c++: fix old cast warnings

We still have a few old C casts in lalr1.cc, let's get rid of them.
Reported by Frank Heckenbach.

Actually, let's monitor all our casts using easy to grep macros.
Let's use these macros to use the C++ standard casts when we are in
C++.

* data/skeletons/c.m4 (b4_cast_define): New.
* data/skeletons/glr.c, data/skeletons/glr.cc,
* data/skeletons/lalr1.cc, data/skeletons/stack.hh,
* data/skeletons/yacc.c:
Use it and/or its casts.

* tests/actions.at, tests/cxx-type.at,
* tests/glr-regression.at, tests/headers.at, tests/torture.at,
* tests/types.at:
Use YY_CAST instead of C casts.

* configure.ac (warn_cxx): Add -Wold-style-cast.
* doc/bison.texi: Disable it.

tests/actions.at

@@ -772,10 +772,10 @@ static
   static int counter = 0;
 
   int c = ]AT_VAL[]m4_ifval([$6], [.ival])[ = counter++;
+  assert (c <= YY_CAST (int, strlen (source)));
   /* As in BASIC, line numbers go from 10 to 10.  */
   ]AT_LOC_FIRST_LINE[ = ]AT_LOC_FIRST_COLUMN[ = (10 * c);
   ]AT_LOC_LAST_LINE[ = ]AT_LOC_LAST_COLUMN[ = ]AT_LOC_FIRST_LINE[ + 9;
-  assert (c <= (int) strlen (source));
   if (source[c])
     fprintf (stderr, "sending: '%c'", source[c]);
   else
@@ -1780,7 +1780,8 @@ float: UNTYPED INT
                                  yy::parser::token::INT,
                                   EOF}]],
                                [[{UNTYPED, INT, EOF}]]),
-                 [AT_VAL.ival = (int) toknum * 10; AT_VAL.fval = (float) toknum / 10.0f;])[
+                 [AT_VAL.ival = YY_CAST (int, toknum) * 10;
+                  AT_VAL.fval = YY_CAST (float, toknum) / 10.0f;])[
 ]AT_MAIN_DEFINE[
 ]])
 
@@ -1805,7 +1806,6 @@ AT_CLEANUP
 ])
 
 m4_map_args([AT_TEST], [yacc.c], [glr.c], [lalr1.cc], [glr.cc])
-
 m4_popdef([AT_TEST])
 
 ## -------------------------------------------------- ##
@@ -1897,7 +1897,7 @@ exp:
 
 %%
 ]AT_YYERROR_DEFINE[
-]AT_YYLEX_DEFINE(["bcd"], [*lvalp = (int) ((toknum + 1) * 10)])[
+]AT_YYLEX_DEFINE(["bcd"], [*lvalp = YY_CAST (int, (toknum + 1) * 10)])[
 ]AT_MAIN_DEFINE[
 ]])
 AT_BISON_OPTION_POPDEFS

tests/cxx-type.at

@@ -178,7 +178,7 @@ main (int argc, char **argv)
 
                 do
                   {
-                    buffer[i++] = (char) c;
+                    buffer[i++] = YY_CAST (char, c);
                     colNum += 1;
                     assert (i != sizeof buffer - 1);
                     c = getchar ();
@@ -187,8 +187,8 @@ main (int argc, char **argv)
 
                 ungetc (c, stdin);
                 buffer[i++] = 0;
-                tok = isupper ((unsigned char) buffer[0]) ? TYPENAME : ID;
-                yylval = new_term (strcpy ((char *) malloc (i), buffer));
+                tok = isupper (YY_CAST (unsigned char, buffer[0])) ? TYPENAME : ID;
+                yylval = new_term (strcpy (YY_CAST (char *, malloc (i)), buffer));
               }
             else
               {
@@ -206,7 +206,7 @@ main (int argc, char **argv)
 static Node *
 new_nterm (char const *form, Node *child0, Node *child1, Node *child2)
 {
-  Node *node = (Node *) malloc (sizeof (Node));
+  Node *node = YY_CAST (Node *, malloc (sizeof (Node)));
   node->nterm.isNterm = 1;
   node->nterm.parents = 0;
   node->nterm.form = form;
@@ -225,7 +225,7 @@ new_nterm (char const *form, Node *child0, Node *child1, Node *child2)
 static Node *
 new_term (char *text)
 {
-  Node *node = (Node *) malloc (sizeof (Node));
+  Node *node = YY_CAST (Node *, malloc (sizeof (Node)));
   node->term.isNterm = 0;
   node->term.parents = 0;
   node->term.text = text;
@@ -255,30 +255,27 @@ free_node (Node *node)
 static char *
 node_to_string (Node *node)
 {
-  char *child0;
-  char *child1;
-  char *child2;
-  char *buffer;
+  char *res;
   if (!node)
     {
-      buffer = (char *) malloc (1);
-      buffer[0] = 0;
+      res = YY_CAST (char *, malloc (1));
+      res[0] = 0;
     }
   else if (node->nodeInfo.isNterm == 1)
     {
-      child0 = node_to_string (node->nterm.children[0]);
-      child1 = node_to_string (node->nterm.children[1]);
-      child2 = node_to_string (node->nterm.children[2]);
-      buffer = (char *) malloc (strlen (node->nterm.form) + strlen (child0)
-                                + strlen (child1) + strlen (child2) + 1);
-      sprintf (buffer, node->nterm.form, child0, child1, child2);
-      free (child0);
-      free (child1);
+      char *child0 = node_to_string (node->nterm.children[0]);
+      char *child1 = node_to_string (node->nterm.children[1]);
+      char *child2 = node_to_string (node->nterm.children[2]);
+      res = YY_CAST (char *, malloc (strlen (node->nterm.form) + strlen (child0)
+                                     + strlen (child1) + strlen (child2) + 1));
+      sprintf (res, node->nterm.form, child0, child1, child2);
       free (child2);
+      free (child1);
+      free (child0);
     }
   else
-    buffer = strdup (node->term.text);
-  return buffer;
+    res = strdup (node->term.text);
+  return res;
 }
 
 ]]

tests/glr-regression.at

@@ -153,7 +153,7 @@ var_list:
     { $$ = $1; }
   | var ',' var_list
     {
-      char *s = (char *) realloc ($1, strlen ($1) + 1 + strlen ($3) + 1);
+      char *s = YY_CAST (char *, realloc ($1, strlen ($1) + 1 + strlen ($3) + 1));
       strcat (s, ",");
       strcat (s, $3);
       free ($3);
@@ -172,7 +172,6 @@ int
 yylex (void)
 {
   char buf[50];
-  char *s;
   assert (!feof (stdin));
   switch (fscanf (input, " %1[a-z,]", buf))
   {
@@ -181,15 +180,19 @@ yylex (void)
   case EOF:
     return 0;
   default:
+    if (fscanf (input, "%49s", buf) != 1)
+      return 0;
+    else
+      {
+        char *s;
+        assert (strlen (buf) < sizeof buf - 1);
+        s = YY_CAST (char *, malloc (strlen (buf) + 1));
+        strcpy (s, buf);
+        yylval = s;
+        return 'V';
+      }
     break;
   }
-  if (fscanf (input, "%49s", buf) != 1)
-    return 0;
-  assert (strlen (buf) < sizeof buf - 1);
-  s = (char *) malloc (strlen (buf) + 1);
-  strcpy (s, buf);
-  yylval = s;
-  return 'V';
 }
 
 int
@@ -419,7 +422,7 @@ make_value (char const *parent, char const *child)
 {
   char const format[] = "%s <- %s";
   char *value = *ptrs_next++ =
-    (char *) malloc (strlen (parent) + strlen (child) + sizeof format);
+    YY_CAST (char *, malloc (strlen (parent) + strlen (child) + sizeof format));
   sprintf (value, format, parent, child);
   return value;
 }
@@ -429,7 +432,7 @@ merge (YYSTYPE s1, YYSTYPE s2)
 {
   char const format[] = "merge{ %s and %s }";
   char *value = *ptrs_next++ =
-    (char *) malloc (strlen (s1.ptr) + strlen (s2.ptr) + sizeof format);
+    YY_CAST (char *, malloc (strlen (s1.ptr) + strlen (s2.ptr) + sizeof format));
   sprintf (value, format, s1.ptr, s2.ptr);
   return value;
 }
@@ -601,7 +604,7 @@ stack2: 'a' ;
 static int
 yylex (void)
 {
-  yylval.node = (count_node*) malloc (sizeof *yylval.node);
+  yylval.node = YY_CAST (count_node*, malloc (sizeof *yylval.node));
   if (!yylval.node)
     {
       fprintf (stderr, "Test inconclusive.\n");
@@ -1118,7 +1121,7 @@ change_lookahead:
 
 ]AT_YYERROR_DEFINE[
 ]AT_YYLEX_DEFINE(["ab"],
-                 [yylval.value = (char) (res + 'A' - 'a')])[
+                 [yylval.value = YY_CAST (char, res + 'A' - 'a')])[
 
 static void
 print_lookahead (char const *reduction)
@@ -1319,10 +1322,10 @@ yylex (void)
 {
   static char const input[] = "abcdddd";
   static int toknum = 0;
-  assert (toknum < (int) sizeof input);
+  assert (toknum < YY_CAST (int, sizeof input));
   yylloc.first_line = yylloc.last_line = 1;
   yylloc.first_column = yylloc.last_column = toknum + 1;
-  yylval.value = (char) (input[toknum] + 'A' - 'a');
+  yylval.value = YY_CAST (char, input[toknum] + 'A' - 'a');
   return input[toknum++];
 }
 
@@ -1349,7 +1352,7 @@ print_lookahead (char const *reduction)
 static char
 merge (union YYSTYPE s1, union YYSTYPE s2)
 {
-  return (char) (s1.value + s2.value);
+  return YY_CAST (char, s1.value + s2.value);
 }
 
 int
@@ -1577,7 +1580,7 @@ yylex (YYSTYPE *lvalp, YYLTYPE *llocp)
 {
   static char const input[] = "ab";
   static int toknum = 0;
-  assert (toknum < (int) sizeof input);
+  assert (toknum < YY_CAST (int, sizeof input));
   lvalp->dummy = 0;
   llocp->first_line = llocp->last_line = 2;
   llocp->first_column = toknum + 1;

tests/headers.at

@@ -322,6 +322,7 @@ AT_PERL_CHECK([[-n -0777 -e '
       |YYPUSH_MORE(?:_DEFINED)?
       |YYUSE
       |YY_ATTRIBUTE(?:_PURE|_UNUSED)
+      |YY(?:_REINTERPRET)?_CAST
       |YY_CONSTEXPR
       |YY_COPY
       |YY_CPLUSPLUS

tests/torture.at

@@ -446,7 +446,7 @@ get_args (int argc, const char **argv)
   assert (0 <= res);
   assert (res <= INT_MAX);
   assert (errno != ERANGE);
-  return (int) res;
+  return YY_CAST (int, res);
 }
 
 int

tests/types.at

@@ -166,7 +166,7 @@ m4_foreach([b4_skel], [[yacc.c], [glr.c], [lalr1.cc], [glr.cc]],
           [if (res)
              {
                AT_VAL.ival = (res - '0') * 10;
-               AT_VAL.fval = (float) (res - '0') / 10.f;
+               AT_VAL.fval = YY_CAST (float, res - '0') / 10.f;
              }],
           [30 0.3])
 
@@ -197,7 +197,7 @@ m4_foreach([b4_skel], [[yacc.c], [glr.c], [lalr1.cc], [glr.cc]],
           ["12"],
           [if (res)
              {
-               AT_VAL.up = (struct u *) malloc (sizeof *AT_VAL.up);
+               AT_VAL.up = YY_CAST (struct u *, malloc (sizeof *AT_VAL.up));
                assert (AT_VAL.up);
                AT_VAL.up->ival = res - '0';
              }