I use $ ~/gcc/bin/gcc --version gcc (GCC) 4.3.0 20070307 (experimental)
to compile double rdtsc_cputick; double rdtsc () { unsigned long eax, edx; asm volatile ("rdtsc" : "=a" (eax), "=d" (edx)); return rdtsc_cputick * ((unsigned long long) edx << 32 | eax); } and I receive the error $ ~/gcc/bin/gcc -c rdtsc.c -march=prescott rdtsc.c: In function rdtsc: rdtsc.c:9: internal compiler error: in gen_split_1956, at config/i386/sse.md:128 -- Summary: ICE with double and unsigned long long with - march=prescott Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: schnetter at aei dot mpg dot de GCC build triplet: i386-apple-darwin8.8.1 GCC host triplet: i386-apple-darwin8.8.1 GCC target triplet: i386-apple-darwin8.8.1 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31076