toolchain/55014: nbctfmerge hung

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         55014
>Category:       toolchain
>Synopsis:       nbctfmerge hung
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    toolchain-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Feb 25 11:30:00 +0000 2020
>Originator:     Andreas Gustafsson
>Release:        NetBSD 9.0
>Organization:

>Environment:
System: NetBSD
Architecture: x86_64
Machine: amd64
>Description:

Building -current/amd64 from source date 2020.02.25.00.42.12 on
9.0/amd64 on a 12-core host, a nbctfprocess hung, with ps showing
a "parked" state:

$ ps -glaxwd
 UID   PID  PPID   CPU PRI NI    VSZ    RSS WCHAN   STAT TTY         TIME COMMAND
[...]
 101 20724 26840     0  33 10  58480   5756 parked  SNl  ?        0:00.02 |                                                   `-- /tmp/bracket/build/2020.02.25.00.42.12-amd64-baremetal/tools/bin/nbctfmerge -t -g -L VERSION -o less main.o screen.o brac.o ch.o

gdb shows:

guido$ gdb /tmp/bracket/build/2020.02.25.00.42.12-amd64-baremetal/tools/bin/nbctfmerge 
GNU gdb (GDB) 8.3
[...]
Reading symbols from /tmp/bracket/build/2020.02.25.00.42.12-amd64-baremetal/tools/bin/nbctfmerge...
(No debugging symbols found in /tmp/bracket/build/2020.02.25.00.42.12-amd64-baremetal/tools/bin/nbctfmerge)
(gdb) attach 20724
Attaching to program: /tmp/bracket/build/2020.02.25.00.42.12-amd64-baremetal/tools/bin/nbctfmerge, process 20724
[New LWP 5 of process 20724]
[New LWP 4 of process 20724]
[New LWP 3 of process 20724]
[New LWP 2 of process 20724]
[New LWP 1 of process 20724]
Reading symbols from /usr/lib/librt.so.1...
Reading symbols from /usr/libdata/debug//usr/lib/librt.so.1.1.debug...
Reading symbols from /usr/lib/libz.so.1...
Reading symbols from /usr/libdata/debug//usr/lib/libz.so.1.0.debug...
Reading symbols from /usr/lib/libpthread.so.1...
Reading symbols from /usr/libdata/debug//usr/lib/libpthread.so.1.4.debug...
Reading symbols from /usr/lib/libc.so.12...
Reading symbols from /usr/libdata/debug//usr/lib/libc.so.12.213.debug...
Reading symbols from /usr/libexec/ld.elf_so...
Reading symbols from /usr/libdata/debug//usr/libexec/ld.elf_so.debug...
[Switching to LWP 6 of process 20724]
0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) info threads
  Id   Target Id                 Frame 
* 1    LWP 6 of process 20724 "" 0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
  2    LWP 5 of process 20724 "" 0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
  3    LWP 4 of process 20724 "" 0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
  4    LWP 3 of process 20724 "" 0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
  5    LWP 2 of process 20724 "" 0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
  6    LWP 1 of process 20724 "" 0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) where
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
#1  0x00007ef1c14095a6 in pthread__mutex_lock_slow (ptm=0x624fc0 <wq+32>, ts=0x0) at /usr/src/lib/libpthread/pthread_mutex.c:384
#2  0x00000000004049d5 in worker_thread ()
#3  0x00007ef1c140c072 in pthread__create_tramp (cookie=0x7ef1c1ec5000) at /usr/src/lib/libpthread/pthread.c:592
#4  0x00007ef1c0e87af0 in ?? () from /usr/lib/libc.so.12
#5  0x0000000000000000 in ?? ()
(gdb) t 2
[Switching to thread 2 (LWP 5 of process 20724)]
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) where
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
#1  0x00007ef1c140a71f in pthread_cond_timedwait (cond=0x624ff8 <wq+88>, mutex=0x624fc0 <wq+32>, abstime=0x0) at /usr/src/lib/libpthread/pthread_cond.c:168
#2  0x00000000004049fe in worker_thread ()
#3  0x00007ef1c140c072 in pthread__create_tramp (cookie=0x7ef1c1ec7000) at /usr/src/lib/libpthread/pthread.c:592
#4  0x00007ef1c0e87af0 in ?? () from /usr/lib/libc.so.12
#5  0x0000000000000000 in ?? ()
(gdb) t 3 
[Switching to thread 3 (LWP 4 of process 20724)]
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) where
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
#1  0x00007ef1c140a71f in pthread_cond_timedwait (cond=0x624ff8 <wq+88>, mutex=0x624fc0 <wq+32>, abstime=0x0) at /usr/src/lib/libpthread/pthread_cond.c:168
#2  0x00000000004049fe in worker_thread ()
#3  0x00007ef1c140c072 in pthread__create_tramp (cookie=0x7ef1c1ec9000) at /usr/src/lib/libpthread/pthread.c:592
#4  0x00007ef1c0e87af0 in ?? () from /usr/lib/libc.so.12
#5  0x0000000000000000 in ?? ()
(gdb) t 4
[Switching to thread 4 (LWP 3 of process 20724)]
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) where
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
#1  0x00007ef1c140a71f in pthread_cond_timedwait (cond=0x624ff8 <wq+88>, mutex=0x624fc0 <wq+32>, abstime=0x0) at /usr/src/lib/libpthread/pthread_cond.c:168
#2  0x00000000004049fe in worker_thread ()
#3  0x00007ef1c140c072 in pthread__create_tramp (cookie=0x7ef1c1ecb000) at /usr/src/lib/libpthread/pthread.c:592
#4  0x00007ef1c0e87af0 in ?? () from /usr/lib/libc.so.12
#5  0x0000000000000000 in ?? ()
(gdb) t 5
[Switching to thread 5 (LWP 2 of process 20724)]
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) where
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
#1  0x00007ef1c14095a6 in pthread__mutex_lock_slow (ptm=0x624fc0 <wq+32>, ts=0x0) at /usr/src/lib/libpthread/pthread_mutex.c:384
#2  0x00000000004049d5 in worker_thread ()
#3  0x00007ef1c140c072 in pthread__create_tramp (cookie=0x7ef1c1ecd000) at /usr/src/lib/libpthread/pthread.c:592
#4  0x00007ef1c0e87af0 in ?? () from /usr/lib/libc.so.12
#5  0x0000000000400000 in ?? ()
#6  0x00007ef1c0c00000 in ?? ()
#7  0x0000001003a0efff in ?? ()
#8  0x00007ef1c0a000c0 in ?? ()
#9  0x00000000001fff40 in ?? ()
#10 0x0000000000000000 in ?? ()
(gdb) t 6
[Switching to thread 6 (LWP 1 of process 20724)]
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
(gdb) where
#0  0x00007ef1c0ea1f7a in ___lwp_park60 () from /usr/lib/libc.so.12
#1  0x00007ef1c14095a6 in pthread__mutex_lock_slow (ptm=0x624fc0 <wq+32>, ts=0x0) at /usr/src/lib/libpthread/pthread_mutex.c:384
#2  0x0000000000404738 in merge_ctf_cb ()
#3  0x0000000000406a1d in read_file ()
#4  0x0000000000406ddd in read_ctf ()
#5  0x00000000004056c6 in main ()
(gdb) detach
Detaching from program: /tmp/bracket/build/2020.02.25.00.42.12-amd64-baremetal/tools/bin/nbctfmerge, process 20724
[Inferior 1 (process 20724) detached]
(gdb) quit

>How-To-Repeat:

Don't know, it has only happened once so far.

>Fix: