https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108423
--- Comment #7 from Martin Uecker <muecker at gwdg dot de> --- * gimplify_type_size does not recurse into pointer, record, or function types (the later are not mentioned). * the C FE has code to emit fake TYPE_DECLs for pointer types in c-decl.cc/grokdeclarator * In the FE, size expressions in parameters go into pending_sizes and emitted at a start of a function c-decl.cc/store_parm_decls * function.cc/gimplify_parm_type only considers types with non-constant size and otherwise recurses only into pointer types How all this fits together is a bit of mystery to me. Modifying gimplify_parm_type to also recurse into function types seems to fix this bug (and PR107557) but I am not sure if this is the right fix. Then there should also be similar missing cases related to records/unions?
