Jeff King <peff@xxxxxxxx> writes: > There are other variants, too: > > - we could use malloc(1) versus xmalloc(0). Maybe more > readable/obvious? But also potentially allocates an extra byte when > the platform malloc(0) would not need to. > > - we could return a non-NULL "ptr" without shrinking it at all (nor > allocating anything new). This is perfectly legal, and the > underlying realloc() would still know the original size if anybody > ever asked to grow it back again. > > I have to admit I don't overly care between them. I don't either. I admit that the latter I didn't think of---it feels tricky and harder to reason about than any other variants. > I suspect one of the > reasons we never ran into this 15-year-old bug is that it's quite hard > to convince Git to call realloc(0) in the first place. I only saw it > when investigating a bug in another series, and there the problem turned > out to be reading garbage bytes off the end of a buffer (which we > interpreted as a serialized ewah bitmap which happened to have a zero in > its length byte). Thanks.
