https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114136
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-13 branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:96e6576a1ba0080e70fef4a6f9cc3129fcf6f008 commit r13-8397-g96e6576a1ba0080e70fef4a6f9cc3129fcf6f008 Author: Jakub Jelinek <ja...@redhat.com> Date: Fri Mar 1 15:42:52 2024 +0100 calls: Further fixes for TYPE_NO_NAMED_ARGS_STDARG_P handling [PR114136] On Tue, Feb 27, 2024 at 04:41:32PM +0000, Richard Earnshaw wrote: > On Arm the PR107453 change is causing all anonymous arguments to be passed on the > stack, which is incorrect per the ABI. On a target that uses > 'pretend_outgoing_vararg_named', why is it correct to set n_named_args to > zero? Is it enough to guard both the statements you've added with > !targetm.calls.pretend_outgoing_args_named? The TYPE_NO_NAMED_ARGS_STDARG_P functions (C23 fns like void foo (...) {}) have NULL type_arg_types, so the list_length (type_arg_types) isn't done for it, but it should be handled as if it was non-NULL but list length was 0. So, for the if (type_arg_types != 0) n_named_args = (list_length (type_arg_types) /* Count the struct value address, if it is passed as a parm. */ + structure_value_addr_parm); else if (TYPE_NO_NAMED_ARGS_STDARG_P (funtype)) n_named_args = 0; else /* If we know nothing, treat all args as named. */ n_named_args = num_actuals; case, I think guarding it by any target hooks is wrong, although I guess it should have been n_named_args = structure_value_addr_parm; instead of n_named_args = 0; For the second if (type_arg_types != 0 && targetm.calls.strict_argument_naming (args_so_far)) ; else if (type_arg_types != 0 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far)) /* Don't include the last named arg. */ --n_named_args; else if (TYPE_NO_NAMED_ARGS_STDARG_P (funtype)) n_named_args = 0; else /* Treat all args as named. */ n_named_args = num_actuals; I think we should treat those as if type_arg_types was non-NULL with 0 elements in the list, except the --n_named_args would for !structure_value_addr_parm lead to n_named_args = -1, I think we want 0 for that case. 2024-03-01 Jakub Jelinek <ja...@redhat.com> PR middle-end/114136 * calls.cc (expand_call): For TYPE_NO_NAMED_ARGS_STDARG_P set n_named_args initially before INIT_CUMULATIVE_ARGS to structure_value_addr_parm rather than 0, after it don't modify it if strict_argument_naming and clear only if !pretend_outgoing_varargs_named. (cherry picked from commit b5377928a2a5cd2a79eda59e2eba7d0511bf7566)
