I updated xorg-server to 1.4-r1 (from 1.3.0.0). =x11-libs/pixman-0.9.5 is a dependency and was installed. The new xserver would only run 'simple' applications, such as xdaliclock, xterm and twm. Other applications would cause the xserver to crash, and a signal 4 AKA SIGILL (illegal instruction) would be reported in /var/log/Xorg.0.log. I discovered =x11-libs/pixman-0.9.5 *appends* -msse to CFLAGS when compiling, even if your processor has MMX, but not SSE support (like my old AMD Duron), and you use -mmmx, but not -msse. The library seems to have MMX and SSE optimisations, and I believe it's supposed to support either or both. However, the configure script is very inflexible and enables MMX (-mmmx) and SSE (-msse) together, despite your actual CFLAGS. I managed to compile the pixman ebuild without SSE instructions, and my xserver appears to be working well now. In the last few hours, a bugfix has been reported in the Debian bug report: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=442829 However, the fixed Debian package hasn't appeared on the FTP server yet, so I can't tell whether it's a workaround or full fix. The package should appear here: http://ftp.debian.org/debian/pool/main/p/pixman/ freedesktop.org has a similar bug report, but it doesn't have any useful details yet: https://bugs.freedesktop.org/show_bug.cgi?id=12398 Interestingly, lots of recent commit summaries at the pixman git repository involve the MMX support, but the posts there are a bit cryptic: http://gitweb.freedesktop.org/?p=pixman.git;a=shortlog Ideally, the package should compile as per your CFLAGS, building MMX support when -mmmx is present, and SSE support when -msse is present. However, I'm not familiar with the build tools and the library seems to be in a state of flux now anyway.
This is a duplicate of 192048.
While I was writing this post comment #1 was posted: http://bugs.gentoo.org/show_bug.cgi?id=193138#c1 Sorry for the duplicate. I did search around for appropriate bugs. I don't know how I missed it. Maybe stale web caches? The bug report which I've accidentally duplicated: http://bugs.gentoo.org/show_bug.cgi?id=192048 ... The debian fix has appeared. It appears they workaround the bug by removing the SSE CFLAG (-msse) from the makefiles, as can be seen here: http://ftp.debian.org/debian/pool/main/p/pixman/pixman_0.9.5-2.diff.gz I posted to the aforementioned freedesktop.org bug: https://bugs.freedesktop.org/show_bug.cgi?id=12398#c6 Also, I found an even more appropriate freedeskop.org bug report, which anticipates the bug on 20/7/2007!: https://bugs.freedesktop.org/show_bug.cgi?id=4706#c4
*** This bug has been marked as a duplicate of bug 192048 ***
