Mainline compiler: Digraphs (part 2 of 2)

[Neil Booth <NeilB at earthling dot net>]

This updates the mainline compiler to honour digraphs depending upon
the -std= setting.  Along with the cpplib patch, it fixes Gnats #352.

Would someone with the relevant authority give this a quick look?  OK
to commit?

Bootstrapping on i386 Linux.

Thanks,

Neil.

	* c-common.h (flag_digraphs): New.
	* c-decl.c (c_decode_option): Set flag_digraphs as appropriate.
	* c-lex.c (yylex): Use flag_digraphs to decide whether to
	honour digraphs.

Index: c-common.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/c-common.h,v
retrieving revision 1.22
diff -u -p -r1.22 c-common.h
--- c-common.h	2000/07/03 03:55:22	1.22
+++ c-common.h	2000/07/09 11:01:03
@@ -181,6 +181,10 @@ extern int flag_traditional;
 
 extern int flag_isoc99;
 
+/* Nonzero means accept digraphs.  */
+
+extern int flag_digraphs;
+
 /* Nonzero means warn about suggesting putting in ()'s.  */
 
 extern int warn_parentheses;
Index: c-decl.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/c-decl.c,v
retrieving revision 1.126
diff -u -p -r1.126 c-decl.c
--- c-decl.c	2000/07/02 05:22:58	1.126
+++ c-decl.c	2000/07/09 11:01:12
@@ -330,6 +330,10 @@ int flag_traditional;
 
 int flag_isoc99 = 0;
 
+/* Nonzero means accept digraphs.  */
+
+int flag_digraphs = 1;
+
 /* Nonzero means that we have builtin functions, and main is an int */
 
 int flag_hosted = 1;
@@ -491,6 +495,7 @@ c_decode_option (argc, argv)
     {
       flag_traditional = 1;
       flag_writable_strings = 1;
+      flag_digraphs = 0;
     }
   else if (!strcmp (p, "-fallow-single-precision"))
     flag_allow_single_precision = 1;
@@ -511,6 +516,7 @@ c_decode_option (argc, argv)
     {
       flag_traditional = 0;
       flag_writable_strings = 0;
+      flag_digraphs = 1;
     }
   else if (!strncmp (p, "-std=", 5))
     {
@@ -535,6 +541,7 @@ c_decode_option (argc, argv)
 	  flag_no_asm = 1;
 	  flag_no_nonansi_builtin = 1;
 	  flag_isoc99 = 0;
+	  flag_digraphs = 0;
 	}
       else if (!strcmp (argstart, "iso9899:199409"))
 	{
@@ -551,6 +558,7 @@ c_decode_option (argc, argv)
 	  flag_no_asm = 1;
 	  flag_no_nonansi_builtin = 1;
 	  flag_isoc99 = 1;
+	  flag_digraphs = 1;
 	}
       else if (!strcmp (argstart, "gnu89"))
 	{
@@ -559,6 +567,7 @@ c_decode_option (argc, argv)
 	  flag_no_asm = 0;
 	  flag_no_nonansi_builtin = 0;
 	  flag_isoc99 = 0;
+	  flag_digraphs = 0;
 	}
       else if (!strcmp (argstart, "gnu9x") || !strcmp (argstart, "gnu99"))
 	{
@@ -567,6 +576,7 @@ c_decode_option (argc, argv)
 	  flag_no_asm = 0;
 	  flag_no_nonansi_builtin = 0;
 	  flag_isoc99 = 1;
+	  flag_digraphs = 1;
 	}
       else
 	error ("unknown C standard `%s'", argstart);
Index: c-lex.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/c-lex.c,v
retrieving revision 1.86
diff -u -p -r1.86 c-lex.c
--- c-lex.c	2000/06/30 18:20:37	1.86
+++ c-lex.c	2000/07/09 11:01:14
@@ -2383,17 +2383,20 @@ yylex ()
 
 	      /* digraphs */
 	    case ':':
-	      if (c1 == '>')
+	      if (c1 == '>' && flag_digraphs)
 		{ value = ']'; goto done; }
 	      break;
 	    case '<':
-	      if (c1 == '%')
-		{ value = '{'; indent_level++; goto done; }
-	      if (c1 == ':')
-		{ value = '['; goto done; }
+	      if (flag_digraphs)
+		{
+		  if (c1 == '%')
+		    { value = '{'; indent_level++; goto done; }
+		  if (c1 == ':')
+		    { value = '['; goto done; }
+		}
 	      break;
 	    case '%':
-	      if (c1 == '>')
+	      if (c1 == '>' && flag_digraphs)
 		{ value = '}'; indent_level--; goto done; }
 	      break;
 	    }