Xi Ruoyao <xry...@xry111.site> 于2024年3月20日周三 15:12写道：
>
> We were assuming TYPE_NO_NAMED_ARGS_STDARG_P don't have any named
> arguments and there is nothing to advance, but that is not the case
> for (...) functions returning by hidden reference which have one such
> artificial argument. This is causing gcc.dg/c23-stdarg-{6,8,9}.c to
> fail.
>
> Fix the issue by checking if arg.type is NULL, as r14-9503 explains.
>
> gcc/ChangeLog:
>
> PR target/114175
> * config/mips/mips.cc (mips_setup_incoming_varargs): Only skip
> mips_function_arg_advance for TYPE_NO_NAMED_ARGS_STDARG_P
> functions if arg.type is NULL.
> ---
>
> Bootstrapped and regtested on mips64el-linux-gnuabi64. Ok for trunk?
>
Thanks. LGTM.
> gcc/config/mips/mips.cc | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/gcc/config/mips/mips.cc b/gcc/config/mips/mips.cc
> index 68e2ae8d8fa..ce764a5cb35 100644
> --- a/gcc/config/mips/mips.cc
> +++ b/gcc/config/mips/mips.cc
> @@ -6834,7 +6834,13 @@ mips_setup_incoming_varargs (cumulative_args_t cum,
> argument. Advance a local copy of CUM past the last "real" named
> argument, to find out how many registers are left over. */
> local_cum = *get_cumulative_args (cum);
> - if (!TYPE_NO_NAMED_ARGS_STDARG_P (TREE_TYPE (current_function_decl)))
> +
> + /* For a C23 variadic function w/o any named argument, and w/o an
> + artifical argument for large return value, skip advancing args.
> + There is such an artifical argument iff. arg.type is non-NULL
> + (PR 114175). */
> + if (!TYPE_NO_NAMED_ARGS_STDARG_P (TREE_TYPE (current_function_decl))
> + || arg.type != NULL_TREE)
> mips_function_arg_advance (pack_cumulative_args (&local_cum), arg);
>
> /* Found out how many registers we need to save. */
> --
> 2.44.0
>
