C++ translation improvement

[Zack Weinberg <zack at codesourcery dot com>]

I'd forgotten I had this patch sitting around in my tree.  It improves
translation of certain C++ diagnostic messages, by restructuring them
so complete sentences appear in gcc.pot.  (See the gettext manual for
why this is desirable.)

The last time I posted it, someone pointed out that the indentation
logic is broken for non-unibyte character sets, but I don't see any
way to do it correctly with the existing API. It can be fixed in a
follow-up patch if someone figures out how.

Will apply if bootstrap finishes successfully.

zw

        * call.c: Include intl.h.
        (print_z_candidate): Always use inform; get rid of errfn
        argument. Reorganize so that all the strings get picked up
        by xgettext.  Note obligation of caller to pass first argument
        through gettext.
        (print_z_candidates): Update to match.  Indent second and
        successive candidates by strlen() of translated message.
        (joust): Restructure ambiguous-conversion pedwarn so that
        translators see a complete sentence.  Update calls to
        print_z_candidate.

        * Make-lang.in (cp/call.o): Update dependencies.

===================================================================
Index: cp/Make-lang.in
--- cp/Make-lang.in	3 Apr 2003 23:26:03 -0000	1.147
+++ cp/Make-lang.in	7 Apr 2003 01:42:11 -0000
@@ -244,7 +244,7 @@ cp/typeck.o: cp/typeck.c $(CXX_TREE_H) $
    diagnostic.h
 cp/class.o: cp/class.c $(CXX_TREE_H) $(TM_H) flags.h toplev.h $(RTL_H) $(TARGET_H)
 cp/call.o: cp/call.c $(CXX_TREE_H) $(TM_H) flags.h toplev.h $(RTL_H) $(EXPR_H) \
-     diagnostic.h gt-cp-call.h
+     diagnostic.h intl.h gt-cp-call.h
 cp/friend.o: cp/friend.c $(CXX_TREE_H) $(TM_H) flags.h $(RTL_H) toplev.h $(EXPR_H)
 cp/init.o: cp/init.c $(CXX_TREE_H) $(TM_H) flags.h $(RTL_H) $(EXPR_H) toplev.h \
   except.h
===================================================================
Index: cp/call.c
--- cp/call.c	29 Mar 2003 00:49:34 -0000	1.374
+++ cp/call.c	7 Apr 2003 01:42:12 -0000
@@ -36,6 +36,7 @@ Boston, MA 02111-1307, USA.  */
 #include "toplev.h"
 #include "expr.h"
 #include "diagnostic.h"
+#include "intl.h"
 
 extern int inhibit_warnings;
 
@@ -56,8 +57,7 @@ static void op_error (enum tree_code, en
 static tree build_object_call (tree, tree);
 static tree resolve_args (tree);
 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
-static void print_z_candidate (const char *msgid, struct z_candidate *,
-			       void (*)(const char *, ...));
+static void print_z_candidate (const char *, struct z_candidate *);
 static void print_z_candidates (struct z_candidate *);
 static tree build_this (tree);
 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
@@ -2437,34 +2437,39 @@ equal_functions (tree fn1, tree fn2)
   return fn1 == fn2;
 }
 
-/* Print information about one overload candidate CANDIDATE.  STR is the
-   text to print before the candidate itself and ERRFN is the routine
-   (i.e. error, warning or pedwarn) used to do the printing.  */
+/* Print information about one overload candidate CANDIDATE.  MSGSTR
+   is the text to print before the candidate itself.
+
+   NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
+   to have been run through gettext by the caller.  This wart makes
+   life simpler in print_z_candidates and for the translators.  */
 
 static void
-print_z_candidate (const char *msgid, struct z_candidate *candidate,
-		   void (*errfn)(const char *, ...))
+print_z_candidate (const char *msgstr, struct z_candidate *candidate)
 {
   if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
     {
       if (TREE_VEC_LENGTH (candidate->convs) == 3)
-	errfn ("%s %D(%T, %T, %T) <built-in>", msgid, candidate->fn,
-	       TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
-	       TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)),
-	       TREE_TYPE (TREE_VEC_ELT (candidate->convs, 2)));
+	inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
+		TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
+		TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)),
+		TREE_TYPE (TREE_VEC_ELT (candidate->convs, 2)));
       else if (TREE_VEC_LENGTH (candidate->convs) == 2)
-	errfn ("%s %D(%T, %T) <built-in>", msgid, candidate->fn,
-	       TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
-	       TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)));
+	inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
+		TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
+		TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)));
       else
-	errfn ("%s %D(%T) <built-in>", msgid, candidate->fn,
-	       TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)));
+	inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
+		TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)));
     }
   else if (TYPE_P (candidate->fn))
-    errfn ("%s %T <conversion>", msgid, candidate->fn);
+    inform ("%s %T <conversion>", msgstr, candidate->fn);
+  else if (candidate->viable == -1)
+    inform ("%H%s %+#D <near match>",
+	    &DECL_SOURCE_LOCATION (candidate->fn), msgstr, candidate->fn);
   else
-    errfn ("%H%s %+#D%s", &DECL_SOURCE_LOCATION (candidate->fn), msgid,
-	   candidate->fn, candidate->viable == -1 ? " <near match>" : "");
+    inform ("%H%s %+#D",
+	    &DECL_SOURCE_LOCATION (candidate->fn), msgstr, candidate->fn);
 }
 
 static void
@@ -2496,11 +2501,24 @@ print_z_candidates (struct z_candidate *
 	}
     }
 
-  str = "candidates are:";
-  for (; candidates; candidates = candidates->next)
-    {
-      print_z_candidate (str, candidates, error);
-      str = "               "; 
+  str = _("candidates are:");
+  print_z_candidate (str, candidates);
+  if (candidates->next)
+    {
+      /* Indent successive candidates by the length of the translation of
+	 the above string.  */
+      size_t len = strlen (str) + 1;
+      char *spaces = alloca (len);
+      memset (spaces, ' ', len-1);
+      spaces[len] = '\0';
+
+      candidates = candidates->next;
+      do
+	{
+	  print_z_candidate (spaces, candidates);
+	  candidates = candidates->next;
+	}
+      while (candidates);
     }
 }
 
@@ -5866,12 +5884,12 @@ tweak:
         {
 	  if (warn)
 	    {
-	      print_z_candidate ("ISO C++ says that ", w, pedwarn);
-	      /* Translators note: This message is a continuation of the
-	         previous one, aligned on the right.  */
-	      print_z_candidate ("              and ", l, pedwarn);
-	      pedwarn ("are ambiguous even though the worst conversion \
-for the former is better than the worst conversion for the latter");
+	      pedwarn ("\
+ISO C++ says that these are ambiguous, even \
+though the worst conversion for the first is better than \
+the worst conversion for the second:");
+	      print_z_candidate (_("candidate 1:"), w);
+	      print_z_candidate (_("candidate 2:"), l);
 	    }
 	  else
 	    add_warning (w, l);