1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
|
# Copied from
# https://github.com/dev-cafe/cmake-cookbook/blob/master/chapter-07/recipe-03/c-cxx-example/set_compiler_flag.cmake
# Adapted from
# https://github.com/robertodr/ddPCM/blob/expose-C-api/cmake/custom/compilers/SetCompilerFlag.cmake
# which was adapted by Roberto Di Remigio from
# https://github.com/SethMMorton/cmake_fortran_template/blob/master/cmake/Modules/SetCompileFlag.cmake
# Given a list of flags, this stateless function will try each, one at a time,
# and set result to the first flag that works.
# If none of the flags works, result is "".
# If the REQUIRED key is given and no flag is found, a FATAL_ERROR is raised.
#
# Call is:
# set_compile_flag(result (Fortran|C|CXX) <REQUIRED> flag1 flag2 ...)
#
# Example:
# set_compiler_flag(working_compile_flag C REQUIRED "-Wall" "-warn all")
include(CheckCCompilerFlag)
include(CheckCXXCompilerFlag)
include(CheckFortranCompilerFlag)
function(set_compiler_flag _result _lang)
# build a list of flags from the arguments
set(_list_of_flags)
# also figure out whether the function
# is required to find a flag
set(_flag_is_required FALSE)
foreach(_arg IN ITEMS ${ARGN})
string(TOUPPER "${_arg}" _arg_uppercase)
if(_arg_uppercase STREQUAL "REQUIRED")
set(_flag_is_required TRUE)
else()
list(APPEND _list_of_flags "${_arg}")
endif()
endforeach()
set(_flag_found FALSE)
# loop over all flags, try to find the first which works
foreach(flag IN ITEMS ${_list_of_flags})
unset(_${flag}_works CACHE)
if(_lang STREQUAL "C")
check_c_compiler_flag("${flag}" _${flag}_works)
elseif(_lang STREQUAL "CXX")
check_cxx_compiler_flag("${flag}" _${flag}_works)
elseif(_lang STREQUAL "Fortran")
check_Fortran_compiler_flag("${flag}" _${flag}_works)
else()
message(FATAL_ERROR "Unknown language in set_compiler_flag: ${_lang}")
endif()
# if the flag works, use it, and exit
# otherwise try next flag
if(_${flag}_works)
set(${_result} "${flag}" PARENT_SCOPE)
set(_flag_found TRUE)
break()
endif()
endforeach()
# raise an error if no flag was found
if(_flag_is_required AND NOT _flag_found)
message(FATAL_ERROR "None of the required flags were supported")
endif()
endfunction()
|
