MSVC CMake generation optimization (#2852)

This commit is contained in:
Mattias Ljungström
2022-04-08 15:27:23 +02:00
committed by GitHub
parent 22d31b31f0
commit a935ac3e60
5 changed files with 32 additions and 41 deletions

View File

@@ -1,7 +1,11 @@
# C++14 feature support detection
include(CheckCXXSourceCompiles)
include(CheckCXXCompilerFlag)
function (fmt_check_cxx_compiler_flag flag result)
if (NOT MSVC)
check_cxx_compiler_flag("${flag}" ${result})
endif ()
endfunction ()
if (NOT CMAKE_CXX_STANDARD)
set(CMAKE_CXX_STANDARD 11)
@@ -9,35 +13,38 @@ endif()
message(STATUS "CXX_STANDARD: ${CMAKE_CXX_STANDARD}")
if (CMAKE_CXX_STANDARD EQUAL 20)
check_cxx_compiler_flag(-std=c++20 has_std_20_flag)
check_cxx_compiler_flag(-std=c++2a has_std_2a_flag)
fmt_check_cxx_compiler_flag(-std=c++20 has_std_20_flag)
fmt_check_cxx_compiler_flag(-std=c++2a has_std_2a_flag)
if (has_std_20_flag)
set(CXX_STANDARD_FLAG -std=c++20)
elseif (has_std_2a_flag)
set(CXX_STANDARD_FLAG -std=c++2a)
endif ()
elseif (CMAKE_CXX_STANDARD EQUAL 17)
check_cxx_compiler_flag(-std=c++17 has_std_17_flag)
check_cxx_compiler_flag(-std=c++1z has_std_1z_flag)
fmt_check_cxx_compiler_flag(-std=c++17 has_std_17_flag)
fmt_check_cxx_compiler_flag(-std=c++1z has_std_1z_flag)
if (has_std_17_flag)
set(CXX_STANDARD_FLAG -std=c++17)
elseif (has_std_1z_flag)
set(CXX_STANDARD_FLAG -std=c++1z)
endif ()
elseif (CMAKE_CXX_STANDARD EQUAL 14)
check_cxx_compiler_flag(-std=c++14 has_std_14_flag)
check_cxx_compiler_flag(-std=c++1y has_std_1y_flag)
fmt_check_cxx_compiler_flag(-std=c++14 has_std_14_flag)
fmt_check_cxx_compiler_flag(-std=c++1y has_std_1y_flag)
if (has_std_14_flag)
set(CXX_STANDARD_FLAG -std=c++14)
elseif (has_std_1y_flag)
set(CXX_STANDARD_FLAG -std=c++1y)
endif ()
elseif (CMAKE_CXX_STANDARD EQUAL 11)
check_cxx_compiler_flag(-std=c++11 has_std_11_flag)
check_cxx_compiler_flag(-std=c++0x has_std_0x_flag)
fmt_check_cxx_compiler_flag(-std=c++11 has_std_11_flag)
fmt_check_cxx_compiler_flag(-std=c++0x has_std_0x_flag)
if (has_std_11_flag)
set(CXX_STANDARD_FLAG -std=c++11)
@@ -45,26 +52,3 @@ elseif (CMAKE_CXX_STANDARD EQUAL 11)
set(CXX_STANDARD_FLAG -std=c++0x)
endif ()
endif ()
set(CMAKE_REQUIRED_FLAGS ${CXX_STANDARD_FLAG})
# Check if user-defined literals are available
check_cxx_source_compiles("
void operator\"\" _udl(long double);
int main() {}"
SUPPORTS_USER_DEFINED_LITERALS)
if (NOT SUPPORTS_USER_DEFINED_LITERALS)
set (SUPPORTS_USER_DEFINED_LITERALS OFF)
endif ()
# Check if <variant> is available
set(CMAKE_REQUIRED_FLAGS -std=c++1z)
check_cxx_source_compiles("
#include <variant>
int main() {}"
FMT_HAS_VARIANT)
if (NOT FMT_HAS_VARIANT)
set (FMT_HAS_VARIANT OFF)
endif ()
set(CMAKE_REQUIRED_FLAGS )