1 files changed, 79 insertions, 0 deletions
diff --git a/Modules/Internal/CheckCompilerFlag.cmake b/Modules/Internal/CheckCompilerFlag.cmake
new file mode 100644
index 0000000..f790d87
--- /dev/null
+++ b/Modules/Internal/CheckCompilerFlag.cmake
@@ -0,0 +1,79 @@
+# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
+
+include_guard(GLOBAL)
+include(Internal/CheckSourceCompiles)
+include(CMakeCheckCompilerFlagCommonPatterns)
+
+cmake_policy(PUSH)
+cmake_policy(SET CMP0054 NEW) # if() quoted variables not dereferenced
+cmake_policy(SET CMP0057 NEW) # if() supports IN_LIST
+
+function(CMAKE_CHECK_COMPILER_FLAG _lang _flag _var)
+
+  if(_lang STREQUAL C)
+    set(_lang_src "int main(void) { return 0; }")
+    set(_lang_fail_regex FAIL_REGEX "command[ -]line option .* is valid for .* but not for C")
+  elseif(_lang STREQUAL CXX)
+    set(_lang_src "int main() { return 0; }")
+    set(_lang_fail_regex FAIL_REGEX "command[ -]line option .* is valid for .* but not for C\\+\\+")
+    elseif(_lang STREQUAL CUDA)
+    set(_lang_src "__host__ int main() { return 0; }")
+    set(_lang_fail_regex FAIL_REGEX "command[ -]line option .* is valid for .* but not for C\\+\\+" # Host GNU
+                         FAIL_REGEX "argument unused during compilation: .*") # Clang
+  elseif(_lang STREQUAL Fortran)
+    set(_lang_src "       program test\n       stop\n       end program")
+    set(_lang_fail_regex FAIL_REGEX "command[ -]line option .* is valid for .* but not for Fortran")
+  elseif(_lang STREQUAL OBJC)
+    set(_lang_src [=[
+#ifndef __OBJC__
+#  error "Not an Objective-C compiler"
+#endif
+int main(void) { return 0; }]=])
+    set(_lang_fail_regex FAIL_REGEX "command[ -]line option .* is valid for .* but not for Objective-C" # GNU
+                         FAIL_REGEX "argument unused during compilation: .*") # Clang
+  elseif(_lang STREQUAL OBJCXX)
+    set(_lang_src [=[
+#ifndef __OBJC__
+#  error "Not an Objective-C++ compiler"
+#endif
+int main(void) { return 0; }]=])
+    set(_lang_fail_regex FAIL_REGEX "command[ -]line option .* is valid for .* but not for Objective-C\\+\\+" # GNU
+                         FAIL_REGEX "argument unused during compilation: .*") # Clang
+  elseif(_lang STREQUAL ISPC)
+    set(_lang_src "float func(uniform int32, float a) { return a / 2.25; }")
+  else()
+    message (SEND_ERROR "check_compiler_flag: ${_lang}: unknown language.")
+    return()
+  endif()
+
+  get_property (_supported_languages GLOBAL PROPERTY ENABLED_LANGUAGES)
+  if (NOT _lang IN_LIST _supported_languages)
+    message (SEND_ERROR "check_compiler_flag: ${_lang}: needs to be enabled before use.")
+    return()
+  endif()
+
+  set(CMAKE_REQUIRED_DEFINITIONS ${_flag})
+
+  # Normalize locale during test compilation.
+  set(_locale_vars LC_ALL LC_MESSAGES LANG)
+  foreach(v IN LISTS _locale_vars)
+    set(_locale_vars_saved_${v} "$ENV{${v}}")
+    set(ENV{${v}} C)
+  endforeach()
+
+  check_compiler_flag_common_patterns(_common_patterns)
+  cmake_check_source_compiles(${_lang}
+    "${_lang_src}"
+    ${_var}
+    ${_lang_fail_regex}
+    ${_common_patterns}
+    )
+
+  foreach(v IN LISTS _locale_vars)
+    set(ENV{${v}} ${_locale_vars_saved_${v}})
+  endforeach()
+  set(${_var} "${${_var}}" PARENT_SCOPE)
+endfunction ()
+
+cmake_policy(POP)