When running with UndefinedBehaviorSanitizer, the tests produce the following error:
radix-tree.c:836:30: runtime error: shift exponent 18446744073709551613 is too large for 64-bit type 'unsigned long' (That's a negative shift exponent represented as an unsigned long.) Even though the value is discarded in those cases, it's still undefined behavior; see the C99 standard, section 6.5.7, paragraph three: "If the value of the right operand is negative [...] the behavior is undefined." Signed-off-by: Adam Buchbinder <[email protected]> --- radix-tree.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/radix-tree.c b/radix-tree.c index 4f295fc..7457944 100644 --- a/radix-tree.c +++ b/radix-tree.c @@ -833,10 +833,10 @@ int radix_tree_tagged(struct radix_tree_root *root, unsigned int tag) static unsigned long __maxindex(unsigned int height) { unsigned int tmp = height * RADIX_TREE_MAP_SHIFT; - unsigned long index = (~0UL >> (RADIX_TREE_INDEX_BITS - tmp - 1)) >> 1; + unsigned long index = ~0UL; - if (tmp >= RADIX_TREE_INDEX_BITS) - index = ~0UL; + if (tmp < RADIX_TREE_INDEX_BITS) + index = (index >> (RADIX_TREE_INDEX_BITS - tmp - 1)) >> 1; return index; } -- 2.0.0.526.g5318336 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
