Hi, A bug[1] was filed about a build failure on OS X. Both Clang and GCC give similar errors for the assembly code in svolume_mmx.c. Since bugzilla probably isn't followed actively by many people, and since I'm pretty clueless about this assembly stuff, I decided to raise the issue here on the mailing list, where there may be more people with more clue. Here are the errors from Clang: CC libpulsecore_2.98_la-svolume_mmx.lo pulsecore/svolume_mmx.c:108:43: error: register %rcx is only available in 64-bit mode " je 2f \n\t" ^ <inline asm>:5:9: note: instantiated into assembly here movd (%rcx, %edi, 4), %mm0 ^~~~ pulsecore/svolume_mmx.c:124:43: error: register %rcx is only available in 64-bit mode "3: \n\t" /* do samples in groups of 2 */ ^ <inline asm>:33:9: note: instantiated into assembly here movq (%rcx, %edi, 4), %mm0 ^~~~ pulsecore/svolume_mmx.c:137:43: error: register %rcx is only available in 64-bit mode "5: \n\t" /* do samples in groups of 4 */ ^ <inline asm>:59:9: note: instantiated into assembly here movq (%rcx, %edi, 4), %mm0 ^~~~ pulsecore/svolume_mmx.c:138:43: error: register %rcx is only available in 64-bit mode " movq (%q1, %3, 4), %%mm0 \n\t" /* | v1h | v1l | v0h | v0l | */ ^ <inline asm>:60:10: note: instantiated into assembly here movq 8(%rcx, %edi, 4), %mm2 ^~~~ pulsecore/svolume_mmx.c:181:43: error: register %rcx is only available in 64-bit mode " je 2f \n\t" ^ <inline asm>:9:9: note: instantiated into assembly here movd (%rcx, %edi, 4), %mm0 ^~~~ pulsecore/svolume_mmx.c:199:43: error: register %rcx is only available in 64-bit mode "3: \n\t" /* do samples in groups of 2 */ ^ <inline asm>:39:9: note: instantiated into assembly here movq (%rcx, %edi, 4), %mm0 ^~~~ pulsecore/svolume_mmx.c:214:43: error: register %rcx is only available in 64-bit mode "5: \n\t" /* do samples in groups of 4 */ ^ <inline asm>:73:9: note: instantiated into assembly here movq (%rcx, %edi, 4), %mm0 ^~~~ pulsecore/svolume_mmx.c:215:43: error: register %rcx is only available in 64-bit mode " movq (%q1, %3, 4), %%mm0 \n\t" /* | v1h | v1l | v0h | v0l | */ ^ <inline asm>:74:10: note: instantiated into assembly here movq 8(%rcx, %edi, 4), %mm2 ^~~~ 8 errors generated. make[3]: *** [libpulsecore_2.98_la-svolume_mmx.lo] Error 1 make[2]: *** [install] Error 2 make[1]: *** [install-recursive] Error 1 make: *** [install] Error 2 [1] https://bugs.freedesktop.org/show_bug.cgi?id=55733 -- Tanu