integration tests in src/bin/ run forever with --features='seccomp'

[kentfredric]

This may not be important, but it looks a bit spicy:

     Running target/debug/deps/brotli-69525ecfc53fa34c

running 93 tests
1 Iterations; Time 0.002088729
test integration_tests::test_10x_10y_one_out_byte ... ok
1 Iterations; Time 0.002077081
test integration_tests::test_10x_10y_byte_by_byte ... ok

thread 'integration_tests::test_10x_10y' has overflowed its stack
fatal runtime error: stack overflow

thread 'integration_tests::test_64x' has overflowed its stack
fatal runtime error: stack overflow
1 Iterations; Time 0.625489011
test integration_tests::test_alice1 ... ok

thread 'integration_tests::test_alice29' has overflowed its stack
fatal runtime error: stack overflow

thread 'integration_tests::test_1024k' has overflowed its stack
fatal runtime error: stack overflow
test integration_tests::test_1024k ... test integration_tests::test_1024k has been running for over 60 seconds
test integration_tests::test_10x_10y ... test integration_tests::test_10x_10y has been running for over 60 seconds
test integration_tests::test_64x ... test integration_tests::test_64x has been running for over 60 seconds
test integration_tests::test_alice29 ... test integration_tests::test_alice29 has been running for over 60

Poking at the instance with strace shows one process waiting with

futex(5fe7288da9c, FUTEX_WAIT_PRIVATE, 0, NULL

And its parent is doing

wait4(17733,

So there seems to be some sort of thread mess happening.

And annoyingly, when you invoke the program with

 target/debug/deps/brotli-69525ecfc53fa34c --test-threads 1

It panics after printing:

running 93 tests
test integration_tests::test_1024k ... 

And you get a nice notice in dmesg:

[3552418.530377] audit: type=1326 audit(1582361087.220:47): auid=1000 uid=1000 gid=1000 ses=2 pid=17945 comm="integration_tes" exe="/tmp/rust-brotli/target/debug/deps/brotli-69525ecfc53fa34c" sig=9 arch=c000003e syscall=202 compat=0 ip=0x7fcbea49a60a code=0x0

Running with strace and --test-threads=2 gives this:

strace -f target/debug/deps/brotli-2390a973bcc44b8e --test-threads=2

execve("target/debug/deps/brotli-2390a973bcc44b8e", ["target/debug/deps/brotli-2390a97"..., "--test-threads", "2"], 0x7ffe89314108 /* 112 vars */) = 0
brk(NULL)                               = 0x55e6e8892000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=369771, ...}) = 0
mmap(NULL, 369771, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f9088bc4000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0000\21\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=18520, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088bc2000
mmap(NULL, 20752, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f9088bbc000
mmap(0x7f9088bbd000, 8192, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0x7f9088bbd000
mmap(0x7f9088bbf000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f9088bbf000
mmap(0x7f9088bc0000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f9088bc0000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0pm\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=2788552, ...}) = 0
mmap(NULL, 140448, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f9088b99000
mmap(0x7f9088b9f000, 73728, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6000) = 0x7f9088b9f000
mmap(0x7f9088bb1000, 20480, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x18000) = 0x7f9088bb1000
mmap(0x7f9088bb6000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c000) = 0x7f9088bb6000
mmap(0x7f9088bb8000, 13472, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f9088bb8000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/libgcc_s.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0203\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=100624, ...}) = 0
mmap(NULL, 103504, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f9088b7f000
mmap(0x7f9088b82000, 69632, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f9088b82000
mmap(0x7f9088b93000, 16384, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x14000) = 0x7f9088b93000
mmap(0x7f9088b97000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17000) = 0x7f9088b97000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0000@\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1889072, ...}) = 0
mmap(NULL, 1902152, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f90889ae000
mmap(0x7f90889d0000, 1417216, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x22000) = 0x7f90889d0000
mmap(0x7f9088b2a000, 307200, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17c000) = 0x7f9088b2a000
mmap(0x7f9088b75000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c6000) = 0x7f9088b75000
mmap(0x7f9088b7b000, 13896, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f9088b7b000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libm.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\340\321\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1321152, ...}) = 0
mmap(NULL, 1323264, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f908886a000
mmap(0x7f9088877000, 638976, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xd000) = 0x7f9088877000
mmap(0x7f9088913000, 626688, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xa9000) = 0x7f9088913000
mmap(0x7f90889ac000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x141000) = 0x7f90889ac000
close(3)                                = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088868000
arch_prctl(ARCH_SET_FS, 0x7f9088869380) = 0
mprotect(0x7f9088b75000, 16384, PROT_READ) = 0
mprotect(0x7f90889ac000, 4096, PROT_READ) = 0
mprotect(0x7f9088b97000, 4096, PROT_READ) = 0
mprotect(0x7f9088bb6000, 4096, PROT_READ) = 0
mprotect(0x7f9088bc0000, 4096, PROT_READ) = 0
mprotect(0x55e6e8218000, 135168, PROT_READ) = 0
mprotect(0x7f9088c47000, 4096, PROT_READ) = 0
munmap(0x7f9088bc4000, 369771)          = 0
set_tid_address(0x7f9088869650)         = 19338
set_robust_list(0x7f9088869660, 24)     = 0
rt_sigaction(SIGRTMIN, {sa_handler=0x7f9088b9f6e0, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f9088bae2f0}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {sa_handler=0x7f9088b9f7b0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f9088bae2f0}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
rt_sigaction(SIGPIPE, {sa_handler=SIG_IGN, sa_mask=[PIPE], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x7f90889e81d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
brk(NULL)                               = 0x55e6e8892000
brk(0x55e6e88b3000)                     = 0x55e6e88b3000
openat(AT_FDCWD, "/proc/self/maps", O_RDONLY|O_CLOEXEC) = 3
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
fstat(3, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
read(3, "55e6e7a3c000-55e6e7a68000 r--p 0"..., 1024) = 1024
read(3, "0010                    /lib64/l"..., 1024) = 1024
read(3, "-p 00014000 08:06 5922514       "..., 1024) = 1024
read(3, "000 08:06 5858076               "..., 1024) = 1024
close(3)                                = 0
sched_getaffinity(19338, 32, [0, 1, 2, 3]) = 8
rt_sigaction(SIGSEGV, {sa_handler=0x55e6e7e37530, sa_mask=[], sa_flags=SA_RESTORER|SA_ONSTACK|SA_SIGINFO, sa_restorer=0x7f9088bae2f0}, NULL, 8) = 0
rt_sigaction(SIGBUS, {sa_handler=0x55e6e7e37530, sa_mask=[], sa_flags=SA_RESTORER|SA_ONSTACK|SA_SIGINFO, sa_restorer=0x7f9088bae2f0}, NULL, 8) = 0
sigaltstack(NULL, {ss_sp=NULL, ss_flags=SS_DISABLE, ss_size=0}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088c1d000
sigaltstack({ss_sp=0x7f9088c1d000, ss_flags=0, ss_size=8192}, NULL) = 0
statx(0, NULL, AT_STATX_SYNC_AS_STAT, STATX_ALL, NULL) = -1 EFAULT (Bad address)
statx(AT_FDCWD, "/home/kent/.terminfo", AT_STATX_SYNC_AS_STAT, STATX_ALL, 0x7ffd282a5eb0) = -1 ENOENT (No such file or directory)
statx(AT_FDCWD, "/etc/terminfo", AT_STATX_SYNC_AS_STAT, STATX_ALL, {stx_mask=STATX_ALL, stx_attributes=0, stx_mode=S_IFDIR|0755, stx_size=4096, ...}) = 0
statx(AT_FDCWD, "/etc/terminfo/r/rxvt-unicode-256color", AT_STATX_SYNC_AS_STAT, STATX_ALL, {stx_mask=STATX_ALL, stx_attributes=0, stx_mode=S_IFREG|0644, stx_size=2226, ...}) = 0
openat(AT_FDCWD, "/etc/terminfo/r/rxvt-unicode-256color", O_RDONLY|O_CLOEXEC) = 3
fcntl(3, F_GETFD)                       = 0x1 (flags FD_CLOEXEC)
read(3, "\32\1N\0\35\0\37\0p\1\34\5rxvt-unicode-256colo"..., 8192) = 2226
getrandom("\x22\x9c\x93\x1c\x7c\x62\xb3\xbc\xfb\x93\x70\xae\x48\x87\xb9\xe0", 16, GRND_NONBLOCK) = 16
close(3)                                = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
write(1, "\nrunning 82 tests\n", 18
running 82 tests
)    = 18
futex(0x7f9088bc10c8, FUTEX_WAKE_PRIVATE, 2147483647) = 0
mmap(NULL, 2101248, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f9088667000
mprotect(0x7f9088668000, 2097152, PROT_READ|PROT_WRITE) = 0
clone(child_stack=0x7f9088866eb0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTIDstrace: Process 19339 attached
, parent_tid=[19339], tls=0x7f9088867700, child_tidptr=0x7f90888679d0) = 19339
[pid 19339] set_robust_list(0x7f90888679e0, 24 <unfinished ...>
[pid 19338] mmap(NULL, 2101248, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0 <unfinished ...>
[pid 19339] <... set_robust_list resumed>) = 0
[pid 19338] <... mmap resumed>)         = 0x7f9088466000
[pid 19339] sigaltstack(NULL,  <unfinished ...>
[pid 19338] mprotect(0x7f9088467000, 2097152, PROT_READ|PROT_WRITE <unfinished ...>
[pid 19339] <... sigaltstack resumed>{ss_sp=NULL, ss_flags=SS_DISABLE, ss_size=0}) = 0
[pid 19338] <... mprotect resumed>)     = 0
[pid 19339] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0 <unfinished ...>
[pid 19338] clone(child_stack=0x7f9088665eb0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID <unfinished ...>
[pid 19339] <... mmap resumed>)         = 0x7f9088c1b000
strace: Process 19340 attached
[pid 19339] sigaltstack({ss_sp=0x7f9088c1b000, ss_flags=0, ss_size=8192},  <unfinished ...>
[pid 19338] <... clone resumed>, parent_tid=[19340], tls=0x7f9088666700, child_tidptr=0x7f90886669d0) = 19340
[pid 19340] set_robust_list(0x7f90886669e0, 24 <unfinished ...>
[pid 19338] futex(0x55e6e8892a98, FUTEX_WAIT_BITSET_PRIVATE, 0, {tv_sec=3553292, tv_nsec=858960840}, FUTEX_BITSET_MATCH_ANY <unfinished ...>
[pid 19339] <... sigaltstack resumed>NULL) = 0
[pid 19340] <... set_robust_list resumed>) = 0
[pid 19339] prctl(PR_SET_NAME, "integration_tes"... <unfinished ...>
[pid 19340] sigaltstack(NULL,  <unfinished ...>
[pid 19339] <... prctl resumed>)        = 0
[pid 19340] <... sigaltstack resumed>{ss_sp=NULL, ss_flags=SS_DISABLE, ss_size=0}) = 0
[pid 19340] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0 <unfinished ...>
[pid 19339] mmap(NULL, 134217728, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE, -1, 0) = 0x7f9080466000
[pid 19340] <... mmap resumed>)         = 0x7f9088c19000
[pid 19339] munmap(0x7f9080466000, 62496768 <unfinished ...>
[pid 19340] sigaltstack({ss_sp=0x7f9088c19000, ss_flags=0, ss_size=8192},  <unfinished ...>
[pid 19339] <... munmap resumed>)       = 0
[pid 19340] <... sigaltstack resumed>NULL) = 0
[pid 19339] munmap(0x7f9088000000, 4612096 <unfinished ...>
[pid 19340] prctl(PR_SET_NAME, "integration_tes"... <unfinished ...>
[pid 19339] <... munmap resumed>)       = 0
[pid 19340] <... prctl resumed>)        = 0
[pid 19339] mprotect(0x7f9084000000, 135168, PROT_READ|PROT_WRITE) = 0
[pid 19340] mmap(NULL, 134217728, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE, -1, 0 <unfinished ...>
[pid 19339] sched_getaffinity(19339, 32,  <unfinished ...>
[pid 19340] <... mmap resumed>)         = 0x7f907c000000
[pid 19339] <... sched_getaffinity resumed>[0, 1, 2, 3]) = 8
[pid 19340] munmap(0x7f9080000000, 67108864 <unfinished ...>
[pid 19339] mmap(NULL, 1052672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0 <unfinished ...>
[pid 19340] <... munmap resumed>)       = 0
[pid 19339] <... mmap resumed>)         = 0x7f9088365000
[pid 19340] mprotect(0x7f907c000000, 135168, PROT_READ|PROT_WRITE) = 0
[pid 19340] sched_getaffinity(19340, 32, [0, 1, 2, 3]) = 8
[pid 19340] mmap(NULL, 209719296, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f906f7ff000
[pid 19340] mmap(NULL, 67112960, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f906b7fe000
[pid 19340] prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT) = 0
[pid 19340] --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_ACCERR, si_addr=0x7f90884668c8} ---
[pid 19340] write(2, "\nthread '", 9
thread ')   = 9
[pid 19340] write(2, "integration_tests::test_10x_10y", 31integration_tests::test_10x_10y) = 31
[pid 19340] write(2, "' has overflowed its stack\n", 27' has overflowed its stack
) = 27
[pid 19340] write(2, "fatal runtime error: ", 21fatal runtime error: ) = 21
[pid 19340] write(2, "stack overflow", 14stack overflow) = 14
[pid 19340] write(2, "\n", 1
)           = 1
[pid 19340] rt_sigprocmask(SIG_UNBLOCK, [ABRT],  <unfinished ...>) = ?
[pid 19340] +++ killed by SIGKILL +++
[pid 19339] mmap(NULL, 1052672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088264000
[pid 19339] mmap(NULL, 1060864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088161000
[pid 19339] mmap(NULL, 1052672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088060000
[pid 19339] mmap(NULL, 8409088, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f90837fb000
[pid 19339] mprotect(0x7f9084021000, 32768, PROT_READ|PROT_WRITE) = 0
[pid 19339] mmap(NULL, 200704, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9088be8000
[pid 19339] mmap(NULL, 266240, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f908801f000
[pid 19339] mprotect(0x7f9084029000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 19339] mprotect(0x7f908402a000, 8192, PROT_READ|PROT_WRITE) = 0
[pid 19339] mprotect(0x7f908402c000, 57344, PROT_READ|PROT_WRITE) = 0
[pid 19339] munmap(0x7f9088be8000, 200704) = 0
[pid 19339] munmap(0x7f90837fb000, 8409088) = 0
[pid 19339] munmap(0x7f908801f000, 266240) = 0
[pid 19339] mmap(NULL, 209719296, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f905effd000
[pid 19339] mmap(NULL, 67112960, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f905affc000
[pid 19339] prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT) = 0
[pid 19339] --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_ACCERR, si_addr=0x7f9088667628} ---
[pid 19339] write(2, "\nthread '", 9
thread ')   = 9
[pid 19339] write(2, "integration_tests::test_1024k", 29integration_tests::test_1024k) = 29
[pid 19339] write(2, "' has overflowed its stack\n", 27' has overflowed its stack
) = 27
[pid 19339] write(2, "fatal runtime error: ", 21fatal runtime error: ) = 21
[pid 19339] write(2, "stack overflow", 14stack overflow) = 14
[pid 19339] write(2, "\n", 1
)           = 1
[pid 19339] futex(0x7f9088b7ac50, FUTEX_WAIT_PRIVATE, 2, NULL) = ?
[pid 19339] +++ killed by SIGKILL +++

Failing binary attached

brotli-2390a973bcc44b8e.gz

[kentfredric]

( NB: in case you wonder why the checksum changed, the first one was built with --features 'seccomp', and the second was with an added --no-default-features just in case std or something was to blame )