re PR fortran/32223 (Backslash handling inconsistent)

2007-06-07  Steven G. Kargl  <kargl@gcc.gnu.org>
	    Jerry DeLisle  <jvdelisle@gcc.gnu.org>

	PR fortran/32223
	* match.c (gfc_match_special_char): New function.  Match special char.
	Add handling '\0'.
	* match.h: Add prototype.
	* io.c (next_char): Use it.
	* primary.c (next_string_char): Ditto.

Co-Authored-By: Jerry DeLisle <jvdelisle@gcc.gnu.org>

From-SVN: r125557

gcc/fortran/ChangeLog

+2007-06-07  Steven G. Kargl  <kargl@gcc.gnu.org>
+	    Jerry DeLisle  <jvdelisle@gcc.gnu.org>
+
+	PR fortran/32223
+	* match.c (gfc_match_special_char): New function.  Match special char.
+	Add handling '\0'.
+	* match.h: Add prototype.
+	* io.c (next_char): Use it.
+	* primary.c (next_string_char): Ditto.
+
 2007-06-06  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	* decl.c: Miscellaneous whitespace fixes.

gcc/fortran/io.c

@@ -141,40 +141,17 @@ next_char (int in_string)
 
   if (gfc_option.flag_backslash && c == '\\')
     {
+      int tmp;
       locus old_locus = gfc_current_locus;
 
-      switch (gfc_next_char_literal (1))
-	{
-	case 'a':
-	  c = '\a';
-	  break;
-	case 'b':
-	  c = '\b';
-	  break;
-	case 't':
-	  c = '\t';
-	  break;
-	case 'f':
-	  c = '\f';
-	  break;
-	case 'n':
-	  c = '\n';
-	  break;
-	case 'r':
-	  c = '\r';
-	  break;
-	case 'v':
-	  c = '\v';
-	  break;
-	case '\\':
-	  c = '\\';
-	  break;
+      /* Use a temp variable to avoid side effects from gfc_match_special_char
+	 since it uses an int * for its argument.  */
+      tmp = (int)c;
 
-	default:
-	  /* Unknown backslash codes are simply not expanded.  */
+      if (gfc_match_special_char (&tmp) == MATCH_NO)
 	gfc_current_locus = old_locus;
-	  break;
-	}
+
+      c = (char)tmp;
 
       if (!(gfc_option.allow_std & GFC_STD_GNU) && !inhibit_warnings)
 	gfc_warning ("Extension: backslash character at %C");

gcc/fortran/match.c

@@ -64,6 +64,56 @@ mstring intrinsic_operators[] = {
 
 /******************** Generic matching subroutines ************************/
 
+/* See if the next character is a special character that has
+   escaped by a \ via the -fbackslash option.  */
+
+match
+gfc_match_special_char (int *c)
+{
+
+  match m;
+
+  m = MATCH_YES;
+
+  switch (gfc_next_char_literal (1))
+    {
+    case 'a':
+      *c = '\a';
+      break;
+    case 'b':
+      *c = '\b';
+      break;
+    case 't':
+      *c = '\t';
+      break;
+    case 'f':
+      *c = '\f';
+      break;
+    case 'n':
+      *c = '\n';
+      break;
+    case 'r':
+      *c = '\r';
+      break;
+    case 'v':
+      *c = '\v';
+      break;
+    case '\\':
+      *c = '\\';
+      break;
+    case '0':
+      *c = '\0';
+      break;
+    default:
+      /* Unknown backslash codes are simply not expanded.  */
+      m = MATCH_NO;
+      break;
+    }
+
+  return m;
+}
+
+
 /* In free form, match at least one space.  Always matches in fixed
    form.  */
 

gcc/fortran/match.h

@@ -39,6 +39,7 @@ extern gfc_st_label *gfc_statement_label;
 /* match.c.  */
 
 /* Generic match subroutines.  */
+match gfc_match_special_char (int *);
 match gfc_match_space (void);
 match gfc_match_eos (void);
 match gfc_match_small_literal_int (int *, int *);

gcc/fortran/primary.c

@@ -732,38 +732,8 @@ next_string_char (char delimiter)
     {
       old_locus = gfc_current_locus;
 
-      switch (gfc_next_char_literal (1))
-	{
-	case 'a':
-	  c = '\a';
-	  break;
-	case 'b':
-	  c = '\b';
-	  break;
-	case 't':
-	  c = '\t';
-	  break;
-	case 'f':
-	  c = '\f';
-	  break;
-	case 'n':
-	  c = '\n';
-	  break;
-	case 'r':
-	  c = '\r';
-	  break;
-	case 'v':
-	  c = '\v';
-	  break;
-	case '\\':
-	  c = '\\';
-	  break;
-
-	default:
-	  /* Unknown backslash codes are simply not expanded */
+      if (gfc_match_special_char (&c) == MATCH_NO)
 	gfc_current_locus = old_locus;
-	  break;
-	}
 
       if (!(gfc_option.allow_std & GFC_STD_GNU) && !inhibit_warnings)
 	gfc_warning ("Extension: backslash character at %C");