C++ upkeep.

TXR's support for compiling as C++ pays off:  C++ compiler finds
serious bugs introduced in August 2 ("Big switch to reentrant lexing
and parsing"). The yyerror function was being misused; some of
the calls reversed the scanner and parser arguments. Since one
of the two parameters is void *, this reversal wasn't caught.

* parser.l (yyerror): Fix first two arguments being
reversed.
(num_esc): Change previously correct call to yyerror to follow reversed
arguments, so that it stays correct.

* parser.y (%parse-param): Change order of these directives
so that the scnr parameter is before the parser parameter.
This causes the yacc-generated calls to yyerror to have
the arguments in the correct order.  It also has the
effect of changing the signature of yyparse, reversing its parameters.
(parse): Update call to yyparse to new argument order.

* parser.h (yyparse): Declaration removed.
(yyerror): Declaration updated.

* regex.c (regex_kind_t): New enum typedef.
(struct regex): Use regex_kind_t rather than an enum
inside the struct, which has different scoping rules
under C++.

* txr.c (get_self_path): Fix signed/unsigned warning.

6 files changed, 42 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 498251e2..fb23e8e8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,37 @@
 2014-10-14  Kaz Kylheku  <kaz@kylheku.com>
 
+	C++ upkeep.
+
+	TXR's support for compiling as C++ pays off:  C++ compiler finds
+	serious bugs introduced in August 2 ("Big switch to reentrant lexing
+	and parsing"). The yyerror function was being misused; some of
+	the calls reversed the scanner and parser arguments. Since one
+	of the two parameters is void *, this reversal wasn't caught.
+
+	* parser.l (yyerror): Fix first two arguments being
+	reversed.
+	(num_esc): Change previously correct call to yyerror to follow reversed
+	arguments, so that it stays correct.
+
+	* parser.y (%parse-param): Change order of these directives
+	so that the scnr parameter is before the parser parameter.
+	This causes the yacc-generated calls to yyerror to have
+	the arguments in the correct order.  It also has the
+	effect of changing the signature of yyparse, reversing its parameters.
+	(parse): Update call to yyparse to new argument order.
+
+	* parser.h (yyparse): Declaration removed.
+	(yyerror): Declaration updated.
+
+	* regex.c (regex_kind_t): New enum typedef.
+	(struct regex): Use regex_kind_t rather than an enum
+	inside the struct, which has different scoping rules
+	under C++.
+
+	* txr.c (get_self_path): Fix signed/unsigned warning.
+
+2014-10-14  Kaz Kylheku  <kaz@kylheku.com>
+
 	* txr.1: Round of fixes.
 
 2014-10-13  Kaz Kylheku  <kaz@kylheku.com>
diff --git a/parser.h b/parser.h
index 305b8d7b..bb85d01c 100644
--- a/parser.h
+++ b/parser.h
@@ -36,8 +36,7 @@ typedef struct {
 
 extern const wchar_t *spec_file;
 extern val form_to_ln_hash;
-int yyparse(parser_t *, void *scanner);
-void yyerror(parser_t *, void *scanner, const char *s);
+void yyerror(void *scanner, parser_t *, const char *s);
 void yyerr(void *scanner, const char *s);
 void yyerrorf(void *scanner, val s, ...);
 void yybadtoken(parser_t *, int tok, val context);
diff --git a/parser.l b/parser.l
index 66ccb4bd..d59955b7 100644
--- a/parser.l
+++ b/parser.l
@@ -78,7 +78,7 @@ int yylex_destroy(void)
 int yyget_column(void *);
 void yyset_column (int  column_no , yyscan_t yyscanner);
 
-void yyerror(parser_t *parser, void *scanner, const char *s)
+void yyerror(void *scanner, parser_t *parser, const char *s)
 {
   yyerrorf(scanner, lit("~a"), string_utf8(s), nao);
   if (parser->prepared_msg) {
@@ -141,13 +141,13 @@ static wchar_t num_esc(void *scn, char *num)
 {
   if (num[0] == 'x') {
     if (strlen(num) > 7)
-      yyerror(yyget_extra(scn), scn, "too many digits in hex character escape");
+      yyerror(scn, yyget_extra(scn), "too many digits in hex character escape");
     return strtol(num + 1, 0, 16);
   } else {
     if (num[0] == 'o')
       num++;
     if (strlen(num) > 8)
-      yyerror(yyget_extra(scn), scn, "too many digits in octal character escape");
+      yyerror(scn, yyget_extra(scn), "too many digits in octal character escape");
     return strtol(num, 0, 8);
   }
 }
diff --git a/parser.y b/parser.y
index d9b4f241..00bb15cf 100644
--- a/parser.y
+++ b/parser.y
@@ -72,8 +72,8 @@ int yylex(union YYSTYPE *, void *scanner);
 %}
 
 %pure-parser
-%parse-param{parser_t *parser}
 %parse-param{void *scnr}
+%parse-param{parser_t *parser}
 %lex-param{void *scnr}
 
 %union {
@@ -1365,7 +1365,7 @@ int parse(val stream, val name, parser_t *parser)
 
   yyset_extra(parser, parser->scanner);
 
-  res = yyparse(parser, parser->scanner);
+  res = yyparse(parser->scanner, parser);
 
   yylex_destroy(parser->scanner);
 
diff --git a/regex.c b/regex.c
index e4dfee4d..87fad93e 100644
--- a/regex.c
+++ b/regex.c
@@ -56,8 +56,10 @@ typedef struct nfa {
   nfa_state_t *accept;
 } nfa_t;
 
+typedef enum { REGEX_NFA, REGEX_DV } regex_kind_t;
+
 typedef struct regex {
-  enum { REGEX_NFA, REGEX_DV } kind;
+  regex_kind_t kind;
   union {
     struct nfa nfa;
     val dv;
diff --git a/txr.c b/txr.c
index b9c11e5f..fe2ce3da 100644
--- a/txr.c
+++ b/txr.c
@@ -180,7 +180,7 @@ static val get_self_path(void)
   char self[PATH_MAX] = { 0 };
   int nchar = readlink("/proc/self/exe", self, sizeof self);
 
-  if (nchar < 0 || nchar >= sizeof self)
+  if (nchar < 0 || nchar >= (int) sizeof self)
     return nil;
   return string_utf8(self);
 }