Fixed a bug in FuncStrAt. New shortcut function GenLiteral0().

git-svn-id: svn://svn.cc65.org/cc65/trunk@3605 b7a2c559-68d2-44c3-8de9-860c34a00d81

src/ca65/expr.h

@@ -79,6 +79,9 @@ ExprNode* SimplifyExpr (ExprNode* Expr, const struct ExprDesc* D);
 ExprNode* GenLiteralExpr (long Val);
 /* Return an expression tree that encodes the given literal value */
 
+ExprNode* GenLiteral0 (void);
+/* Return an expression tree that encodes the the number zero */
+
 ExprNode* GenSymExpr (struct SymEntry* Sym);
 /* Return an expression node that encodes the given symbol */