Sorry to interrupt some great work here, just to say that I, too, experience problems with "mario kart 64 (usa)" aka mariokrtu

Quote
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x00000001cd9c0c08

VM Regions Near 0x1cd9c0c08:
CG backing stores 00000001c8fbf000-00000001c8fed000 [ 184K] rw-/rw- SM=SHM
-->
MALLOC_TINY 00007ff5fac00000-00007ff5fad00000 [ 1024K] rw-/rwx SM=COW

Application Specific Information:
objc[36520]: garbage collection is OFF

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 mess64 0x000000010850a511 N64TexturePipeT::MaskCoupled(int*, int*, int*, int*, int, rdp_poly_state const&) + 133
1 mess64 0x000000010850d614 N64TexturePipeT::Cycle(Color*, Color*, int, int, unsigned int, unsigned int, rdp_span_aux*, rdp_poly_state const&) + 878
2 mess64 0x0000000108512613 n64_rdp::SpanDraw1Cycle(int, poly_manager<unsigned int, rdp_poly_state, 8, 32000>::extent_t const&, rdp_poly_state const&, int) + 2447
3 mess64 0x0000000108507699 delegate_base<void, int, poly_manager<unsigned int, rdp_poly_state, 8, 32000>::extent_t const&, rdp_poly_state const&, int, _noparam>::operator()(int, poly_manager<unsigned int, rdp_poly_state, 8, 32000>::extent_t const&, rdp_poly_state const&, int) const + 81
4 mess64 0x0000000108507875 poly_manager<unsigned int, rdp_poly_state, 8,

I'ts a clean build, with symbols, 64bit, on mac (lion).
I know my build is evil since it's build with OPTIMIZE=3, but I've tested a non-optimized build beside this one with no more luck.

If needed, just give me pointers on what you want me to test/report.