Kurt Roeckx <[EMAIL PROTECTED]> writes: > On Sat, Apr 26, 2008 at 07:05:17PM -0700, Russ Allbery wrote: >> gnubg supports optionally building with SSE support for increased speed in >> the analytical engine. I have to date kept this disabled to not generate >> binaries that might not run on all otherwise-supported Debian systems. >> >> However, a user mentioned that he thinks all chips that fall into the >> amd64 architecture have SSE and hence adding -msse would be safe for the >> amd64 build. Is that correct? > > There is no need to enable -msse on amd64. It has always been on by > default. > >> And in general are there any guidelines >> about things like this? I assume that using -msse for the i386 build is >> still out since we still support 486 chips. > > If you want to have different optimizations depending on the cpu, > there are a two options I know of: > - When you hace shared libraries you can put them in directories like > /usr/lib/i686/sse/. The dynamic linker whould pick it up for > you in that case. (I have no idea if it looks at i686/sse or not, > but it looks at various other dirs, I can't find documentation for it.)
It doesn't. But one could add /usr/lib/sse via /etc/ld.so.conf.d/package-sse when package-sse gets installed with some check that the system actualy does have sse support. > - Use runtime detection of the cpu and select the best option yourself. Always better. Someone might want to share /usr between systems with and without sse. MfG Goswin -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]