On 03/19/2015 02:05 PM, Jakub Jelinek wrote:
Though, a question is if we do (or, if we don't and should) reject say constexpr char s[] = "abc"; constexpr int j = 4; constexpr char c = *(&s[j] - 2); because there was out of bound access in there.
I don't see an out-of-bound access in this example; taking the address of one-past-the-end is OK as long as you don't try to access through it.
Unfortunately we reject even that (regardless the patch), and yeah, it's because of how POINTER_PLUS_EXPR uses sizetype as a type of the second operand.
This seems like something to fix in this patch.
+ tree t = fold_convert_loc (loc, TREE_TYPE (op01), + TREE_OPERAND (op00, 1)); + t = size_binop_loc (loc, PLUS_EXPR, op01, t);
This seems to be assuming that the elements are size 1. Jason
