c-decl.c (store_parm_decls_oldstyle): Let diagnostic machinery decide if the warning will be printed.

* c-decl.c (store_parm_decls_oldstyle): Let diagnostic machinery
decide if the warning will be printed.
* calls.c (expand_call): Likewise.
* function.c (init-function_start): Likewise.

* common.opt (-fdiagnostics-show-option): New.
* opts.c (option_enabled): Accept the option index instead of a
pointer to the option descriptor.
* opts.h (option_enabled): Likewise.
* toplev.c (print_switch_values): Pass option index, not option
descriptor.
* diagnostic.h (diagnostic_info): Add option_index.
* diagnostic.c: Include opts.h.
(diagnostic_set_info): Initialize option_index.
(diagnostic_report_diagnostic): Amend option name if appropriate.
(warning): Check to see if the specified warning is enabled.
Store option index.
* doc/invoke.texi (-fdiagnostics-show-options): Document.

From-SVN: r99169

gcc/ChangeLog

@@ -1,3 +1,24 @@
+2005-05-03  DJ Delorie  <dj@redhat.com>
+
+	* c-decl.c (store_parm_decls_oldstyle): Let diagnostic machinery
+	decide if the warning will be printed.
+	* calls.c (expand_call): Likewise.
+	* function.c (init-function_start): Likewise.
+
+	* common.opt (-fdiagnostics-show-option): New.
+	* opts.c (option_enabled): Accept the option index instead of a
+	pointer to the option descriptor.
+	* opts.h (option_enabled): Likewise.
+	* toplev.c (print_switch_values): Pass option index, not option
+	descriptor.
+	* diagnostic.h (diagnostic_info): Add option_index.
+	* diagnostic.c: Include opts.h.
+	(diagnostic_set_info): Initialize option_index.
+	(diagnostic_report_diagnostic): Amend option name if appropriate.
+	(warning): Check to see if the specified warning is enabled.
+	Store option index.
+	* doc/invoke.texi (-fdiagnostics-show-options): Document.
+
 2005-05-03  Richard Henderson  <rth@redhat.com>
 
 	* config/rs6000/rs6000.h (REG_CLASS_CONTENTS): Fix ALL_REGS and

gcc/c-decl.c

@@ -6011,8 +6011,8 @@ store_parm_decls_oldstyle (tree fndecl, const struct c_arg_info *arg_info)
     gcc_assert (TREE_CODE (b->decl) != PARM_DECL || !DECL_WEAK (b->decl));
 #endif
 
-  if (warn_old_style_definition && !in_system_header)
-    warning (0, "%Jold-style function definition", fndecl);
+  if (!in_system_header)
+    warning (OPT_Wold_style_definition, "%Jold-style function definition", fndecl);
 
   /* Match each formal parameter name with its declaration.  Save each
      decl in the appropriate TREE_PURPOSE slot of the parmids chain.  */

gcc/calls.c

@@ -1934,8 +1934,8 @@ expand_call (tree exp, rtx target, int ignore)
 
   /* Warn if this value is an aggregate type,
      regardless of which calling convention we are using for it.  */
-  if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
-    warning (0, "function call has aggregate value");
+  if (AGGREGATE_TYPE_P (TREE_TYPE (exp)))
+    warning (OPT_Waggregate_return, "function call has aggregate value");
 
   /* If the result of a pure or const function call is ignored (or void),
      and none of its arguments are volatile, we can avoid expanding the

gcc/common.opt

@@ -336,6 +336,10 @@ fdiagnostics-show-location=
 Common Joined RejectNegative
 -fdiagnostics-show-location=[once|every-line]	How often to emit source location at the beginning of line-wrapped diagnostics
 
+fdiagnostics-show-option
+Common Var(diagnostics_show_options)
+Amend appropriate diagnostic messages with the command line option that controls them.
+
 fdump-
 Common Joined RejectNegative
 -fdump-<type>	Dump various compiler internals to a file

gcc/diagnostic.c

@@ -40,6 +40,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #include "diagnostic.h"
 #include "langhooks.h"
 #include "langhooks-def.h"
+#include "opts.h"
 
 
 /* Prototypes.  */
@@ -120,6 +121,7 @@ diagnostic_set_info (diagnostic_info *diagnostic, const char *msgid,
   diagnostic->message.format_spec = _(msgid);
   diagnostic->location = location;
   diagnostic->kind = kind;
+  diagnostic->option_index = 0;
 }
 
 /* Return a malloc'd string describing a location.  The caller is
@@ -333,6 +335,11 @@ diagnostic_report_diagnostic (diagnostic_context *context,
 
   if (diagnostic_count_diagnostic (context, diagnostic))
     {
+      if (diagnostics_show_options && diagnostic->option_index)
+	diagnostic->message.format_spec
+	  = ACONCAT ((diagnostic->message.format_spec,
+		      " [", cl_options[diagnostic->option_index].opt_text, "]", NULL));
+
       pp_prepare_to_format (context->printer, &diagnostic->message,
 			    &diagnostic->location);
       (*diagnostic_starter (context)) (context, diagnostic);
@@ -412,13 +419,18 @@ inform (const char *msgid, ...)
 /* A warning.  Use this for code which is correct according to the
    relevant language specification but is likely to be buggy anyway.  */
 void
-warning (int opt ATTRIBUTE_UNUSED, const char *msgid, ...)
+warning (int opt, const char *msgid, ...)
 {
   diagnostic_info diagnostic;
   va_list ap;
 
+  if (opt && ! option_enabled (opt))
+    return;
+
   va_start (ap, msgid);
   diagnostic_set_info (&diagnostic, msgid, &ap, input_location, DK_WARNING);
+  diagnostic.option_index = opt;
+
   report_diagnostic (&diagnostic);
   va_end (ap);
 }

gcc/diagnostic.h

@@ -43,6 +43,8 @@ typedef struct
   location_t location;
   /* The kind of diagnostic it is about.  */
   diagnostic_t kind;
+  /* Which OPT_* directly controls this diagnostic.  */
+  int option_index;
 } diagnostic_info;
 
 #define pedantic_error_kind() (flag_pedantic_errors ? DK_ERROR : DK_WARNING)

gcc/doc/invoke.texi

@@ -206,7 +206,8 @@ Objective-C and Objective-C++ Dialects}.
 @item Language Independent Options
 @xref{Language Independent Options,,Options to Control Diagnostic Messages Formatting}.
 @gccoptlist{-fmessage-length=@var{n}  @gol
--fdiagnostics-show-location=@r{[}once@r{|}every-line@r{]}}
+-fdiagnostics-show-location=@r{[}once@r{|}every-line@r{]}} @gol
+-fdiagnostics-show-options
 
 @item Warning Options
 @xref{Warning Options,,Options to Request or Suppress Warnings}.
@@ -2090,6 +2091,13 @@ messages reporter to emit the same source location information (as
 prefix) for physical lines that result from the process of breaking
 a message which is too long to fit on a single line.
 
+@item -fdiagnostics-show-options
+@opindex fdiagnostics-show-options
+This option instructs the diagnostic machinery to add text to each
+diagnostic emitted, which indicates which command line option directly
+controls that diagnostic, when such an option is known to the
+diagnostic machinery.
+
 @end table
 
 @node Warning Options

gcc/function.c

@@ -3850,9 +3850,8 @@ init_function_start (tree subr)
 
   /* Warn if this value is an aggregate type,
      regardless of which calling convention we are using for it.  */
-  if (warn_aggregate_return
-      && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
-    warning (0, "function returns an aggregate");
+  if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
+    warning (OPT_Waggregate_return, "function returns an aggregate");
 }
 
 /* Make sure all values used by the optimization passes have sane

gcc/opts.c

@@ -1400,8 +1400,9 @@ wrap_help (const char *help, const char *item, unsigned int item_width)
    a simple on-off switch.  */
 
 int
-option_enabled (const struct cl_option *option)
+option_enabled (int opt_idx)
 {
+  const struct cl_option *option = &(cl_options[opt_idx]);
   if (option->flag_var)
     switch (option->var_cond)
       {

gcc/opts.h

@@ -71,7 +71,7 @@ extern const char **in_fnames;
 extern unsigned num_in_fnames;
 
 extern void decode_options (unsigned int argc, const char **argv);
-extern int option_enabled (const struct cl_option *);
+extern int option_enabled (int opt_idx);
 extern void print_filtered_help (unsigned int);
 
 #endif

gcc/toplev.c

@@ -1360,7 +1360,7 @@ print_switch_values (FILE *file, int pos, int max,
 
   for (j = 0; j < cl_options_count; j++)
     if ((cl_options[j].flags & CL_REPORT)
-	&& option_enabled (&cl_options[j]) > 0)
+	&& option_enabled (j) > 0)
       pos = print_single_switch (file, pos, max, indent, sep, term,
 				 "", cl_options[j].opt_text);