On Wed, Jun 4, 2014 at 3:04 PM, Torsten Bögershausen <tboegi@xxxxxx> wrote: > > On 2014-06-04 05.38, David Turner wrote: > [] >> [] >> diff --git a/Makefile b/Makefile >> index a53f3a8..dd2127a 100644 >> --- a/Makefile >> +++ b/Makefile >> @@ -1326,6 +1326,11 @@ else >> COMPAT_OBJS += compat/win32mmap.o >> endif >> endif >> +ifdef NO_SSE42 >> + BASIC_CFLAGS += -DNO_SSE42 >> +else >> + BASIC_CFLAGS += -msse4.2 >> +endif > This does work for some people, but break for others, like the systems in my test-lab. > On 2 different systems the gcc has support for -msse4.2, but the processor has not, > and t5511 fails with "Illegal instruction". > How can that be? > The maintainer of a Linux distro wants to ship gcc with all possible features, > an the end-user can compile the code with all the features his very processor has. I think glibc code uses cpuid instruction to decide whether to use optimized version. May be we can do the same? If we go that route and have a way to detect sse support from compiler, then we can drop NO_SSE42, enable all and pick one at runtime. -- Duy -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html