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From: "glisse at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/60819] dse1 removing not-dead insn (aliasing issue?)
Date: Fri, 11 Apr 2014 12:27:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60819

--- Comment #5 from Marc Glisse <glisse at gcc dot gnu.org> ---
typedef int v2si __attribute__((vector_size (8),may_alias));
typedef short v4hi __attribute__((vector_size (8),may_alias));
int f (v2si __A, int __N)
{ return (*(v4hi*)&__A)[__N]; }

also fails.

Reading the documentation of may_alias, I have the impression that this example
is doing exactly what may_alias is supposed to allow, no?