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Re: [PATCH] Make memset in calloc a tail call.

From: Mike Frysinger <vapier at gentoo dot org>
To: libc-alpha at sourceware dot org
Cc: Andrew Pinski <pinskia at gmail dot com>, OndÅej BÃlka <neleai at seznam dot cz>
Date: Wed, 27 Nov 2013 03:36:17 -0500
Subject: Re: [PATCH] Make memset in calloc a tail call.
Authentication-results: sourceware.org; auth=none
References: <20131107203149 dot GA21816 at domone> <CA+=Sn1=ufrpY88vMS6Y9ZmA+P1VjHJ9Bqh4CWkpLfoEdVWr64Q at mail dot gmail dot com>

On Thursday 07 November 2013 15:39:46 Andrew Pinski wrote:
> On Thu, Nov 7, 2013 at 12:31 PM, OndÅej BÃlka <neleai@seznam.cz> wrote:
> > Hi, after reading a calloc code I found that we do not return memset
> > value. Unless compiler can recognize that memset result and return value
> > are same it will be used as normal call but a tail call is faster.
> 
> It can and does in 4.8 and above but that is after the tail call
> optimization happens.

i wonder if we should merge OndÅej's fix with a comment like "we can drop this 
after we require gcc-4.8+.  seems like an easy win for older compilers for no 
overhead on our side.
-mike

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References:
- [PATCH] Make memset in calloc a tail call.
  - From: OndÅej BÃlka
- Re: [PATCH] Make memset in calloc a tail call.
  - From: Andrew Pinski

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