vcpkg/ports/libsodium/CMakeLists.txt
2019-07-17 16:24:26 -07:00

743 lines
22 KiB
CMake

cmake_minimum_required(VERSION 3.9)
file(STRINGS ${CMAKE_CURRENT_LIST_DIR}/configure.ac config_ac_contents)
foreach (line ${config_ac_contents})
if (line MATCHES "AC_INIT\\(\\[libsodium\\],\\[([0-9.]+)\\],")
set(VERSION ${CMAKE_MATCH_1})
elseif (line MATCHES "SODIUM_LIBRARY_VERSION_(MAJOR|MINOR)=([0-9]+)")
set(SODIUM_LIBRARY_VERSION_${CMAKE_MATCH_1} ${CMAKE_MATCH_2})
endif ()
endforeach ()
message("VERSION: ${VERSION}")
message("SODIUM_LIBRARY_VERSION_MAJOR: ${SODIUM_LIBRARY_VERSION_MAJOR}")
message("SODIUM_LIBRARY_VERSION_MINOR: ${SODIUM_LIBRARY_VERSION_MINOR}")
project(sodium VERSION ${VERSION} LANGUAGES C ASM)
include(CheckCSourceCompiles)
include(CheckFunctionExists)
include(CheckIncludeFile)
include(CMakePackageConfigHelpers)
include(CTest)
include(GNUInstallDirs)
include(TestBigEndian)
set(CMAKE_C_STANDARD 99)
set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
set(CMAKE_DISABLE_SOURCE_CHANGES ON)
set(CMAKE_DISABLE_IN_SOURCE_BUILD ON)
option(BUILD_SHARED_LIBS "Build shared library" ${BUILD_SHARED_LIBS})
option(ENABLE_SSP "Compile with -fstack-protector" ON)
option(ENABLE_PIE "Compile with -fPIE" ON)
option(ENABLE_BLOCKING_RANDOM "Enable blocking random" OFF)
option(ENABLE_MINIMAL "Only compile the minimum set of functions required for the high-level API" OFF)
option(ENABLE_PTHREADS "Use pthreads library" ON)
option(ENABLE_RETPOLINE "Use return trampolines for indirect calls" OFF)
if (ENABLE_MINIMAL)
set(SODIUM_LIBRARY_MINIMAL_DEF "#define SODIUM_LIBRARY_MINIMAL 1")
endif ()
configure_file(
src/libsodium/include/sodium/version.h.in
${CMAKE_BINARY_DIR}/sodium/version.h
)
file(GLOB sodium_headers
${PROJECT_SOURCE_DIR}/src/libsodium/include/sodium/*.h
${PROJECT_SOURCE_DIR}/src/libsodium/include/sodium.h
${CMAKE_BINARY_DIR}/sodium/version.h
)
if (UNIX)
file(GLOB_RECURSE sodium_sources
${PROJECT_SOURCE_DIR}/src/libsodium/*.c
${PROJECT_SOURCE_DIR}/src/libsodium/*.S # HAVE_AVX_ASM
)
else ()
file(GLOB_RECURSE sodium_sources
${PROJECT_SOURCE_DIR}/src/libsodium/*.c
)
endif ()
if (MSVC)
enable_language(RC)
list(APPEND sodium_sources
builds/msvc/resource.rc
)
endif ()
add_library(${PROJECT_NAME}
${sodium_headers}
${sodium_sources}
)
set_target_properties(${PROJECT_NAME}
PROPERTIES
PREFIX ""
OUTPUT_NAME "lib${PROJECT_NAME}"
)
test_big_endian(IS_BIG_ENDIAN)
if (IS_BIG_ENDIAN)
target_compile_definitions(${PROJECT_NAME} PRIVATE NATIVE_BIG_ENDIAN)
else ()
target_compile_definitions(${PROJECT_NAME} PRIVATE NATIVE_LITTLE_ENDIAN)
endif ()
macro (sodium_check_func func var)
check_function_exists(${func} ${var})
if (${var})
target_compile_definitions(${PROJECT_NAME} PRIVATE ${var}=1)
endif ()
endmacro ()
if (MSVC)
target_compile_options(${PROJECT_NAME}
PRIVATE
/D_CONSOLE
/D_CRT_SECURE_NO_WARNINGS
/DCPU_UNALIGNED_ACCESS=1
/MP
/Dinline=__inline
/wd4068 # Unknown pragma
/wd4197
/wd4244 # Macro redefinition
)
target_link_libraries(${PROJECT_NAME}
PUBLIC
advapi32
)
else ()
if (ENABLE_BLOCKING_RANDOM)
target_compile_definitions(${PROJECT_NAME} PRIVATE USE_BLOCKING_RANDOM)
endif ()
if (ENABLE_PTHREADS)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_PTHREAD)
target_compile_options(${PROJECT_NAME} PRIVATE -ftls-model=local-dynamic)
target_compile_options(${PROJECT_NAME} PUBLIC -pthread)
endif ()
if (ENABLE_SSP)
target_compile_options(${PROJECT_NAME} PRIVATE -fstack-protector-all)
endif ()
if (ENABLE_PIE)
target_compile_options(${PROJECT_NAME} PRIVATE -fPIE)
endif ()
if (ENABLE_RETPOLINE)
target_compile_options(${PROJECT_NAME}
PRIVATE
-mindirect-branch=thunk-inline
-mindirect-branch-register
)
endif ()
target_compile_options(${PROJECT_NAME}
PRIVATE
-flax-vector-conversions
-fvisibility=hidden
-fPIC
-fwrapv
-Wall
-Wextra
-Wbad-function-cast
-Wcast-qual
#-Wdiv-by-zero
#-Wduplicated-branches
#-Wduplicated-cond
-Wfloat-equal
-Wformat=2
-Wlogical-op
-Wmaybe-uninitialized
#-Wmisleading-indentation
-Wmissing-declarations
-Wmissing-prototypes
-Wnested-externs
#-Wno-type-limits
#-Wno-unknown-pragmas
-Wnormalized=id
#-Wnull-dereference
-Wold-style-declaration
-Wpointer-arith
-Wredundant-decls
#-Wrestrict
#-Wsometimes-uninitialized
-Wstrict-prototypes
-Wswitch-enum
#-Wvariable-decl
-Wwrite-strings
-Wl,-z,relro
-Wl,-z,now
-Wl,-z,noexecstack
)
if (CMAKE_C_COMPILER_ID STREQUAL "Clang" OR
CMAKE_C_COMPILER_ID STREQUAL "AppleClang")
target_compile_options(${PROJECT_NAME}
PRIVATE
-Wno-unknown-warning-option
-Wshorten-64-to-32
)
endif ()
check_include_file(sys/mman.h HAVE_SYS_MMAN_H)
if (HAVE_SYS_MMAN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_SYS_MMAN_H)
endif ()
sodium_check_func(arc4random HAVE_SAFE_ARC4RANDOM)
sodium_check_func(mmap HAVE_MMAP)
sodium_check_func(mlock HAVE_MLOCK)
sodium_check_func(madvise HAVE_MADVISE)
sodium_check_func(mprotect HAVE_MPROTECT)
sodium_check_func(memset_s HAVE_MEMSET_S)
sodium_check_func(explicit_bzero HAVE_EXPLICIT_BZERO)
sodium_check_func(explicit_memset HAVE_EXPLICIT_MEMSET)
sodium_check_func(nanosleep HAVE_NANOSLEEP)
sodium_check_func(posix_memalign HAVE_POSIX_MEMALIGN)
sodium_check_func(getpid HAVE_GETPID)
check_c_source_compiles(
"
#pragma GCC target(\"mmx\")
#include <mmintrin.h>
int main(void)
{
__m64 x = _mm_setzero_si64();
}
"
HAVE_MMINTRIN_H
)
if (HAVE_MMINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_MMINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -mmmx)
endif ()
check_c_source_compiles(
"
#pragma GCC target(\"sse2\")
#ifndef __SSE2__
# define __SSE2__
#endif
#include <emmintrin.h>
int main(void) {
__m128d x = _mm_setzero_pd();
__m128i z = _mm_srli_epi64(_mm_setzero_si128(), 26);
}
"
HAVE_EMMINTRIN_H
)
if (HAVE_EMMINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_EMMINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -msse2)
endif ()
check_c_source_compiles(
"
#pragma GCC target(\"sse3\")
#include <pmmintrin.h>
int main(void) {
__m128 x = _mm_addsub_ps(_mm_cvtpd_ps(_mm_setzero_pd()), _mm_cvtpd_ps(_mm_setzero_pd()));
}
"
HAVE_PMMINTRIN_H
)
if (HAVE_PMMINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_PMMINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -msse3)
endif ()
check_c_source_compiles(
"
#pragma GCC target(\"ssse3\")
#include <tmmintrin.h>
int main(void) {
__m64 x = _mm_abs_pi32(_m_from_int(0));
}
"
HAVE_TMMINTRIN_H
)
if (HAVE_TMMINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_TMMINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -mssse3)
endif ()
check_c_source_compiles(
"
#pragma GCC target(\"sse4.1\")
#include <smmintrin.h>
int main(void) {
__m128i x = _mm_minpos_epu16(_mm_setzero_si128());
}
"
HAVE_SMMINTRIN_H
)
if (HAVE_SMMINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_SMMINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -msse4.1)
endif ()
check_c_source_compiles(
"
#ifdef __native_client__
# error NativeClient detected - Avoiding AVX opcodes
#endif
#pragma GCC target(\"avx\")
#include <immintrin.h>
int main(void) {
_mm256_zeroall();
}
"
HAVE_AVXINTRIN_H
)
if (HAVE_AVXINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_AVXINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -mavx)
endif ()
check_c_source_compiles(
"
#ifdef __native_client__
# error NativeClient detected - Avoiding AVX2 opcodes
#endif
#pragma GCC target(\"avx2\")
#include <immintrin.h>
int main(void) {
__m256 x = _mm256_set1_ps(3.14);
__m256 y = _mm256_permutevar8x32_ps(x, _mm256_set1_epi32(42));
return _mm256_movemask_ps(_mm256_cmp_ps(x, y, _CMP_NEQ_OQ));
}
"
HAVE_AVX2INTRIN_H
)
if (HAVE_AVX2INTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_AVX2INTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -mavx2)
check_c_source_compiles(
"
#ifdef __native_client__
# error NativeClient detected - Avoiding AVX2 opcodes
#endif
#pragma GCC target(\"avx2\")
#include <immintrin.h>
int main(void) {
__m256i y = _mm256_broadcastsi128_si256(_mm_setzero_si128());
}
"
_mm256_broadcastsi128_si256_DEFINED
)
if (NOT _mm256_broadcastsi128_si256_DEFINED)
target_compile_definitions(${PROJECT_NAME}
PRIVATE
_mm256_broadcastsi128_si256=_mm_broadcastsi128_si256
)
endif ()
endif ()
check_c_source_compiles(
"
#ifdef __native_client__
# error NativeClient detected - Avoiding AVX512F opcodes
#endif
#pragma GCC target(\"avx512f\")
#include <immintrin.h>
#ifndef __AVX512F__
# error No AVX512 support
#elif defined(__clang__)
# if __clang_major__ < 4
# error Compiler AVX512 support may be broken
# endif
#elif defined(__GNUC__)
# if __GNUC__ < 6
# error Compiler AVX512 support may be broken
# endif
#endif
int main(void) {
__m512i x = _mm512_setzero_epi32();
__m512i y = _mm512_permutexvar_epi64(_mm512_setr_epi64(0, 1, 4, 5, 2, 3, 6, 7), x);
}
"
HAVE_AVX512FINTRIN_H
)
if (HAVE_AVX512FINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_AVX512FINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -mavx512f)
else ()
target_compile_options(${PROJECT_NAME} PRIVATE -mno-avx512f)
endif ()
check_c_source_compiles(
"
#ifdef __native_client__
# error NativeClient detected - Avoiding AESNI opcodes
#endif
#pragma GCC target(\"aes\")
#pragma GCC target(\"pclmul\")
#include <wmmintrin.h>
int main(void) {
__m128i x = _mm_aesimc_si128(_mm_setzero_si128());
__m128i y = _mm_clmulepi64_si128(_mm_setzero_si128(), _mm_setzero_si128(), 0);
}
"
HAVE_WMMINTRIN_H
)
if (HAVE_WMMINTRIN_H)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_WMMINTRIN_H=1)
target_compile_options(${PROJECT_NAME} PRIVATE -maes -mpclmul)
endif ()
check_c_source_compiles(
"
#ifdef __native_client__
# error NativeClient detected - Avoiding RDRAND opcodes
#endif
#pragma GCC target(\"rdrnd\")
#include <immintrin.h>
int main(void) {
unsigned long long x;
_rdrand64_step(&x);
}
"
HAVE_RDRAND
)
if (HAVE_RDRAND)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_RDRAND=1)
target_compile_options(${PROJECT_NAME} PRIVATE -mrdrnd)
endif ()
check_c_source_compiles(
"
#include <intrin.h>
int main(void) {
(void) _xgetbv(0);
}
"
HAVE__XGETBV
)
if (HAVE__XGETBV)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE__XGETBV=1)
endif ()
check_c_source_compiles(
"
int main(void) {
int a = 42;
int *pnt = &a;
__asm__ __volatile__ (\"\" : : \"r\"(pnt) : \"memory\");
}
"
HAVE_INLINE_ASM
)
if (HAVE_INLINE_ASM)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_INLINE_ASM=1)
endif ()
check_c_source_compiles(
"
int main(void) {
#if defined(__amd64) || defined(__amd64__) || defined(__x86_64__)
# if defined(__CYGWIN__) || defined(__MINGW32__) || defined(__MINGW64__) || defined(_WIN32) || defined(_WIN64)
# error Windows x86_64 calling conventions are not supported yet
# endif
/* neat */
#else
# error !x86_64
#endif
unsigned char i = 0, o = 0, t;
__asm__ __volatile__ (\"pxor %%xmm12, %%xmm6 \n\"
\"movb (%[i]), %[t] \n\"
\"addb %[t], (%[o]) \n\"
: [t] \"=&r\"(t)
: [o] \"D\"(&o), [i] \"S\"(&i)
: \"memory\", \"flags\", \"cc\");
}
"
HAVE_AMD64_ASM
)
if (HAVE_AMD64_ASM)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_AMD64_ASM=1)
endif ()
check_c_source_compiles(
"
int main(void) {
#if defined(__amd64) || defined(__amd64__) || defined(__x86_64__)
# if defined(__CYGWIN__) || defined(__MINGW32__) || defined(__MINGW64__) || defined(_WIN32) || defined(_WIN64)
# error Windows x86_64 calling conventions are not supported yet
# endif
/* neat */
#else
# error !x86_64
#endif
__asm__ __volatile__ (\"vpunpcklqdq %xmm0,%xmm13,%xmm0\");
}
"
HAVE_AVX_ASM
)
if (HAVE_AVX_ASM)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_AVX_ASM=1)
endif ()
check_c_source_compiles(
"
#if !defined(__clang__) && !defined(__GNUC__) && !defined(__SIZEOF_INT128__)
# error mode(TI) is a gcc extension, and __int128 is not available
#endif
#if defined(__clang__) && !defined(__x86_64__) && !defined(__aarch64__)
# error clang does not properly handle the 128-bit type on 32-bit systems
#endif
#ifndef NATIVE_LITTLE_ENDIAN
# error libsodium currently expects a little endian CPU for the 128-bit type
#endif
#ifdef __EMSCRIPTEN__
# error emscripten currently doesn't support some operations on integers larger than 64 bits
#endif
#include <stddef.h>
#include <stdint.h>
#if defined(__SIZEOF_INT128__)
typedef unsigned __int128 uint128_t;
#else
typedef unsigned uint128_t __attribute__((mode(TI)));
#endif
void fcontract(uint128_t *t) {
*t += 0x8000000000000 - 1;
*t *= *t;
*t >>= 84;
}
int main(void) {
(void) fcontract;
}
"
HAVE_TI_MODE
)
if (HAVE_TI_MODE)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_TI_MODE=1)
endif ()
check_c_source_compiles(
"
int main(void) {
unsigned int cpu_info[4];
__asm__ __volatile__ (\"xchgl %%ebx, %k1; cpuid; xchgl %%ebx, %k1\" :
\"=a\" (cpu_info[0]), \"=&r\" (cpu_info[1]),
\"=c\" (cpu_info[2]), \"=d\" (cpu_info[3]) :
\"0\" (0U), \"2\" (0U));
}
"
HAVE_CPUID
)
if (HAVE_CPUID)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_CPUID=1)
endif ()
check_c_source_compiles(
"
#if !defined(__ELF__) && !defined(__APPLE_CC__)
# error Support for weak symbols may not be available
#endif
__attribute__((weak)) void __dummy(void *x) { }
void f(void *x) { __dummy(x); }
int main(void) {}
"
HAVE_WEAK_SYMBOLS
)
if (HAVE_WEAK_SYMBOLS)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_WEAK_SYMBOLS=1)
endif ()
check_c_source_compiles(
"
int main(void) {
static volatile int _sodium_lock;
__sync_lock_test_and_set(&_sodium_lock, 1);
__sync_lock_release(&_sodium_lock);
}
"
HAVE_ATOMIC_OPS
)
if (HAVE_ATOMIC_OPS)
target_compile_definitions(${PROJECT_NAME} PRIVATE HAVE_ATOMIC_OPS=1)
endif ()
check_c_source_compiles(
"
#include <limits.h>
#include <stdint.h>
int main(void) {
(void) SIZE_MAX;
(void) UINT64_MAX;
}
"
STDC_LIMIT_MACROS_REQUIRED
)
if (STDC_LIMIT_MACROS_REQUIRED)
target_compile_definitions(${PROJECT_NAME}
PRIVATE
__STDC_LIMIT_MACROS
__STDC_CONSTANT_MACROS
)
endif ()
# include/sodium/private/common.h
target_compile_definitions(${PROJECT_NAME} PRIVATE CONFIGURED=1)
endif ()
if (BUILD_SHARED_LIBS)
if (MSVC)
target_compile_definitions(${PROJECT_NAME}
PRIVATE
SODIUM_DLL_EXPORT
)
endif ()
else ()
target_compile_definitions(${PROJECT_NAME}
PUBLIC
SODIUM_STATIC
)
endif ()
target_include_directories(${PROJECT_NAME}
PRIVATE
$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src/libsodium/include/sodium>
$<BUILD_INTERFACE:${CMAKE_BINARY_DIR}/sodium>
)
if (BUILD_TESTING)
file(GLOB sodium_test_sources ${PROJECT_SOURCE_DIR}/test/default/*.c)
foreach (test_src ${sodium_test_sources})
get_filename_component(test_name ${test_src} NAME_WE)
add_executable(${test_name} ${test_src})
if (MSVC)
target_compile_definitions(${test_name} PRIVATE _CRT_SECURE_NO_WARNINGS)
endif ()
target_include_directories(${test_name}
PRIVATE
$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src/libsodium/include>
$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src/libsodium/include/sodium>
$<BUILD_INTERFACE:${CMAKE_BINARY_DIR}>
$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/test/quirks>
)
target_link_libraries(${test_name} PRIVATE ${PROJECT_NAME})
add_custom_command(TARGET ${test_name} POST_BUILD
COMMAND ${CMAKE_COMMAND} -E copy_if_different
"${CMAKE_CURRENT_LIST_DIR}/test/default/${test_name}.exp"
$<TARGET_FILE_DIR:${test_name}>)
add_test(
NAME ${test_name}
COMMAND ${test_name}
WORKING_DIRECTORY $<TARGET_FILE_DIR:${test_name}>
)
endforeach ()
endif ()
install(DIRECTORY src/libsodium/include/
DESTINATION include/
USE_SOURCE_PERMISSIONS
PATTERN "*.h"
PATTERN "*.h.in" EXCLUDE
REGEX "private($|/)" EXCLUDE
)
install(FILES ${CMAKE_BINARY_DIR}/sodium/version.h
DESTINATION include/sodium
)
install(TARGETS ${PROJECT_NAME}
EXPORT ${PROJECT_NAME}-targets
ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
INCLUDES DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
)
install(EXPORT ${PROJECT_NAME}-targets
FILE unofficial-${PROJECT_NAME}Targets.cmake
NAMESPACE unofficial-${PROJECT_NAME}::
DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/unofficial-${PROJECT_NAME}
)
set(TARGET_NAME unofficial-${PROJECT_NAME}::${PROJECT_NAME})
configure_package_config_file(
${PROJECT_NAME}Config.cmake.in
${CMAKE_CURRENT_BINARY_DIR}/unofficial-${PROJECT_NAME}Config.cmake
INSTALL_DESTINATION ${PROJECT_BINARY_DIR}
)
write_basic_package_version_file(
${CMAKE_CURRENT_BINARY_DIR}/unofficial-${PROJECT_NAME}ConfigVersion.cmake
VERSION ${VERSION}
COMPATIBILITY AnyNewerVersion
)
unset(TARGET_NAME)
install(
FILES
${CMAKE_CURRENT_BINARY_DIR}/unofficial-${PROJECT_NAME}Config.cmake
${CMAKE_CURRENT_BINARY_DIR}/unofficial-${PROJECT_NAME}ConfigVersion.cmake
DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/unofficial-${PROJECT_NAME}
)
# References:
# https://github.com/boost-cmake/bcm/wiki/Cmake-best-practices-and-guidelines
# https://github.com/jedisct1/libsodium/pull/74/files
# https://github.com/jedisct1/libsodium/pull/156/files
# https://github.com/jedisct1/libsodium/pull/181/files
# https://github.com/jedisct1/libsodium/issues/378
# https://github.com/jedisct1/libsodium/issues/636
# https://github.com/jedisct1/libsodium/issues/771
# https://github.com/jedisct1/libsodium/blob/gyp/sodium.gyp
# https://github.com/imefisto/cmake-libsodium
# https://github.com/Cyberunner23/libsodium-CMake
# https://stackoverflow.com/questions/29901352/appending-to-cmake-c-flags
# https://stackoverflow.com/questions/986426/what-do-stdc-limit-macros-and-stdc-constant-macros-mean
# https://gcc.gnu.org/onlinedocs/gcc/Option-Summary.html
# https://stackoverflow.com/questions/15132185/mixing-c-and-assembly-sources-and-build-with-cmake
# https://stackoverflow.com/questions/647892/how-to-check-header-files-and-library-functions-in-cmake-like-it-is-done-in-auto
# https://stackoverflow.com/questions/31038963/how-do-you-rename-a-library-filename-in-cmake