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Re: [PATCH] Fix UB in expmed.c (PR middle-end/61903)

From: Jeff Law <law at redhat dot com>
To: Marek Polacek <polacek at redhat dot com>, GCC Patches <gcc-patches at gcc dot gnu dot org>
Date: Fri, 29 Aug 2014 14:08:04 -0600
Subject: Re: [PATCH] Fix UB in expmed.c (PR middle-end/61903)
Authentication-results: sourceware.org; auth=none
References: <20140825192135 dot GL15033 at redhat dot com>

On 08/25/14 13:21, Marek Polacek wrote:

The following ought to fix two spots where an undefined behavior
can occur when compiling pr28045.c with instrumented compiler.
It does so by changing the type of V to an unsigned HOST_WIDE_INT
and performing the shift on unsigned HOST_WIDE_INT.
Hopefully it doesn't break anything...

Bootstrapped/regtested on x86_64-linux, ok for trunk?

2014-08-25  Marek Polacek  <polacek@redhat.com>

	PR middle-end/61903
	* expmed.c (store_fixed_bit_field_1): Shift UHWI 1 instead of HWI 1.
	Change the type of V to unsigned HOST_WIDE_INT.

OK.
Jeff

References:
- [PATCH] Fix UB in expmed.c (PR middle-end/61903)
  - From: Marek Polacek

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