[Copied from IRC chat]
The fix is wrong - this commit broke cursor tracking: 37081325f7356587c5e6 "ITS#8406 fix xcursors after cursor_del"
Demo: mtest_rand -v -f700 -i3 -p0x1000 -r1276664687.3 It sets C_DEL on the wrong xcursor, one which is at a different key than the deleted key. Like this: put key1, data1 put[cursor] key2, data2 del key1, data1 Now [cursor].mx_cursor has C_DEL.
This also breaks - probably the same bug: mtest_rand -v -c7 -f326 -p0x800 -r2712746413