xref: /openbsd-src/gnu/llvm/libunwind/cmake/config-ix.cmake (revision 0faf1914bfa030ea6c1d961758e08514a79ff73a)
1include(CMakePushCheckState)
2include(CheckCCompilerFlag)
3include(CheckCXXCompilerFlag)
4include(CheckLibraryExists)
5include(LLVMCheckCompilerLinkerFlag)
6include(CheckSymbolExists)
7include(CheckCSourceCompiles)
8
9# The compiler driver may be implicitly trying to link against libunwind, which
10# might not work if libunwind doesn't exist yet. Try to check if
11# --unwindlib=none is supported, and use that if possible.
12llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
13
14check_library_exists(c fopen "" LIBUNWIND_HAS_C_LIB)
15
16if (NOT LIBUNWIND_USE_COMPILER_RT)
17  if (ANDROID)
18    check_library_exists(gcc __gcc_personality_v0 "" LIBUNWIND_HAS_GCC_LIB)
19  else ()
20    check_library_exists(gcc_s __gcc_personality_v0 "" LIBUNWIND_HAS_GCC_S_LIB)
21    check_library_exists(gcc __absvdi2 "" LIBUNWIND_HAS_GCC_LIB)
22  endif ()
23endif()
24
25# libunwind is using -nostdlib++ at the link step when available,
26# otherwise -nodefaultlibs is used. We want all our checks to also
27# use one of these options, otherwise we may end up with an inconsistency between
28# the flags we think we require during configuration (if the checks are
29# performed without one of those options) and the flags that are actually
30# required during compilation (which has the -nostdlib++ or -nodefaultlibs). libc is
31# required for the link to go through. We remove sanitizers from the
32# configuration checks to avoid spurious link errors.
33
34llvm_check_compiler_linker_flag(CXX "-nostdlib++" CXX_SUPPORTS_NOSTDLIBXX_FLAG)
35if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
36  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
37else()
38  llvm_check_compiler_linker_flag(C "-nodefaultlibs" C_SUPPORTS_NODEFAULTLIBS_FLAG)
39  if (C_SUPPORTS_NODEFAULTLIBS_FLAG)
40    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nodefaultlibs")
41  endif()
42endif()
43
44if (CXX_SUPPORTS_NOSTDLIBXX_FLAG OR C_SUPPORTS_NODEFAULTLIBS_FLAG)
45  if (LIBUNWIND_HAS_C_LIB)
46    list(APPEND CMAKE_REQUIRED_LIBRARIES c)
47  endif ()
48  if (LIBUNWIND_USE_COMPILER_RT)
49    include(HandleCompilerRT)
50    find_compiler_rt_library(builtins LIBUNWIND_BUILTINS_LIBRARY
51                             FLAGS ${LIBUNWIND_COMPILE_FLAGS})
52    list(APPEND CMAKE_REQUIRED_LIBRARIES "${LIBUNWIND_BUILTINS_LIBRARY}")
53  else ()
54    if (LIBUNWIND_HAS_GCC_S_LIB)
55      list(APPEND CMAKE_REQUIRED_LIBRARIES gcc_s)
56    endif ()
57    if (LIBUNWIND_HAS_GCC_LIB)
58      list(APPEND CMAKE_REQUIRED_LIBRARIES gcc)
59    endif ()
60  endif ()
61  if (MINGW)
62    # Mingw64 requires quite a few "C" runtime libraries in order for basic
63    # programs to link successfully with -nodefaultlibs.
64    if (LIBUNWIND_USE_COMPILER_RT)
65      set(MINGW_RUNTIME ${LIBUNWIND_BUILTINS_LIBRARY})
66    else ()
67      set(MINGW_RUNTIME gcc_s gcc)
68    endif()
69    set(MINGW_LIBRARIES mingw32 ${MINGW_RUNTIME} moldname mingwex msvcrt advapi32
70                        shell32 user32 kernel32 mingw32 ${MINGW_RUNTIME}
71                        moldname mingwex msvcrt)
72    list(APPEND CMAKE_REQUIRED_LIBRARIES ${MINGW_LIBRARIES})
73  endif()
74  if (CMAKE_C_FLAGS MATCHES -fsanitize OR CMAKE_CXX_FLAGS MATCHES -fsanitize)
75    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -fno-sanitize=all")
76  endif ()
77  if (CMAKE_C_FLAGS MATCHES -fsanitize-coverage OR CMAKE_CXX_FLAGS MATCHES -fsanitize-coverage)
78    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -fsanitize-coverage=0")
79  endif ()
80endif ()
81
82# Check compiler pragmas
83if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
84  cmake_push_check_state()
85  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror=unknown-pragmas")
86  check_c_source_compiles("
87#pragma comment(lib, \"c\")
88int main(void) { return 0; }
89" C_SUPPORTS_COMMENT_LIB_PRAGMA)
90  cmake_pop_check_state()
91endif()
92
93# Check compiler flags
94check_cxx_compiler_flag(-nostdinc++ CXX_SUPPORTS_NOSTDINCXX_FLAG)
95
96# Check symbols
97check_symbol_exists(__arm__ "" LIBUNWIND_TARGET_ARM)
98check_symbol_exists(__USING_SJLJ_EXCEPTIONS__ "" LIBUNWIND_USES_SJLJ_EXCEPTIONS)
99check_symbol_exists(__ARM_DWARF_EH__ "" LIBUNWIND_USES_DWARF_EH)
100
101if(LIBUNWIND_TARGET_ARM AND NOT LIBUNWIND_USES_SJLJ_EXCEPTIONS AND NOT LIBUNWIND_USES_DWARF_EH)
102  # This condition is copied from __libunwind_config.h
103  set(LIBUNWIND_USES_ARM_EHABI ON)
104endif()
105
106# Check libraries
107if(FUCHSIA)
108  set(LIBUNWIND_HAS_DL_LIB NO)
109  set(LIBUNWIND_HAS_PTHREAD_LIB NO)
110else()
111  check_library_exists(dl dladdr "" LIBUNWIND_HAS_DL_LIB)
112  check_library_exists(pthread pthread_once "" LIBUNWIND_HAS_PTHREAD_LIB)
113endif()
114