1# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
2# file Copyright.txt or https://cmake.org/licensing for details.
3
4include(Compiler/CMakeCommonCompilerMacros)
5
6if(CMAKE_C_COMPILER_VERSION VERSION_GREATER_EQUAL 19.27)
7  set(CMAKE_C90_STANDARD_COMPILE_OPTION "")
8  set(CMAKE_C90_EXTENSION_COMPILE_OPTION "")
9  set(CMAKE_C99_STANDARD_COMPILE_OPTION "")
10  set(CMAKE_C99_EXTENSION_COMPILE_OPTION "")
11  set(CMAKE_C11_STANDARD_COMPILE_OPTION "-std:c11")
12  set(CMAKE_C11_EXTENSION_COMPILE_OPTION "-std:c11")
13
14  if(CMAKE_C_COMPILER_VERSION VERSION_GREATER_EQUAL 19.28)
15    set(CMAKE_C90_STANDARD__HAS_FULL_SUPPORT ON)
16    set(CMAKE_C99_STANDARD__HAS_FULL_SUPPORT ON)
17    set(CMAKE_C11_STANDARD__HAS_FULL_SUPPORT ON)
18    set(CMAKE_C17_STANDARD_COMPILE_OPTION "-std:c17")
19    set(CMAKE_C17_EXTENSION_COMPILE_OPTION "-std:c17")
20  else()
21    # Special case for 19.27 (VS 16.7): C11 has partial support.
22    macro(cmake_record_c_compile_features)
23      _has_compiler_features_c(90)
24      _has_compiler_features_c(99)
25      list(APPEND CMAKE_C11_COMPILE_FEATURES c_std_11)
26      set(_result 0) # expected by cmake_determine_compile_features
27    endmacro()
28  endif()
29
30  __compiler_check_default_language_standard(C 19.27 99)
31else()
32  # MSVC has no specific options to set C language standards, but set them as
33  # empty strings anyways so the feature test infrastructure can at least check
34  # to see if they are defined.
35  set(CMAKE_C90_STANDARD_COMPILE_OPTION "")
36  set(CMAKE_C90_EXTENSION_COMPILE_OPTION "")
37  set(CMAKE_C99_STANDARD_COMPILE_OPTION "")
38  set(CMAKE_C99_EXTENSION_COMPILE_OPTION "")
39  set(CMAKE_C11_STANDARD_COMPILE_OPTION "")
40  set(CMAKE_C11_EXTENSION_COMPILE_OPTION "")
41
42  # There is no meaningful default for this
43  set(CMAKE_C_STANDARD_DEFAULT "")
44
45  # There are no C compiler modes so we hard-code the known compiler supported
46  # features. Override the default macro for this special case.  Pretend that
47  # all language standards are available so that at least compilation
48  # can be attempted.
49  macro(cmake_record_c_compile_features)
50    list(APPEND CMAKE_C_COMPILE_FEATURES
51      c_std_90
52      c_std_99
53      c_std_11
54      c_std_17
55      c_std_23
56      c_function_prototypes
57      )
58    list(APPEND CMAKE_C90_COMPILE_FEATURES c_std_90 c_function_prototypes)
59    list(APPEND CMAKE_C99_COMPILE_FEATURES c_std_99)
60    list(APPEND CMAKE_C11_COMPILE_FEATURES c_std_11)
61    if (CMAKE_C_COMPILER_VERSION VERSION_GREATER_EQUAL 14.0)
62      list(APPEND CMAKE_C_COMPILE_FEATURES c_variadic_macros)
63      list(APPEND CMAKE_C99_COMPILE_FEATURES c_variadic_macros)
64    endif()
65    set(_result 0) # expected by cmake_determine_compile_features
66  endmacro()
67endif()
68
69set(CMAKE_C_COMPILE_OPTIONS_EXPLICIT_LANGUAGE -TC)
70set(CMAKE_C_CLANG_TIDY_DRIVER_MODE "cl")
71set(CMAKE_C_INCLUDE_WHAT_YOU_USE_DRIVER_MODE "cl")
72
73# /JMC "Just My Code" is only supported by MSVC 19.05 onward.
74if (CMAKE_C_COMPILER_VERSION VERSION_GREATER_EQUAL 19.05)
75  set(CMAKE_C_COMPILE_OPTIONS_JMC "-JMC")
76endif()
77
78# The `/external:I` flag was made non-experimental in 19.29.30036.3.
79if (CMAKE_C_COMPILER_VERSION VERSION_GREATER_EQUAL 19.29.30036.3)
80  set(CMAKE_INCLUDE_SYSTEM_FLAG_C "-external:I ")
81  set(_CMAKE_INCLUDE_SYSTEM_FLAG_C_WARNING "-external:W0 ")
82endif ()
83