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From: Jakub Jelinek <jakub@redhat.com>
To: gcc-patches@gcc.gnu.org
Subject: [committed] Fix up pr51628-10.c testcase (PR target/88682)
Date: Wed, 16 Jan 2019 14:22:00 -0000	[thread overview]
Message-ID: <20190116142157.GU30353@tucnak> (raw)

Hi!

This testcase violates aliasing and so is "miscompiled" e.g. on powerpc64
or aarch64 at -O2.  Fixed thusly, tested on powerpc64-linux, committed to
trunk as obvious.

2019-01-16  Jakub Jelinek  <jakub@redhat.com>

	PR c/51628
	PR target/88682
	* c-c++-common/pr51628-10.c (unaligned_int128_t): Add
	may_alias attribute.

--- gcc/testsuite/c-c++-common/pr51628-10.c.jj	2018-12-21 00:40:49.048937834 +0100
+++ gcc/testsuite/c-c++-common/pr51628-10.c	2019-01-16 15:15:51.515279138 +0100
@@ -11,7 +11,7 @@ struct pair_t
 typedef struct unaligned_int128_t_
 {
   __int128_t value;
-} __attribute__((packed)) unaligned_int128_t;
+} __attribute__((packed, may_alias)) unaligned_int128_t;
 
 struct pair_t p = {0, 1};
 unaligned_int128_t *addr = (unaligned_int128_t *) &p.i;

	Jakub

                 reply	other threads:[~2019-01-16 14:22 UTC|newest]

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