATCHES "qcc(\\.exe)?$")
156
      if(CMAKE_C_COMPILER_TARGET MATCHES "gcc_nto([^_le]+)(le)?")
157 158
        set(_CMAKE_TOOLCHAIN_PREFIX nto${CMAKE_MATCH_1}-)
      endif()
159 160 161 162 163 164 165
    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 ${CMAKE_MATCH_1})
    endif ()
166
  elseif(CMAKE_C_COMPILER_ID MATCHES "TI")
167 168 169 170 171 172
    # TI compilers are named e.g. cl6x, cl470 or armcl.exe
    get_filename_component(COMPILER_BASENAME "${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 ()
173
  endif()
174

175
endif ()
176

177 178 179 180
include(CMakeFindBinUtils)
if(MSVC_C_ARCHITECTURE_ID)
  set(SET_MSVC_C_ARCHITECTURE_ID
    "set(MSVC_C_ARCHITECTURE_ID ${MSVC_C_ARCHITECTURE_ID})")
181
endif()
182

Bill Hoffman's avatar
Bill Hoffman committed
183
# configure variables set in this file for fast reload later on
184
configure_file(${CMAKE_ROOT}/Modules/CMakeCCompiler.cmake.in
185
  ${CMAKE_PLATFORM_INFO_DIR}/CMakeCCompiler.cmake
186
  @ONLY
187
  )
188
set(CMAKE_C_COMPILER_ENV_VAR "CC")