Building with zig and failing at runtime on mir_hash_1

[giann]

I'm trying to build MIR with my build.zig for buzz so that users are not required to build it separately by hand and also for it to be automatically built for the current platform.

-> https://github.com/buzz-language/buzz/blob/mir/build.zig#L639-L703

It builds and links ok but crashes at runtime here:

    frame #0: 0x0000000101216270 libbuzz.dylib`mir_hash_1 [inlined] mir_get_key_part(v=<unavailable>, len=<unavailable>, relax_p=<unavailable>) at mir-hash.h:0 [opt]
   62     return state ^ mir_mum (state, p2, relax_p);
   63   }
   64  
-> 65   static inline uint64_t mir_hash_1 (const void *key, size_t len, uint64_t seed, int relax_p) {
   66     const uint8_t *v = (const uint8_t *) key;
   67     uint64_t r = seed + len;
   68 

@vnmakarov Do you have any idea as to what I might be missing?

Note that it works perfectly when building by hand with make

[giann]

We found that the issue is that MIR seems to rely on undefined behaviour somewhere.
Building with zig ensures that any undefined behaviour results in a trace trap.
Building with -fno-sanitize=undefined which removes this behaviour, fixed it.

[giann]

Nevermind you had -fno-sanitize=undefined in GNUMakefile I just didn't see it