#endif
#endif
-// Attempt to deduce GCC version
-#if defined(_LIBCPP_VERSION) && __has_include(<features.h>)
+// Attempt to deduce the GLIBC version
+#if (defined(__has_include) && __has_include(<features.h>)) || \
+ defined(__linux__)
#include <features.h>
#define TEST_HAS_GLIBC
#define TEST_GLIBC_PREREQ(major, minor) __GLIBC_PREREQ(major, minor)
# define TEST_HAS_TIMESPEC_GET
# elif defined(__linux__)
# if !defined(_LIBCPP_HAS_MUSL_LIBC)
-# if _LIBCPP_GLIBC_PREREQ(2, 17)
+# if defined(TEST_GLIBC_PREREQ) && TEST_GLIBC_PREREQ(2, 17)
# define TEST_HAS_TIMESPEC_GET
# define TEST_HAS_C11_FEATURES
# endif