Neil Williams wrote: > On Thu, 2008-05-22 at 01:12 -0400, Felipe Sateler wrote: >> Hi. Csound, a package I maintain, supports enabling a set of gcc >> optimizations via a build option. Code generated with those options can be >> significantly faster (I've seen improvements of over 2x). However, this >> option means adding a -mtune option to gcc. Obviously, the only sane option >> for a debian package is -mtune=generic (which is apparently only available on >> x86 and amd64). However I read in the info pages for gcc: >> >> > Produce code optimized for the most common IA32/AMD64/EM64T processors. >> >> Does this mean that setting -mtune=generic is the same as setting -mtune to >> the most popular processor? If so, can/should I use that option? > > Only for the supported architectures or you'll get a build failure on > ARM, powerpc, mips, sparc etc.
Of course. I already noted that it was only available on x86 and amd64. > > To check the arch, always test against the HOST architecture. Native > builds set HOST == BUILD but if the package is ever cross-built, your > debian/rules must allow building an ARM package on amd64 (HOST=ARM, > BUILD=amd64) and *NOT* enable -mtune. > > DEB_HOST_ARCH_CPU=... -qDEB_HOST_ARCH_CPU) > > This holds true for any architecture-specific checks in any package - > always, always check the HOST value - BUILD is almost always the wrong > variable to use. I think csound is unlikely to be cross-built. Sound synthesis is a pretty cpu-intensive task. If I enable it then I should only enable it on the appropriate environments. However there is still the question: is it reasonable to enable this option on supported archs? -- Felipe Sateler -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
