diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index ccb15b3f1e8..79c7c842378 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+Wed Sep  9 23:00:48 1998  Nathan Sidwell  <nathan@acm.org>
+
+	* c-lex.c (real_yylex): Don't warn about long long constants if 
+	we're allowing long long
+
 Wed Sep  9 21:58:41 1998  Bernd Schmidt <crux@pool.informatik.rwth-aachen.de>
 
 	* except.h (current_function_eh_stub_label): Declare.
diff --git a/gcc/c-lex.c b/gcc/c-lex.c
index 2f225282e7e..a90d3b58f11 100644
--- a/gcc/c-lex.c
+++ b/gcc/c-lex.c
@@ -1646,7 +1646,7 @@ yylex ()
 		      {
 			if (spec_long_long)
 			  error ("three `l's in integer constant");
-			else if (pedantic)
+			else if (pedantic && ! in_system_header && warn_long_long)
 			  pedwarn ("ANSI C forbids long long integer constants");
 			spec_long_long = 1;
 		      }