common.opt: Add -gdwarf.

	* common.opt: Add -gdwarf.
	* opts.c (common_handle_option): Handle it.
	* gcc.c (ASM_DEBUG_SPEC): Don't expect "-2" for DWARF.

Co-Authored-By: Jason Merrill <jason@redhat.com>

From-SVN: r197675

gcc/ChangeLog

+2013-04-10  Senthil Kumar Selvaraj  <senthil_kumar.selvaraj@atmel.com>
+            Jason Merrill  <jason@redhat.com>
+
+	* common.opt: Add -gdwarf.
+	* opts.c (common_handle_option): Handle it.
+	* gcc.c (ASM_DEBUG_SPEC): Don't expect "-2" for DWARF.
+
 2013-04-10  Richard Biener  <rguenther@suse.de>
 
 	* passes.c (execute_todo): Do not call ggc_collect conditional here.

gcc/common.opt

@@ -2308,9 +2308,13 @@ Common JoinedOrMissing
 Generate debug information in default format
 
 gcoff
-Common JoinedOrMissing Negative(gdwarf-)
+Common JoinedOrMissing Negative(gdwarf)
 Generate debug information in COFF format
 
+gdwarf
+Common JoinedOrMissing Negative(gdwarf-)
+Generate debug information in default version of DWARF format
+
 gdwarf-
 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
 Generate debug information in DWARF v2 (or later) format

gcc/gcc.c

@@ -627,7 +627,7 @@ proper position among the other output files.  */
      && defined(HAVE_AS_GDWARF2_DEBUG_FLAG) && defined(HAVE_AS_GSTABS_DEBUG_FLAG)
 #  define ASM_DEBUG_SPEC						\
       (PREFERRED_DEBUGGING_TYPE == DBX_DEBUG				\
-       ? "%{!g0:%{gdwarf-2*:--gdwarf2}%{!gdwarf-2*:%{g*:--gstabs}}}" ASM_MAP	\
+       ? "%{!g0:%{gdwarf*:--gdwarf2}%{!gdwarf*:%{g*:--gstabs}}}" ASM_MAP	\
        : "%{!g0:%{gstabs*:--gstabs}%{!gstabs*:%{g*:--gdwarf2}}}" ASM_MAP)
 # else
 #  if defined(DBX_DEBUGGING_INFO) && defined(HAVE_AS_GSTABS_DEBUG_FLAG)

gcc/opts.c

@@ -1699,6 +1699,18 @@ common_handle_option (struct gcc_options *opts,
       set_debug_level (SDB_DEBUG, false, arg, opts, opts_set, loc);
       break;
 
+    case OPT_gdwarf:
+      if (arg && strlen(arg) != 0)
+        {
+          error_at (loc, "%<-gdwarf%s%> is ambiguous; "
+                    "use %<-gdwarf-%s%> for DWARF version "
+                    "or %<-gdwarf -g%s%> for debug level", arg, arg, arg);
+          break;
+        }
+      else
+        {
+          value = opts->x_dwarf_version;
+        }
     case OPT_gdwarf_:
       if (value < 2 || value > 4)
 	error_at (loc, "dwarf version %d is not supported", value);