MLton runs fine on the Sparc architecture.
When compiling for Sparc, MLton targets the 32-bit Sparc architecture (i.e., Sparc V8).
When compiling for Sparc, MLton doesn’t support native code generation (-codegen native). Hence, performance is not as good as it might be and compile times are longer. Also, the quality of code generated by gcc is important. By default, MLton calls gcc -O1. You can change this by calling MLton with -cc-opt -O2. We have seen this speed up some programs by as much as 30%, especially those involving floating point; however, it can also more than double compile times.
When compiling for Sparc, MLton uses -align 8 by default. While this speeds up reals, it also may increase object sizes. If your program does not make significant use of reals, you might see a speedup with -align 4.