More type safety, with help from C++ compiler.

* parser.h (scanner_t): New typedef. Cleverly, we use
yyguts_t as the basis for this, which pays off in
a few places, getting rid of conversions.
(parser_t): scanner member redeclared to scanner_t *.
(yyerror, yyerr, yyerrof, end_of_regex, end_of_char):
Declarations updated.

* parser.l (yyerror, yyerrorf, num_esc): scanner argument becomes
scanner_t * instead of void *.
(yyscanner): Occurrences replaced by yyg: why should we
refer to the type-unsafe void *yyscanner, when we know that
in the middle of the yylex function we have the properly
typed yyguts_t *yyg.
(end_of_regex, end_of_char): Argument changes to scanner_t * and name
strategically changes to yyg, eliminating the local variable and cast.

* parser.y (sym_helper): scanner argument becomes
scanner_t * instead of void *.
(%parse-param}: void *scnr becomes scanner_t *scnr.
(define-transform, yybadtoken): Use scanner_t * instead of void *.
(parse): Since yylex_init takes a void **, we use it to initialize
a local void *, and then assign it to the structure member.

1 files changed, 8 insertions, 6 deletions

diff --git a/parser.h b/parser.h
index bb85d01c..532fbfb1 100644
--- a/parser.h
+++ b/parser.h
@@ -24,6 +24,8 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+typedef struct yyguts_t scanner_t;
+
 typedef struct {
   cnum lineno;
   int errors;
@@ -31,17 +33,17 @@ typedef struct {
   val name;
   val prepared_msg;
   val syntax_tree;
-  void *scanner;
+  scanner_t *scanner;
 } parser_t;
 
 extern const wchar_t *spec_file;
 extern val form_to_ln_hash;
-void yyerror(void *scanner, parser_t *, const char *s);
-void yyerr(void *scanner, const char *s);
-void yyerrorf(void *scanner, val s, ...);
+void yyerror(scanner_t *scanner, parser_t *, const char *s);
+void yyerr(scanner_t *scanner, const char *s);
+void yyerrorf(scanner_t *scanner, val s, ...);
 void yybadtoken(parser_t *, int tok, val context);
-void end_of_regex(void *scanner);
-void end_of_char(void *scanner);
+void end_of_regex(scanner_t *scanner);
+void end_of_char(scanner_t *scanner);
 int yylex_init(void **pscanner);
 int yylex_destroy(void *scanner);
 parser_t *yyget_extra(void *scanner);