CMake/Modules/CMakeCXXCompilerId.cpp.in
Brad King c3dc8935ee Make C and C++ default dialect detection robust to advanced optimizations
In commit v3.4.0-rc1~71^2 (Project: Determine default language dialect
for the compiler, 2015-09-15) we added an "INFO:..." string to the
compiler id detection binary.  The value can be optimized out of the
compiler id binary unless we force it to be included by making the
program behavior depend on it at runtime.  Add references to the value
as we do for the other info strings already.

Gentoo-Issue: https://bugs.gentoo.org/show_bug.cgi?id=565744
2015-11-18 10:12:25 -05:00

56 lines
1.5 KiB
C++

/* This source file must have a .cpp extension so that all C++ compilers
recognize the extension without flags. Borland does not know .cxx for
example. */
#ifndef __cplusplus
# error "A C compiler has been selected for C++."
#endif
@CMAKE_CXX_COMPILER_ID_CONTENT@
/* Construct the string literal in pieces to prevent the source from
getting matched. Store it in a pointer rather than an array
because some compilers will just produce instructions to fill the
array rather than assigning a pointer to a static array. */
char const* info_compiler = "INFO" ":" "compiler[" COMPILER_ID "]";
#ifdef SIMULATE_ID
char const* info_simulate = "INFO" ":" "simulate[" SIMULATE_ID "]";
#endif
#ifdef __QNXNTO__
char const* qnxnto = "INFO" ":" "qnxnto[]";
#endif
@CMAKE_CXX_COMPILER_ID_PLATFORM_CONTENT@
@CMAKE_CXX_COMPILER_ID_ERROR_FOR_TEST@
const char* info_language_dialect_default = "INFO" ":" "dialect_default["
#if __cplusplus >= 201402L
"14"
#elif __cplusplus >= 201103L
"11"
#else
"98"
#endif
"]";
/*--------------------------------------------------------------------------*/
int main(int argc, char* argv[])
{
int require = 0;
require += info_compiler[argc];
require += info_platform[argc];
#ifdef COMPILER_VERSION_MAJOR
require += info_version[argc];
#endif
#ifdef SIMULATE_ID
require += info_simulate[argc];
#endif
#ifdef SIMULATE_VERSION_MAJOR
require += info_simulate_version[argc];
#endif
require += info_language_dialect_default[argc];
(void)argv;
return require;
}