1 files changed, 9 insertions, 0 deletions
diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index 5880fe9c5e..78c419244a 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -123,6 +123,15 @@
 # define __attribute_malloc__ /* Ignore */
 #endif
 
+/* At some point during the gcc 2.96 development the `pure' attribute
+   for functions was introduced.  We don't want to use it unconditionally
+   (although this would be possible) since it generates warnings.  */
+#if __GNUC_PREREQ (2,96)
+# define __attribute_pure__ __attribute__ ((__pure__))
+#else
+# define __attribute_pure__ /* Ignore */
+#endif
+
 /* It is possible to compile containing GCC extensions even if GCC is
    run in pedantic mode if the uses are carefully marked using the
    `__extension__' keyword.  But this is not generally available before