never say "error on line -1"

diff --git a/parse.yacc b/parse.yacc
index 12d0cb92ab7dae8346f9142881e4118b82a08cd4..7a7cfd8e5f17172699d38fc1c11ec2242f2fac61 100644 (file)
--- a/parse.yacc
+++ b/parse.yacc
@@ -147,10 +147,10 @@ void yyerror(s)
 {
     /* save the line the first error occured on */
     if (errorlineno == -1)
-       errorlineno = sudolineno - 1;
+       errorlineno = sudolineno ? sudolineno - 1 : 0;
 #ifndef TRACELEXER
     (void) fprintf(stderr, ">>> sudoers file: %s, line %d <<<\n", s,
-       sudolineno - 1);
+       sudolineno ? sudolineno - 1 : 0);
 #else
     (void) fprintf(stderr, "<*> ");
 #endif