Re: [RFA] Fix too many "no debugging symbols found" warnings.

[Doug Evans <dje@google.com>]

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On Thu, Jul 2, 2009 at 3:44 PM, Pedro Alves<pedro@codesourcery.com> wrote:
>> > OTOH, if GDB is printing nothing, then printing a sole:
>> >
>> >  "(no debugging symbols found)"
>> >
>> > out of the blue, doesn't ever seem useful to me.  Is that ever really useful?
>>
>> Well, s@no debugging symbols found@no debugging symbols found in
>> /usr/lib/libfoo.so@.
>
> What's the output in the non-auto-loaded case, then?
>
>  "Reading symbols from /lib/librt.so.1... (no debugging symbols found in /lib/librt.so.1) ...done."
>
> ?

Reading symbols from /lib/librt.so.1... (no debugging symbols found) ...done.

The patch knows it has already printed the path in that case.

>> Users would like to know that something isn't going to work because
>> debug info is missing.
>> That is useful.
>
> It is useful to know when a module doesn't have debug info, sure, but,
> that transient warning has been printed like that for years, as is,
> without showing the shared library name.  In that state, I'm not sure
> how useful it has been.  It appears to me we have some freedom to play
> with it, and when it is printed.

True.

>> We could tell them differently of course.  Maybe an option to "info
>> shared" to only show the ones without debug info or some such.
>
> We do have a "Syms Read" column in info shared's output, maybe we
> should extend that from "Yes, No" -> "Yes, Sorry-I've-tried-but-didn't-find-any, No".
> Then the user could ask GDB if it has debug info any time, instead of having
> to look up the log.

"works for me"

>> > Wouldn't tweaking the "no debugging symbols found" predicate make everyone happy?
>>
>> "Tweaking" as in only printing "no debugging symbols found [in
>> /usr/lib/libfoo.so]" if (from_tty || info_verbose), and never printing
>> it for auto-loaded libraries?
>
> s/auto-loaded libraries/auto-loaded libraries, modules, executables, whatnot/,
> yes.

I'm not sure if I'd be happy nor not, but see attached patch.

> I'll back away from arguing now, and let you decide to do what you think
> is best.  I don't think I'll be miserable with the change.  (though with a feeling
> of wrongly named option in my stomach.)

The attached patch adds an optional regex argument to "info shared"
and marks in the output libraries without debugging info.
With this addition, I don't see a real need for a "set print
symbol-loading-warning/whatever" option, thus I deleted it.

Ok to check in?

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2009-07-10  Doug Evans  <dje@google.com>

	* NEWS: Remove note on `set print symbol-loading'.
	Add note about new regex arg to "info sharedlibrary".
	* main.c (captured_main): Pass !batch for from_tty when calling
	symbol_file_add_main.
	* objfiles.h (objfile_has_partial_symbols): Declare.
	(objfile_has_full_symbols): Declare.
	* objfiles.c (objfile_has_partial_symbols): New function.
	(have_partial_symbols): Use it.
	(objfile_has_full_symbols): New function.
	(have_full_symbols): Use it.
	* solib.c (solib_read_symbols): Back out patch of 2008-07-10.
	Add test for info_verbose for symbol loading messages for
	consistency with symfile.c.
	(info_sharedlibrary_command): Handle optional parameter of regex of
	libraries to list.  Inform user of libraries without debugging info.
	* symfile.c (print_symbol_loading): Delete.
	(symbol_file_add_with_addrs_or_offsets): Back out patch of 2008-07-10.
	Print "no debugging symbols found" only if from_tty || info_verbose;
	and only check file being loaded, not all files.
	(reread_symbols): Test file being loaded for whether it has symbols,
	not all files.
	(__initialize_symfile): Delete `set print symbol-loading'.
	* symfile.h (print_symbol_loading): Delete.

	* doc/gdb.texinfo: Delete `set print symbol-loading'.
	Add note on new optional regex arg to `info sharedlibrary'.

Index: NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.316
diff -u -p -r1.316 NEWS
--- NEWS	2 Jul 2009 21:57:27 -0000	1.316
+++ NEWS	10 Jul 2009 21:50:19 -0000
@@ -33,6 +33,9 @@ remote targets.  To use this feature, sp
 with the `remote:' prefix, either via the `set sysroot' command or via
 the `--with-sysroot' configure-time option.
 
+* "info sharedlibrary" now takes an optional regex of libraries to show,
+and it now reports if a shared library has no debugging information.
+
 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
 now complete on file names.
 
@@ -225,10 +228,6 @@ set sh calling-convention
 show sh calling-convention
   Control the calling convention used when calling SH target functions.
 
-set print symbol-loading
-show print symbol-loading
-  Control printing of symbol loading messages.
-
 set debug timestamp
 show debug timestamp
   Control display of timestamps with GDB debugging output.
Index: main.c
===================================================================
RCS file: /cvs/src/src/gdb/main.c,v
retrieving revision 1.76
diff -u -p -r1.76 main.c
--- main.c	27 Apr 2009 10:24:08 -0000	1.76
+++ main.c	10 Jul 2009 21:50:19 -0000
@@ -801,14 +801,14 @@ Excess command line arguments ignored. (
          open it, better only print one error message.
          catch_command_errors returns non-zero on success! */
       if (catch_command_errors (exec_file_attach, execarg, !batch, RETURN_MASK_ALL))
-	catch_command_errors (symbol_file_add_main, symarg, 0, RETURN_MASK_ALL);
+	catch_command_errors (symbol_file_add_main, symarg, !batch, RETURN_MASK_ALL);
     }
   else
     {
       if (execarg != NULL)
 	catch_command_errors (exec_file_attach, execarg, !batch, RETURN_MASK_ALL);
       if (symarg != NULL)
-	catch_command_errors (symbol_file_add_main, symarg, 0, RETURN_MASK_ALL);
+	catch_command_errors (symbol_file_add_main, symarg, !batch, RETURN_MASK_ALL);
     }
 
   if (corearg && pidarg)
Index: objfiles.c
===================================================================
RCS file: /cvs/src/src/gdb/objfiles.c,v
retrieving revision 1.84
diff -u -p -r1.84 objfiles.c
--- objfiles.c	23 Jun 2009 16:28:45 -0000	1.84
+++ objfiles.c	10 Jul 2009 21:50:19 -0000
@@ -677,6 +677,22 @@ objfile_relocate (struct objfile *objfil
   breakpoint_re_set ();
 }
 \f
+/* Return non-zero if OBJFILE has partial symbols.  */
+
+int
+objfile_has_partial_symbols (struct objfile *objfile)
+{
+  return objfile->psymtabs != NULL;
+}
+
+/* Return non-zero if OBJFILE has full symbols.  */
+
+int
+objfile_has_full_symbols (struct objfile *objfile)
+{
+  return objfile->symtabs != NULL;
+}
+
 /* Many places in gdb want to test just to see if we have any partial
    symbols available.  This function returns zero if none are currently
    available, nonzero otherwise. */
@@ -688,10 +704,8 @@ have_partial_symbols (void)
 
   ALL_OBJFILES (ofp)
   {
-    if (ofp->psymtabs != NULL)
-      {
-	return 1;
-      }
+    if (objfile_has_partial_symbols (ofp))
+      return 1;
   }
   return 0;
 }
@@ -707,10 +721,8 @@ have_full_symbols (void)
 
   ALL_OBJFILES (ofp)
   {
-    if (ofp->symtabs != NULL)
-      {
-	return 1;
-      }
+    if (objfile_has_full_symbols (ofp))
+      return 1;
   }
   return 0;
 }
Index: objfiles.h
===================================================================
RCS file: /cvs/src/src/gdb/objfiles.h,v
retrieving revision 1.59
diff -u -p -r1.59 objfiles.h
--- objfiles.h	15 Jan 2009 16:35:22 -0000	1.59
+++ objfiles.h	10 Jul 2009 21:50:19 -0000
@@ -478,6 +478,10 @@ extern void free_all_objfiles (void);
 
 extern void objfile_relocate (struct objfile *, struct section_offsets *);
 
+extern int objfile_has_partial_symbols (struct objfile *objfile);
+
+extern int objfile_has_full_symbols (struct objfile *objfile);
+
 extern int have_partial_symbols (void);
 
 extern int have_full_symbols (void);
Index: solib.c
===================================================================
RCS file: /cvs/src/src/gdb/solib.c,v
retrieving revision 1.121
diff -u -p -r1.121 solib.c
--- solib.c	9 Jul 2009 13:39:17 -0000	1.121
+++ solib.c	10 Jul 2009 21:50:19 -0000
@@ -489,12 +489,12 @@ solib_read_symbols (struct so_list *so, 
 
   if (so->symbols_loaded)
     {
-      if (from_tty)
+      if (from_tty || info_verbose)
 	printf_unfiltered (_("Symbols already loaded for %s\n"), so->so_name);
     }
   else if (so->abfd == NULL)
     {
-      if (from_tty)
+      if (from_tty | info_verbose)
 	printf_unfiltered (_("Symbol file not found for %s\n"), so->so_name);
     }
   else
@@ -510,7 +510,7 @@ solib_read_symbols (struct so_list *so, 
                              "Error while reading shared library symbols:\n");
           return 0;
         }
-      if (from_tty && print_symbol_loading)
+      if (from_tty || info_verbose)
         printf_unfiltered (_("Loaded symbols for %s\n"), so->so_name);
       so->symbols_loaded = 1;
       return 1;
@@ -801,16 +801,26 @@ solib_add (char *pattern, int from_tty, 
    DESCRIPTION
 
    Walk through the shared library list and print information
-   about each attached library.
+   about each attached library matching PATTERN.  If PATTERN is elided,
+   print them all.
  */
 
 static void
-info_sharedlibrary_command (char *ignore, int from_tty)
+info_sharedlibrary_command (char *pattern, int from_tty)
 {
   struct so_list *so = NULL;	/* link map state variable */
   int header_done = 0;
+  int so_missing_debug_info = 0;
   int addr_width;
 
+  if (pattern)
+    {
+      char *re_err = re_comp (pattern);
+
+      if (re_err)
+	error (_("Invalid regexp: %s"), re_err);
+    }
+
   /* "0x", a little whitespace, and two hex digits per byte of pointers.  */
   addr_width = 4 + (gdbarch_ptr_bit (target_gdbarch) / 4);
 
@@ -820,6 +830,9 @@ info_sharedlibrary_command (char *ignore
     {
       if (so->so_name[0])
 	{
+	  if (pattern && ! re_exec (so->so_name))
+	    continue;
+
 	  if (!header_done)
 	    {
 	      printf_unfiltered ("%-*s%-*s%-12s%s\n", addr_width, "From",
@@ -840,14 +853,26 @@ info_sharedlibrary_command (char *ignore
 			           (LONGEST) so->addr_high,
 	                           addr_width - 4)
 			       : "");
-	  printf_unfiltered ("%-12s", so->symbols_loaded ? "Yes" : "No");
+
+	  if (so->symbols_loaded
+	      && !objfile_has_partial_symbols (so->objfile)
+	      && !objfile_has_full_symbols (so->objfile))
+	    {
+	      so_missing_debug_info = 1;
+	      printf_unfiltered ("%-12s", "Yes (*)");
+	    }
+	  else
+	    printf_unfiltered ("%-12s", !so->symbols_loaded ? "No" : "Yes");
+
 	  printf_unfiltered ("%s\n", so->so_name);
 	}
     }
   if (so_list_head == NULL)
-    {
-      printf_unfiltered (_("No shared libraries loaded at this time.\n"));
-    }
+    printf_unfiltered (_("No shared libraries loaded at this time.\n"));
+  else if (! header_done && pattern)
+    printf_unfiltered (_("No shared libraries matched.\n"));
+  else if (header_done && so_missing_debug_info)
+    printf_unfiltered (_("(*): Shared library is missing debugging information.\n"));
 }
 
 /* Return 1 if ADDRESS lies within SOLIB.  */
Index: symfile.c
===================================================================
RCS file: /cvs/src/src/gdb/symfile.c,v
retrieving revision 1.237
diff -u -p -r1.237 symfile.c
--- symfile.c	2 Jul 2009 17:25:58 -0000	1.237
+++ symfile.c	10 Jul 2009 21:50:19 -0000
@@ -171,13 +171,6 @@ Dynamic symbol table reloading multiple 
 		    value);
 }
 
-/* If non-zero, gdb will notify the user when it is loading symbols
-   from a file.  This is almost always what users will want to have happen;
-   but for programs with lots of dynamically linked libraries, the output
-   can be more noise than signal.  */
-
-int print_symbol_loading = 1;
-
 /* If non-zero, shared library symbols will be added automatically
    when the inferior is created, new libraries are loaded, or when
    attaching to the inferior.  This is almost always what users will
@@ -989,12 +982,9 @@ symbol_file_add_with_addrs_or_offsets (b
 	deprecated_pre_add_symbol_hook (name);
       else
 	{
-          if (print_symbol_loading)
-	    {
-	      printf_unfiltered (_("Reading symbols from %s..."), name);
-	      wrap_here ("");
-	      gdb_flush (gdb_stdout);
-	    }
+	  printf_unfiltered (_("Reading symbols from %s..."), name);
+	  wrap_here ("");
+	  gdb_flush (gdb_stdout);
 	}
     }
   syms_from_objfile (objfile, addrs, offsets, num_offsets,
@@ -1007,7 +997,7 @@ symbol_file_add_with_addrs_or_offsets (b
 
   if ((flags & OBJF_READNOW) || readnow_symbol_files)
     {
-      if ((from_tty || info_verbose) && print_symbol_loading)
+      if (from_tty || info_verbose)
 	{
 	  printf_unfiltered (_("expanding to full symbols..."));
 	  wrap_here ("");
@@ -1049,15 +1039,12 @@ symbol_file_add_with_addrs_or_offsets (b
       xfree (debugfile);
     }
 
-  if (!have_partial_symbols () && !have_full_symbols ()
-      && print_symbol_loading)
+  if ((from_tty || info_verbose)
+      && !objfile_has_partial_symbols (objfile)
+      && !objfile_has_full_symbols (objfile))
     {
       wrap_here ("");
-      printf_unfiltered (_("(no debugging symbols found)"));
-      if (from_tty || info_verbose)
-        printf_unfiltered ("...");
-      else
-        printf_unfiltered ("\n");
+      printf_unfiltered (_("(no debugging symbols found)..."));
       wrap_here ("");
     }
 
@@ -1066,10 +1053,7 @@ symbol_file_add_with_addrs_or_offsets (b
       if (deprecated_post_add_symbol_hook)
 	deprecated_post_add_symbol_hook ();
       else
-	{
-	  if (print_symbol_loading)
-	    printf_unfiltered (_("done.\n"));
-	}
+	printf_unfiltered (_("done.\n"));
     }
 
   /* We print some messages regardless of whether 'from_tty ||
@@ -2422,7 +2406,8 @@ reread_symbols (void)
 	         zero is OK since dbxread.c also does what it needs to do if
 	         objfile->global_psymbols.size is 0.  */
 	      (*objfile->sf->sym_read) (objfile, 0);
-	      if (!have_partial_symbols () && !have_full_symbols ())
+	      if (!objfile_has_partial_symbols (objfile)
+		  && !objfile_has_full_symbols (objfile))
 		{
 		  wrap_here ("");
 		  printf_unfiltered (_("(no debugging symbols found)\n"));
@@ -4189,12 +4174,4 @@ the global debug-file directory prepende
 				     NULL,
 				     show_debug_file_directory,
 				     &setlist, &showlist);
-
-  add_setshow_boolean_cmd ("symbol-loading", no_class,
-                           &print_symbol_loading, _("\
-Set printing of symbol loading messages."), _("\
-Show printing of symbol loading messages."), NULL,
-                           NULL,
-                           NULL,
-                           &setprintlist, &showprintlist);
 }
Index: symfile.h
===================================================================
RCS file: /cvs/src/src/gdb/symfile.h,v
retrieving revision 1.51
diff -u -p -r1.51 symfile.h
--- symfile.h	16 Jun 2009 18:49:25 -0000	1.51
+++ symfile.h	10 Jul 2009 21:50:19 -0000
@@ -284,13 +284,6 @@ extern char *obconcat (struct obstack *o
 
 			/*   Variables   */
 
-/* If non-zero, gdb will notify the user when it is loading symbols
-   from a file.  This is almost always what users will want to have happen;
-   but for programs with lots of dynamically linked libraries, the output
-   can be more noise than signal.  */
-
-extern int print_symbol_loading;
-
 /* If non-zero, shared library symbols will be added automatically
    when the inferior is created, new libraries are loaded, or when
    attaching to the inferior.  This is almost always what users will
Index: doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.605
diff -u -p -r1.605 gdb.texinfo
--- doc/gdb.texinfo	10 Jul 2009 10:35:17 -0000	1.605
+++ doc/gdb.texinfo	10 Jul 2009 22:00:27 -0000
@@ -12565,22 +12565,6 @@ is printed as follows:
 @item show opaque-type-resolution
 Show whether opaque types are resolved or not.
 
-@kindex set print symbol-loading
-@cindex print messages when symbols are loaded
-@item set print symbol-loading
-@itemx set print symbol-loading on
-@itemx set print symbol-loading off
-The @code{set print symbol-loading} command allows you to enable or
-disable printing of messages when @value{GDBN} loads symbols.
-By default, these messages will be printed, and normally this is what
-you want.  Disabling these messages is useful when debugging applications
-with lots of shared libraries where the quantity of output can be more
-annoying than useful.
-
-@kindex show print symbol-loading
-@item show print symbol-loading
-Show whether messages will be printed when @value{GDBN} loads symbols.
-
 @kindex maint print symbols
 @cindex symbol dump
 @kindex maint print psymbols
@@ -13453,9 +13437,11 @@ command:
 @table @code
 @kindex info sharedlibrary
 @kindex info share
-@item info share
-@itemx info sharedlibrary
-Print the names of the shared libraries which are currently loaded.
+@item info share @var{regex}
+@itemx info sharedlibrary @var{regex}
+Print the names of the shared libraries which are currently loaded
+that match @var{regex}.  If @var{regex} is omitted then print
+all shared libraries that are loaded.
 
 @kindex sharedlibrary
 @kindex share