how to complie the the test 'mm' or 'mt-matmul'?

[Tianhang-Cheng]

I would like to complie the test 'mm' or 'mat-mul' with rv32im (I build a sodor that can support rv32im), but I don't know how to modify the makefile. I can only compile them in riscv64-unknown-elf. If I use riscv32-unknown-elf in makefile, there will be 'undefined reference to `__sync_fetch_and_add_4' error.

really thanks!

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/opt/riscv32/lib/gcc/riscv32-unknown-elf/9.2.0/../../../../riscv32-unknown-elf/bin/ld: /tmp/ccysEb0N.o: in function .L0 ': mm_main.c:(.text+0x22): **undefined reference to __sync_fetch_and_add_4'**
collect2: error: ld returned 1 exit status
make: *** [Makefile:55：mm.riscv] error 1