* [PATCH] Fix -Wunused-but-set-* in C with stmt expression and array in it (PR c/50179)
@ 2011-08-26 4:27 Jakub Jelinek
2011-08-26 14:44 ` Joseph S. Myers
0 siblings, 1 reply; 2+ messages in thread
From: Jakub Jelinek @ 2011-08-26 4:27 UTC (permalink / raw)
To: Joseph S. Myers; +Cc: gcc-patches
Hi!
As the following testcase shows, if the last expression in statement
expression is array, mark_exp_read wasn't called on it.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux,
ok for trunk/4.6?
2011-08-26 Jakub Jelinek <jakub@redhat.com>
PR c/50179
* c-typeck.c (c_process_expr_stmt): Skip over nops and
call mark_exp_read even if exprv is ADDR_EXPR.
* c-c++-common/Wunused-var-14.c: New test.
--- gcc/c-typeck.c.jj 2011-08-18 08:36:00.000000000 +0200
+++ gcc/c-typeck.c 2011-08-25 12:08:02.000000000 +0200
@@ -9109,7 +9109,11 @@ c_process_expr_stmt (location_t loc, tre
exprv = expr;
while (TREE_CODE (exprv) == COMPOUND_EXPR)
exprv = TREE_OPERAND (exprv, 1);
- if (DECL_P (exprv) || handled_component_p (exprv))
+ while (CONVERT_EXPR_P (exprv))
+ exprv = TREE_OPERAND (exprv, 0);
+ if (DECL_P (exprv)
+ || handled_component_p (exprv)
+ || TREE_CODE (exprv) == ADDR_EXPR)
mark_exp_read (exprv);
/* If the expression is not of a type to which we cannot assign a line
--- gcc/testsuite/c-c++-common/Wunused-var-14.c.jj 2011-08-25 12:04:39.000000000 +0200
+++ gcc/testsuite/c-c++-common/Wunused-var-14.c 2011-08-25 12:04:34.000000000 +0200
@@ -0,0 +1,13 @@
+/* PR c/50179 */
+/* { dg-options "-Wunused" } */
+/* { dg-do compile } */
+
+void bar (int, ...);
+
+char *
+foo (void)
+{
+ bar (1, (__extension__ ({ static char b[2]; b[0] = 1; b; })));
+ bar (1, ({ static char c[2]; c[0] = 1; c; }));
+ return ({ static char d[2]; d[0] = 1; d; });
+}
Jakub
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [PATCH] Fix -Wunused-but-set-* in C with stmt expression and array in it (PR c/50179)
2011-08-26 4:27 [PATCH] Fix -Wunused-but-set-* in C with stmt expression and array in it (PR c/50179) Jakub Jelinek
@ 2011-08-26 14:44 ` Joseph S. Myers
0 siblings, 0 replies; 2+ messages in thread
From: Joseph S. Myers @ 2011-08-26 14:44 UTC (permalink / raw)
To: Jakub Jelinek; +Cc: gcc-patches
On Fri, 26 Aug 2011, Jakub Jelinek wrote:
> Hi!
>
> As the following testcase shows, if the last expression in statement
> expression is array, mark_exp_read wasn't called on it.
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux,
> ok for trunk/4.6?
OK.
--
Joseph S. Myers
joseph@codesourcery.com
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2011-08-26 14:25 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-08-26 4:27 [PATCH] Fix -Wunused-but-set-* in C with stmt expression and array in it (PR c/50179) Jakub Jelinek
2011-08-26 14:44 ` Joseph S. Myers
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).