gcc/ChangeLog:
PR c/71699
* fold-const.c (tree_binary_nonzero_warnv_p): Allow
pointer addition to also be considered nonzero.
---
gcc/fold-const.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 3b9500d..eda713e 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -13200,16 +13200,22 @@ tree_binary_nonzero_warnv_p (enum tree_code code,
{
case POINTER_PLUS_EXPR:
case PLUS_EXPR:
- if (ANY_INTEGRAL_TYPE_P (type) && TYPE_OVERFLOW_UNDEFINED (type))
+ if ((ANY_INTEGRAL_TYPE_P (type) && TYPE_OVERFLOW_UNDEFINED (type))
+ || POINTER_TYPE_P (type))
{
+ /* Pointers are always nonnegative, check integers. */
+ if (ANY_INTEGRAL_TYPE_P (type))
+ {
+ sub_strict_overflow_p = false;
+ if (!tree_expr_nonnegative_warnv_p (op0,
+ &sub_strict_overflow_p)
+ || !tree_expr_nonnegative_warnv_p (op1,
+ &sub_strict_overflow_p))
+ return false;
+ }
/* With the presence of negative values it is hard
to say something. */
- sub_strict_overflow_p = false;
- if (!tree_expr_nonnegative_warnv_p (op0,
- &sub_strict_overflow_p)
- || !tree_expr_nonnegative_warnv_p (op1,
- &sub_strict_overflow_p))
- return false;
+
/* One of operands must be positive and the other non-negative. */
/* We don't set *STRICT_OVERFLOW_P here: even if this value
overflows, on a twos-complement machine the sum of two
--
2.8.3
