opts-common.c (decode_cmdline_option): Print empty string argument as "" in decoded->orig_option_with_args_text.

* opts-common.c (decode_cmdline_option): Print empty string
	argument as "" in decoded->orig_option_with_args_text.
	* gcc.c (execute): Print empty string argument as ""
	in the verbose output.
	(do_spec_1): Keep empty string argument.

	testsuite/
	* gcc.dg/cpp/include7.c: New test.

From-SVN: r170426

gcc/ChangeLog

@@ -1,3 +1,11 @@
+2011-02-23  Jie Zhang  <jie@codesourcery.com>
+
+	* opts-common.c (decode_cmdline_option): Print empty string
+	argument as "" in decoded->orig_option_with_args_text.
+	* gcc.c (execute): Print empty string argument as ""
+	in the verbose output.
+	(do_spec_1): Keep empty string argument.
+
 2011-02-23  Nathan Froyd  <froydnj@codesourcery.com>
 
 	* config.gcc: Declare score-* and crx-* obsolete.

gcc/gcc.c

@@ -2538,13 +2538,20 @@ execute (void)
 			}
 		      fputc ('"', stderr);
 		    }
+		  /* If it's empty, print "".  */
+		  else if (!**j)
+		    fprintf (stderr, " \"\"");
 		  else
 		    fprintf (stderr, " %s", *j);
 		}
 	    }
 	  else
 	    for (j = commands[i].argv; *j; j++)
-	      fprintf (stderr, " %s", *j);
+	      /* If it's empty, print "".  */
+	      if (!**j)
+		fprintf (stderr, " \"\"");
+	      else
+		fprintf (stderr, " %s", *j);
 
 	  /* Print a pipe symbol after all but the last command.  */
 	  if (i + 1 != n_commands)
@@ -4423,6 +4430,10 @@ do_spec_1 (const char *spec, int inswitch, const char *soft_matched_part)
   int i;
   int value;
 
+  /* If it's an empty string argument to a switch, keep it as is.  */
+  if (inswitch && !*p)
+    arg_going = 1;
+
   while ((c = *p++))
     /* If substituting a switch, treat all chars like letters.
        Otherwise, NL, SPC, TAB and % are special.  */
@@ -5149,7 +5160,8 @@ do_spec_1 (const char *spec, int inswitch, const char *soft_matched_part)
 	  case '*':
 	    if (soft_matched_part)
 	      {
-		do_spec_1 (soft_matched_part, 1, NULL);
+		if (soft_matched_part[0])
+		  do_spec_1 (soft_matched_part, 1, NULL);
 		do_spec_1 (" ", 0, NULL);
 	      }
 	    else

gcc/opts-common.c

@@ -607,11 +607,15 @@ decode_cmdline_option (const char **argv, unsigned int lang_mask,
     {
       if (i < result)
 	{
+	  size_t len;
 	  if (opt_index == OPT_SPECIAL_unknown)
 	    decoded->canonical_option[i] = argv[i];
 	  else
 	    decoded->canonical_option[i] = NULL;
-	  total_len += strlen (argv[i]) + 1;
+	  len = strlen (argv[i]);
+	  /* If the argument is an empty string, we will print it as "" in
+	     orig_option_with_args_text.  */
+	  total_len += (len != 0 ? len : 2) + 1;
 	}
       else
 	decoded->canonical_option[i] = NULL;
@@ -637,7 +641,14 @@ decode_cmdline_option (const char **argv, unsigned int lang_mask,
     {
       size_t len = strlen (argv[i]);
 
-      memcpy (p, argv[i], len);
+      /* Print the empty string verbally.  */
+      if (len == 0)
+	{
+	  *p++ = '"';
+	  *p++ = '"';
+	}
+      else
+	memcpy (p, argv[i], len);
       p += len;
       if (i == result - 1)
 	*p++ = 0;

gcc/testsuite/ChangeLog

@@ -1,3 +1,7 @@
+2011-02-23  Jie Zhang  <jie@codesourcery.com>
+
+	* gcc.dg/cpp/include7.c: New test.
+
 2011-02-22  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/47242

gcc/testsuite/gcc.dg/cpp/include7.c

@@ -0,0 +1,3 @@
+/* { dg-do compile } */
+/* { dg-options "-I \"\"" } */
+