Index: test/support/test_macros.h
===================================================================
--- test/support/test_macros.h
+++ test/support/test_macros.h
@@ -22,6 +22,12 @@
 #define TEST_HAS_FEATURE(X) 0
 #endif
 
+#ifdef __has_include
+#define TEST_HAS_INCLUDE(X) __has_include(X)
+#else
+#define TEST_HAS_INCLUDE(X) 0
+#endif
+
 #ifdef __has_extension
 #define TEST_HAS_EXTENSION(X) __has_extension(X)
 #else
@@ -63,7 +69,7 @@
 #endif
 
 // Attempt to deduce GCC version
-#if defined(_LIBCPP_VERSION) && __has_include(<features.h>)
+#if defined(_LIBCPP_VERSION) && TEST_HAS_INCLUDE(<features.h>)
 #include <features.h>
 #define TEST_HAS_GLIBC
 #define TEST_GLIBC_PREREQ(major, minor) __GLIBC_PREREQ(major, minor)