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Re: Weird warning when building gcc
- From: Jeff Law <law at redhat dot com>
- To: nick <xerofoify at gmail dot com>, gcc at gcc dot gnu dot org
- Date: Sat, 23 Sep 2017 10:05:33 -0600
- Subject: Re: Weird warning when building gcc
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On 09/22/2017 08:25 PM, nick wrote:
> Greetings All,
>
> I am wondering if this is a warning worth looking into or is it just another false postive:
>
> /home/nick/gcc/gcc/combine.c:1316:8: warning: ‘prev’ may be used uninitialized in this function [-Wmaybe-uninitialized]
> if ((next = try_combine (insn, prev, NULL, NULL,
>
> Maybe it's just me being new to the project but is the code for that literally or also identical between this and the
> one where CC0 register is directly used.
Looks like a false positive to me. Without more details (host, target,
flags, cpp output) I can't be 100% sure why it triggers though.
Flow sensitive warnings such as this are very sensitive to a variety of
low level target and IL details.
Jeff