Perhaps I don't get you point, but I get the same with:
int main()
{
rtx rt;
put_code(&rt, (short)5);
printf("gen_rtx, code=%d\n", (int)rt.code);
}
/Kjeld
-----Original Message-----
From: owner-linux-mips@oss.sgi.com
[mailto:owner-linux-mips@oss.sgi.com]On Behalf Of H . J . Lu
Sent: 13. september 2001 17:11
To: Kjeld Borch Egevang
Cc: linux-mips@oss.sgi.com
Subject: Re: Error in gcc version 2.96 20000731
On Thu, Sep 13, 2001 at 04:15:10PM +0200, Kjeld Borch Egevang wrote:
> Hi all.
>
> I discovered an optimization error in the current gcc for MIPS.
>
> When I compile the code below with -O2 it clears the code-field just
> after setting it. The instructions are mixed up. It works fine with -O1
> and -O0.
>
> If the "//" is removed in front of the first printf, it works too.
>
The code isn't ISO C. You cannot declare something as short and then
access it as int. On x86:
# gcc alias.c -O
put_code after, code=5 5
gen_rtx, code=5
# gcc alias.c -O2
put_code after, code=5 0
gen_rtx, code=0
On mips,
# gcc alias.c -O
put_code after, code=5 5
gen_rtx, code=5
# gcc alias.c -O2
put_code after, code=5 5
gen_rtx, code=0
You can fix the code or add -fno-strict-aliasing
# gcc alias.c -O2 -fno-strict-aliasing
put_code after, code=5 5
gen_rtx, code=5
H.J.
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