$OpenBSD: patch-gcc_config_openbsd_h,v 1.2 2012/10/07 20:09:45 landry Exp $
--- gcc/config/openbsd.h.orig	Tue Oct 18 01:31:25 2011
+++ gcc/config/openbsd.h	Sat Oct  6 12:46:28 2012
@@ -109,9 +109,9 @@ while (0)
    This two-stage defines makes it easy to pick that for targets that
    have subspecs.  */
 #ifdef CPP_CPU_SPEC
-#define OBSD_CPP_SPEC "%(cpp_cpu) %{posix:-D_POSIX_SOURCE} %{pthread:-D_POSIX_THREADS}"
+#define OBSD_CPP_SPEC "%(cpp_cpu) %{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
 #else
-#define OBSD_CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_POSIX_THREADS}"
+#define OBSD_CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
 #endif
 
 #undef LIB_SPEC
@@ -279,6 +279,16 @@ do {									 \
 #endif
 
 /* Storage layout.  */
+
+/*
+ * Disable the use of unsafe builtin functions, (strcat, strcpy, stpcpy),
+ * making them easier to spot in the object files.
+ */
+#define NO_UNSAFE_BUILTINS
+
+/* The system headers on OpenBSD are C++-aware.  */
+#undef NO_IMPLICIT_EXTERN_C
+#define NO_IMPLICIT_EXTERN_C
 
 
 #define HAVE_ENABLE_EXECUTE_STACK
