driver: Improve option diagnostics [PR103465]

It happens that options are parsed and various diagnostics happen
in finish_options. That's a proper place as the function is also called
for optimize/target attributes (pragmas). However, it is possible that
target overwrites an option from command line and so the diagnostics
does not happen. That's fixed in the patch.

- options are parsed and finish_options is called:

  if (opts->x_flag_unwind_tables
      && !targetm_common.unwind_tables_default
      && opts->x_flag_reorder_blocks_and_partition
      && (ui_except == UI_SJLJ || ui_except >= UI_TARGET))
    {
      if (opts_set->x_flag_reorder_blocks_and_partition)
        inform (loc,
		"%<-freorder-blocks-and-partition%> does not support "
		"unwind info on this architecture");
      opts->x_flag_reorder_blocks_and_partition = 0;
      opts->x_flag_reorder_blocks = 1;
    }

It's not triggered because of opts->x_flag_unwind_tables is false by default, but
the option is overwritten in target:

...
  if (TARGET_64BIT_P (opts->x_ix86_isa_flags))
    {
      if (opts->x_optimize >= 1)
	SET_OPTION_IF_UNSET (opts, opts_set, flag_omit_frame_pointer,
			     !USE_IX86_FRAME_POINTER);
      if (opts->x_flag_asynchronous_unwind_tables
	  && TARGET_64BIT_MS_ABI)
	SET_OPTION_IF_UNSET (opts, opts_set, flag_unwind_tables, 1);
...

	PR driver/103465

gcc/ChangeLog:

	* opts.c (finish_options): More part of diagnostics to ...
	(diagnose_options): ... here. Call the function from both
	finish_options and process_options.
	* opts.h (diagnose_options): Declare.
	* toplev.c (process_options): Call diagnose_options.

1 files changed, 2 insertions, 0 deletions

diff --git a/gcc/opts.h b/gcc/opts.h
index 4c2b77e..8003d26 100644
--- a/gcc/opts.h
+++ b/gcc/opts.h
@@ -428,6 +428,8 @@ extern bool target_handle_option (struct gcc_options *opts,
 extern void finish_options (struct gcc_options *opts,
 			    struct gcc_options *opts_set,
 			    location_t loc);
+extern void diagnose_options (gcc_options *opts, gcc_options *opts_set,
+			      location_t loc);
 extern void print_help (struct gcc_options *opts, unsigned int lang_mask, const
 			char *help_option_argument);
 extern void default_options_optimization (struct gcc_options *opts,