The UBSAN builder found the following error:
[2021/07/01 00:28:14.872] FAIL: test_wt3338_partial_update [2021/07/01 00:28:14.872] ================================ [2021/07/01 00:28:14.872] ../../../test/csuite/wt3338_partial_update/main.c:129:12: runtime error: null pointer passed as argument 1, which is declared to never be null [2021/07/01 00:28:14.872] /usr/include/string.h:60:62: note: nonnull attribute specified here [2021/07/01 00:28:14.872] #0 0x42540f in slow_apply_api /data/mci/f7c212376a3c6a98bc4e4be5292cf0be/wiredtiger/build_posix/test/csuite/../../../test/csuite/wt3338_partial_update/main.c:129:5 [2021/07/01 00:28:14.872] #1 0x4236f9 in modify_run /data/mci/f7c212376a3c6a98bc4e4be5292cf0be/wiredtiger/build_posix/test/csuite/../../../test/csuite/wt3338_partial_update/main.c:297:13 [2021/07/01 00:28:14.872] #2 0x4233d2 in main /data/mci/f7c212376a3c6a98bc4e4be5292cf0be/wiredtiger/build_posix/test/csuite/../../../test/csuite/wt3338_partial_update/main.c:341:5 [2021/07/01 00:28:14.872] #3 0x7fb7c90aebf6 in __libc_start_main /build/glibc-S9d2JN/glibc-2.27/csu/../csu/libc-start.c:310 [2021/07/01 00:28:14.872] #4 0x403909 in _start (/data/mci/f7c212376a3c6a98bc4e4be5292cf0be/wiredtiger/build_posix/test/csuite/test_wt3338_partial_update+0x403909) [2021/07/01 00:28:14.872] FAIL test_wt3338_partial_update (exit status: 1)
The failing code is as follows:
memset((uint8_t *)ta->mem + ta->size, 0xff, ta->memsize - ta->size);
A fix similar to the one in WT-7744 should work here.