When offset + length == exts->end the code which is shortening the extents is subtracting 0 from length. And it is not optimized out. Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com&gt; --- server/extents.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/server/extents.c b/server/extents.c index d3d1a15ab97c..c422491601f0 100644 --- a/server/extents.c +++ b/server/extents.c @@ -168,7 +168,7 @@ nbdkit_add_extent (struct nbdkit_extents *exts, return 0; /* Shorten extents that overlap the end of the range. */ - if (offset + length >= exts->end) { + if (offset + length > exts->end) { overlap = offset + length - exts->end; length -= overlap; }