Allow modulus in constant expressions #132
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Not sure if this was intentional, but I noticed `eval2(...)` will compile-time evaluate a modulus but `is_const_expr(...)` won't. This causes chibicc to try and compile some arrays as VLAs, which was causing problems for me. This change adds `ND_MOD` to the list of allowed constant expressions. It's possible I'm missing something, but https://en.cppreference.com/w/c/language/constant_expression seems to imply that all numeric operators (including modulus) should be OK in constant expressions. And `ND_DIV` is already allowed in the function so it seems `ND_MOD` should be as well.
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Not sure if this was intentional, but I noticed
eval2(...)will compile-time evaluate a modulus butis_const_expr(...)won't. This causes chibicc to try and compile some arrays as VLAs, which was causing problems for me. This change addsND_MODto the list of allowed constant expressions.It's possible I'm missing something, but https://en.cppreference.com/w/c/language/constant_expression seems to imply that all numeric operators (including modulus) should be OK in constant expressions. And
ND_DIVis already allowed in the function so it seemsND_MODshould be as well.