> LGTM. I do wonder if this could be documented somewhere if not > already. Because I suspect there are other places which miss that if > TYPE_PRECISION are equal, you might still need a cast for boolean > types. Maybe a helper function might be useful too.
The knowledge is indeed encoded in useless_type_conversion_p, int_fits_type_p, fits_to_tree_p (which ought to be called fits_to_type_p AFAICS) but I'm not sure how to factor it out in a predicate. But we can certainly add a blurb in tree.def for BOOLEAN_TYPE, for example: diff --git a/gcc/tree.def b/gcc/tree.def index c4ad8d08f10..19533cfe77c 100644 --- a/gcc/tree.def +++ b/gcc/tree.def @@ -135,7 +135,9 @@ DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0) DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0) /* Boolean type (true or false are the only values). Looks like an - INTEGRAL_TYPE. */ + INTEGER_TYPE, but must be dealt with specially because TYPE_PRECISION + may be arbitrary despite the restricted set of valid values (in other + words, boolean types with TYPE_PRECISION > 1 exist in some languages). DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0) /* Integer types in all languages, including char in C. -- Eric Botcazou
