hb-blob.cc:107: Undefined Behaviour ?

[dcb314]

[hb-blob.cc:107]: (warning) Invalid test for overflow 'data+length<data'. Condition is always false unless there is overflow, and overflow is Undefined Behaviour.

data + length < data /* overflows */ ||

[behdad]

Good point. Thanks. Is unsigned-int overflow undefined as well? Do you have suggested replacement? How about:

(uintptr_t)-1 - (uintptr_t) data > length

[dcb314]

Is unsigned-int overflow undefined as well?

No. See

http://stackoverflow.com/questions/18195715/why-is-unsigned-integer-overflow-defined-behavior-but-signed-integer-overflow-is

Do you have suggested replacement?

The test for overflow looks mostly pointless to me. Suggest remove.

[behdad]

The test for overflow looks mostly pointless to me. Suggest remove.

Good point. The input must be valid. However, this was NOT the case in one incident, and that's how the code was introduced. But I believe the 2GB check handles that already. See:

7d5e761