When backporting BACKPORT-5649 and BACKPORT-5644, I found the syscall test on 4.0 is always failing even without the backported changes.
The test generates a stderr.txt file with a bunch of close calls without open at the start of the file, which causes the test to fail.
Here's the output of the stderr.txt:
close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 close(3) = 0 --------------wiredtiger_open pwrite64(3, "WiredTiger lock file\n", 21, 0) = 21 pwrite64(4, "WiredTiger\nWiredTiger 3.1.1: (Ju"..., 45, 0) = 45 fdatasync(4) = 0 close(4) = 0 pwrite64(4, "# Do not modify this file.\n#\n# W"..., 347, 0) = 347 fdatasync(4) = 0 close(4) = 0 rename("./WiredTiger.basecfg.set", "./WiredTiger.basecfg") = 0 fdatasync(4) = 0 close(4) = 0 fdatasync(5) = 0 close(5) = 0 pwrite64(4, "A\330\1\0\1\0\0\0\330\10#\267\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 4096, 0) = 4096 fdatasync(4) = 0 close(4) = 0 ftruncate(4, 4096) = 0 pwrite64(5, "WiredTiger version string\nWiredT"..., 913, 0) = 913 fdatasync(5) = 0 close(5) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(5) = 0 close(5) = 0 close(5) = 0 close(5) = 0 close(5) = 0 pwrite64(5, "WiredTiger version string\nWiredT"..., 1013, 0) = 1013 fdatasync(5) = 0 close(5) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(5) = 0 close(5) = 0 fdatasync(6) = 0 close(6) = 0 pwrite64(5, "A\330\1\0\1\0\0\0\330\10#\267\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 4096, 0) = 4096 fdatasync(5) = 0 close(5) = 0 ftruncate(5, 4096) = 0 close(6) = 0 pwrite64(4, "\0\0\0\0\0\0\0\0\1\0\0\0\0\0\0\0h\3\0\0\2\0\0\0\7\4\0\0\0\20\0\0"..., 4096, 4096) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\2\0\0\0\0\0\0\0003\0\0\0\2\0\0\0\6\0\0\0\0\20\0\0"..., 4096, 8192) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0002\0\0\0\n\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 12288) = 4096 close(6) = 0 pwrite64(6, "WiredTiger version string\nWiredT"..., 1068, 0) = 1068 fdatasync(6) = 0 close(6) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(6) = 0 close(6) = 0 --------------open_session --------------create fdatasync(7) = 0 close(7) = 0 pwrite64(6, "A\330\1\0\1\0\0\0\330\10#\267\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 4096, 0) = 4096 fdatasync(6) = 0 close(6) = 0 ftruncate(6, 4096) = 0 close(7) = 0 pwrite64(4, "\0\0\0\0\0\0\0\0\3\0\0\0\0\0\0\0<\7\0\0\10\0\0\0\7\4\0\0\0\20\0\0"..., 4096, 16384) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\4\0\0\0\0\0\0\0003\0\0\0\2\0\0\0\6\0\0\0\0\20\0\0"..., 4096, 20480) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0003\0\0\0\v\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 24576) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0003\0\0\0\v\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 28672) = 4096 close(7) = 0 pwrite64(7, "WiredTiger version string\nWiredT"..., 1076, 0) = 1076 fdatasync(7) = 0 close(7) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(7) = 0 close(7) = 0 --------------rename ftruncate(6, 4096) = 0 close(6) = 0 rename("./hello.wt", "./world.wt") = 0 close(6) = 0 pwrite64(4, "\0\0\0\0\0\0\0\0\5\0\0\0\0\0\0\0<\7\0\0\10\0\0\0\7\4\0\0\0\20\0\0"..., 4096, 4096) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\6\0\0\0\0\0\0\0003\0\0\0\2\0\0\0\6\0\0\0\0\20\0\0"..., 4096, 8192) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0002\0\0\0\n\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 12288) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0004\0\0\0\f\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 32768) = 4096 close(6) = 0 pwrite64(6, "WiredTiger version string\nWiredT"..., 1076, 0) = 1076 fdatasync(6) = 0 close(6) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(6) = 0 close(6) = 0 --------------drop close(6) = 0 pwrite64(4, "\0\0\0\0\0\0\0\0\7\0\0\0\0\0\0\0h\3\0\0\2\0\0\0\7\4\0\0\0\20\0\0"..., 4096, 16384) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\10\0\0\0\0\0\0\0003\0\0\0\2\0\0\0\6\0\0\0\0\20\0\0"..., 4096, 20480) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0003\0\0\0\v\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 24576) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0=\0\0\0\25\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 28672) = 4096 close(6) = 0 pwrite64(6, "WiredTiger version string\nWiredT"..., 1076, 0) = 1076 fdatasync(6) = 0 close(6) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(6) = 0 close(6) = 0 --------------WT_CONNECTION::close close(6) = 0 pwrite64(4, "\0\0\0\0\0\0\0\0\t\0\0\0\0\0\0\0h\3\0\0\2\0\0\0\7\4\0\0\0\20\0\0"..., 4096, 32768) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\n\0\0\0\0\0\0\0003\0\0\0\2\0\0\0\6\0\0\0\0\20\0\0"..., 4096, 4096) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0007\0\0\0\17\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 8192) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0009\0\0\0\21\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 12288) = 4096 close(6) = 0 pwrite64(6, "WiredTiger version string\nWiredT"..., 1077, 0) = 1077 fdatasync(6) = 0 close(6) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(6) = 0 close(6) = 0 ftruncate(5, 4096) = 0 close(5) = 0 close(5) = 0 pwrite64(4, "\0\0\0\0\0\0\0\0\v\0\0\0\0\0\0\0003\0\0\0\2\0\0\0\6\0\0\0\0\20\0\0"..., 4096, 16384) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0008\0\0\0\20\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 20480) = 4096 pwrite64(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0008\0\0\0\20\0\0\0\1\0\0\0\0\20\0\0"..., 4096, 24576) = 4096 close(5) = 0 pwrite64(5, "WiredTiger version string\nWiredT"..., 1077, 0) = 1077 fdatasync(5) = 0 close(5) = 0 rename("./WiredTiger.turtle.set", "./WiredTiger.turtle") = 0 fdatasync(5) = 0 close(5) = 0 ftruncate(4, 36864) = 0 close(4) = 0 close(3) = 0 +++ exited with 0 +++