diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index ec196780fe2..2809e928652 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2000-07-17  Chip Salzenberg  <chip@valinux.com>
+
+	* c-common.c (shorten_compare): Quiet warnings about unsigned
+	comparisons with zero when they occur in a system header.
+
 2000-07-17  Joseph S. Myers  <jsm28@cam.ac.uk>
 
 	* c-common.c (check_format_info): Do not make a pedantic objection
diff --git a/gcc/c-common.c b/gcc/c-common.c
index 8a8103bbb7a..1e31b29e9f1 100644
--- a/gcc/c-common.c
+++ b/gcc/c-common.c
@@ -2833,7 +2833,7 @@ shorten_compare (op0_ptr, op1_ptr, restype_ptr, rescode_ptr)
 		 are requested.  However, if OP0 is a constant that is
 		 >= 0, the signedness of the comparison isn't an issue,
 		 so suppress the warning.  */
-	      if (extra_warnings
+	      if (extra_warnings && !in_system_header
 		  && ! (TREE_CODE (primop0) == INTEGER_CST
 			&& ! TREE_OVERFLOW (convert (signed_type (type),
 						     primop0))))
@@ -2842,7 +2842,7 @@ shorten_compare (op0_ptr, op1_ptr, restype_ptr, rescode_ptr)
 	      break;
 
 	    case LT_EXPR:
-	      if (extra_warnings
+	      if (extra_warnings && !in_system_header
 		  && ! (TREE_CODE (primop0) == INTEGER_CST
 			&& ! TREE_OVERFLOW (convert (signed_type (type),
 						     primop0))))