Bug 143895

Summary:	perl, libperl gets screwed by -fsched2-use-superblocks; a case for flag-o-matic?
Product:	Gentoo Linux	Reporter:	sg313 <sg313d>
Component:	[OLD] Core system	Assignee:	Gentoo Perl team <perl>
Status:	RESOLVED FIXED
Severity:	enhancement	CC:	jakub
Priority:	Highest
Version:	2006.0
Hardware:	x86
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	Filters -fsched2-use-superblocks for perl Filters -fsched2-use-superblocks for libperl

Description sg313 2006-08-14 09:47:00 UTC

perl and libperl don't like the optimization flag -fsched2-use-superblocks in conjunction with -O2 or higher on gcc-4.1.1. 
This causes perl 'require vX.Y.Z' to fail for versions ending with .0 (Z=0),
for example a perl-5.8.8 installation exit with an error from 
perl -e 'require v5.6.0'; 
On gcc-3.4.6 these malfunctions couldn't be observed.

Description:
The optimization damages loop code in str_to_version. As a consequence the command >>perl -e require 'vX.Y.0'<< will fail for any values of X,Y;
This seems to be version of a (well) known bug on gcc-bugzilla. They closed
it as wontfix.
See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=323 for details.
If are convinced that this is a another bug, feel free to file it at
the gcc-bugzilla.

Steps to reproduce:
1. Compile libperl/perl >= 5.8 with gcc-4.1.1, -O2 & -fsched2-use-superblocks.
2. perl -e 'require 5.6.0' -> Will abort with error (!)

Proposed solution:
This can be easyly circumvented by using flag-o-matic to  strip -fsched2-use-superblocks from CFLAGS.
Patches for perl and libperl ebuilds are attached.

Comment 1 sg313 2006-08-14 09:51:42 UTC

Created attachment 94253 [details, diff]
Filters -fsched2-use-superblocks for perl

s.o.

Comment 2 sg313 2006-08-14 09:52:32 UTC

Created attachment 94254 [details, diff]
Filters -fsched2-use-superblocks for libperl

s.o.

Comment 3 Jakub Moc (RETIRED) gentoo-dev

2006-08-14 10:23:34 UTC

Quite frankly, we really have better things to do that to filter whatever ultraweird flag that someone has stuck into his flags for whatever reason. How about that you filter it yourself?

Comment 4 sg313 2006-08-14 10:41:32 UTC

The report was not meant to be an offense. Discard it if you want;
I just wanted to share the solution.

Comment 5 Christian Hartmann (RETIRED) gentoo-dev

2006-08-15 06:48:59 UTC

Fixed in cvs.

Comment 6 sg313 2006-08-15 09:23:41 UTC

Thanks!