https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108348
--- Comment #4 from Kewen Lin <linkw at gcc dot gnu.org> --- (In reply to Kewen Lin from comment #3) > There seem to be two alternatives to fix this, one is to raise error in > rs6000_pass_by_reference like what we do in rs6000_function_arg, but we need > something like mma_return_type_error to avoid re-erroring; the other is to > teach the function rs6000_opaque_type_invalid_use_p about function call > statement on arguments and return values. For now, the argument and return > value checking is against the modes directly rather than the types, maybe to > unique them into rs6000_opaque_type_invalid_use_p is better? > > Hi @Segher and @Peter, what do you think of this? Ah, the later is a bad idea, as the current checking is for non MMA but the function argument and return values checking should happen all the time. With further thinking, the fix can be: (always return false for MMA modes, let rs6000_function_arg to raise error msg.) diff --git a/gcc/config/rs6000/rs6000-call.cc b/gcc/config/rs6000/rs6000-call.cc index 59c51fa3579..6767a1f541c 100644 --- a/gcc/config/rs6000/rs6000-call.cc +++ b/gcc/config/rs6000/rs6000-call.cc @@ -2013,6 +2013,11 @@ rs6000_pass_by_reference (cumulative_args_t, const function_arg_info &arg) { if (TARGET_DEBUG_ARG) fprintf (stderr, "function_arg_pass_by_reference: AltiVec\n"); + /* We do not allow MMA types being used as function arguments, + return false to avoid the ICE on the copying for passing by + reference. */ + if (TYPE_MODE (arg.type) == OOmode || TYPE_MODE (arg.type) == XOmode) + return 0; return 1; }