Bug 10962 – mjpegtools fails with -O3

• Product: Gentoo Linux
• Status: RESOLVED FIXED

[Description Justin 2002-11-19 10:47:21 UTC]

I encountered this problem when tryting to compile mjpegtools using GCC 3.2
under gentoo-1.4_rc1. When compiling certain packages (mjpegtools, and probably
a few others) with "agressive optimizations", the build fails. Take a look at
https://listman.redhat.com/pipermail/limbo-list/2002-July/000629.html . I know
some packages disable high optimizations within the ebuild itself....perhaps
this should be done for mjpegtools as well.

Trying to build mjpegtools-1.6.0-r4 with:

CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

fails. But this:

CFLAGS="-mcpu=i686 -march=i686 -O2"

works fine. 

Has anyone else experienced this problem?

-Justin

[Comment 1 Matthew Kennedy (RETIRED) 2002-11-19 16:29:11 UTC]

vapier, title change wasn't necessary. it in fact works with -O3
-march=pentium3 -pipe

[Comment 2 Matthew Kennedy (RETIRED) 2002-11-19 16:31:04 UTC]

is it the -fomit-frame-pointer which killed it for you, or was it
-march=pentium4?

[Comment 3 Justin 2002-11-19 17:58:33 UTC]

Oops...it turns out that the -march=pentium4 was the cause. Works fine with:

CFLAGS="-march=i686 -O3 -pipe -fomit-frame-pointer"

-Justin

[Comment 4 Matthew Kennedy (RETIRED) 2002-11-19 19:52:33 UTC]

should be fixed in -r5. thanks for the bug report.

[Comment 5 Justin 2002-11-19 23:38:40 UTC]

My first "RESOLVED FIXED" bug report :-) . I'm glad to be of help.

-Justin

[Comment 6 Matthew Kennedy (RETIRED) 2002-11-20 01:59:35 UTC]

you're welcome! this class of bug report is fairly common. we use the
flag-o-matic elcass (in /usr/portage/eclass) to crop a users CFLAGS to stuff we
know actually works. (just in case you're curious)