diff mbox

Make -Wint-in-bool-context warn on suspicious shift ops

Message ID AM4PR0701MB216271B9FB40495B4D5AF6FDE4D30@AM4PR0701MB2162.eurprd07.prod.outlook.com
State New
Headers show

Commit Message

Bernd Edlinger Oct. 18, 2016, 5:04 p.m. UTC 
Hi,

this restricts the -Wint-in-bool-context warning to signed shifts,
to reduce the number of false positives Markus reported yesterday.

Bootstrap and reg-testing on x86_64-pc-linux-gnu was fine.
Is it OK for trunk?


Thanks
Bernd.

Comments

Joseph Myers Oct. 18, 2016, 5:05 p.m. UTC | #1 
On Tue, 18 Oct 2016, Bernd Edlinger wrote:

> Hi,
> 
> this restricts the -Wint-in-bool-context warning to signed shifts,
> to reduce the number of false positives Markus reported yesterday.

This patch seems to be missing testcases (that warned before the patch 
and don't warn after it).
diff mbox

Patch

2016-10-17  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* c-common.c (c_common_truthvalue_conversion): Warn only for signed
	integer shift ops in boolean context.

Index: gcc/c-family/c-common.c
===================================================================
--- gcc/c-family/c-common.c	(revision 241270)
+++ gcc/c-family/c-common.c	(working copy)
@@ -3328,8 +3328,10 @@ 
 					       TREE_OPERAND (expr, 0));
 
     case LSHIFT_EXPR:
-      warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context,
-		  "<< in boolean context, did you mean '<' ?");
+      if (TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
+	  && !TYPE_UNSIGNED (TREE_TYPE (expr)))
+	warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context,
+		    "<< in boolean context, did you mean '<' ?");
       break;
 
     case COND_EXPR: