Bug 14317 – __xpg_strerror_r not fully optimized

Bug 14317 - __xpg_strerror_r not fully optimized


Summary:	__xpg_strerror_r not fully optimized

Status:	RESOLVED FIXED

Product:	glibc
Classification:	Unclassified
Component:	libc
Version:	2.16

Importance:	P1 normal
Target Milestone:	2.18
Assigned To:	Andreas Jaeger

URL:
Keywords:

Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2012-06-30 16:04 UTC by Bruno Haible
Modified:	2012-12-27 21:42 UTC (History)
CC List:	3 users (show)

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Attachments
proposed fix (1.67 KB, patch) 2012-06-30 16:08 UTC, Bruno Haible	Details \| Diff
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Description Bruno Haible 2012-06-30 16:04:52 UTC

The implementation of __xpg_strerror_r spends time doing an strlen call,
and then potentially returning before the value is actually used.

This can be optimized.

Comment 1 Bruno Haible 2012-06-30 16:08:34 UTC

Created attachment 6502 [details]
proposed fix

Comment 2 Carlos O'Donell 2012-07-24 04:10:04 UTC

Bruno,

Fold the copyright years together e.g. 1991-2012.

If you haven't posted this to libc-alpha, please do and I'll ack.

This looks like a straight forward and useful optimization.

Comment 3 Andreas Jaeger 2012-12-01 17:05:12 UTC

I cleaned up the patch and send it to libc-alpha myself.

Comment 4 Andreas Jaeger 2012-12-03 15:38:46 UTC

Targeting for 2.18 now.

Comment 5 Andreas Jaeger 2012-12-27 21:42:42 UTC

Committed for glibc 2.18:

commit 7fffbdfff7d39cec0783e5b9381fa4093484c235
Author: 2012-12-27 Bruno Haible <bruno@clisp.org>
Date:   Thu Dec 27 22:37:39 2012 +0100

    BZ#14317: Optimze __xpg_strerror_r
    
    [BZ #14317]
    * string/xpg-strerror.c (__xpg_strerror_r): Optimize, call
    strlen only if needed.

thanks for the patch!