make usage of the new parser easier to configure

tools/qfcc/acconfig.h

@@ -4,5 +4,9 @@
 #ifndef __config_h_
 #define __config_h_
 @TOP@
+
+/* Define this if you want to use the new parser */
+#undef NEW_PARSER
+
 @BOTTOM@
 #endif // __config_h_

tools/qfcc/configure.in

@@ -97,6 +97,13 @@ if test "x$HAVE_QF" != xno; then
 	)
 fi
 
+AC_ARG_ENABLE(new-parser,
+	[  --enable-new-parser         enable the new parser. not yet fully functional])
+
+if test "x$enable_new_parser" = "xyes"; then
+	AC_DEFINE(NEW_PARSER)
+fi
+AM_CONDITIONAL(NEW_PARSER, test "x$enable_new_parser" = "xyes")
 
 if test "x$HAVE_QF" = xno; then
 	echo '***'

tools/qfcc/source/Makefile.am

@@ -33,5 +33,9 @@ YFLAGS = -d
 
 bin_PROGRAMS=	qfcc
 
-qfcc_SOURCES=	cmdlib.c pr_comp.c pr_def.c pr_imm.c pr_lex.c pr_opcode.c qfcc.c #qc-parse.y qc-lex.l expr.c
+if NEW_PARSER
+qfcc_SOURCES=	cmdlib.c pr_comp.c pr_def.c pr_imm.c pr_lex.c pr_opcode.c qfcc.c qc-parse.y qc-lex.l expr.c
+else
+qfcc_SOURCES=	cmdlib.c pr_comp.c pr_def.c pr_imm.c pr_lex.c pr_opcode.c qfcc.c
+endif
 qfcc_LDADD=	-lQFutil

tools/qfcc/source/qfcc.c

@@ -903,7 +903,7 @@ Options: \n\
 
 	// compile all the files
 	while ((src = COM_Parse (src))) {
-#if 0
+#ifdef NEW_PARSER
 		extern FILE *yyin;
 		int yyparse(void);
 		extern int lineno;