2009/9/25 Chris Adams:
Having different packages (that may conflict with each other) means you
can't easily switch between versions, and if you chose the wrong version
(or move a hard drive to a different box), your programs crash
That's exactly why
had been reported. The default atlas.i586 package on F11 had been built with SSE support and thus crashed on a generic P6 which was supposed to (over)-fulfill the minimum requirements for F11 (and probably those of F12, too)
It could not even be removed from the system although blas/lapack were installed as well, because packages like octave actually require it! Thus it is not simply an optional performance optimized package installed by people doing numerics in order to supersede the standard blas/lapack packages. I consider it thus intelligible to use a hierarchy
atlas < atlas-sse < atlas-sse2
the first one being installed by default and and not using SSEx at all. Also note, that otherwise, one could argue that all x86 packages (including blas/lapack) should be built using SSEx as well, but this discussion had already taken place on this list a few months ago .. .
(Likewise, the default x86_64 package is currently called
atlas [ < atlas-sse3 < ... ]
and is using SSE2 by default as expected for all x86_64 packages. Higher optimized versions enabling SSE3, SSE4.x which do not exist yet would follow the same naming scheme.).