Using todays build of tcc I confirmed this problem on ARM mac (bdec3c534583066cf097543f265ad620a8baa30d, tcc version 0.9.27 mob:bdec3c5 2023-02-03T18:04:56+01:00 (AArch64 Darwin))

Compile the below using `-c a.c` on either clang or gcc. I tried with Apple clang version 14.0.0 (clang-1400.0.29.202) and gcc version 12.2.0 (Homebrew GCC 12.2.0)

a.c
int get() { return 1; }

Then compile the below using `tcc -g b.c a.o`. You get an "unrecognized file type" error. Following these instructions on linux will create a working binary

a.o: error: a.o: unrecognized file type

b.c
int get();
int main() {
return get();
}