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

1 files changed, 12 insertions, 0 deletions

diff --git a/gcc/opts.c b/gcc/opts.c
index 45b12fe..f96ed16 100644
--- a/gcc/opts.c
+++ b/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);