armv7 targeting via poudriere-devel (armv7 via aarch64): net/dante build ends up with ./conftest stuck in write loop

The aarch64 context is Cortex-A72 based: a 8 GiByte RPi4B.
The build is part of a "bulk -a -c" test that I've
been doing.

top reports the builder activity looks like:

  PID   JID USERNAME    PRI NICE     SIZE       RES STATE    C   TIME     CPU COMMAND
21812    11 root        103    0   4740Ki    1200Ki CPU3     3 113:33  99.93% ./conftest
19726    11 root         52    0   5964Ki    1948Ki wait     0   0:01   0.00% /bin/sh ./configure --with-socks-conf=/usr/local/etc/socks.conf --with-sockd-conf=/usr/local/etc/sockd.conf --prefix=/usr
19327    11 root         52    0   5096Ki    1432Ki wait     1   0:00   0.00% /bin/sh -e -c (cd /wrkdirs/usr/ports/net/dante/work/dante-1.4.3 &&  _LATE_CONFIGURE_ARGS="" ;  if [ -z "" ] &&  ./configu
19217    11 root         52    0   6516Ki    2216Ki wait     0   0:00   0.00% /usr/bin/make -C /usr/ports/net/dante configure

# truss -p 21812 | more
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
write(9,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...,1024) = 1024 (0x400)
. . .

# truss -c -p 21812
^Csyscall                     seconds   calls  errors
write                   2.771261517  206935       0
                      ------------- ------- -------
                        2.771261517  206935       0


(I checked on a separate system and the problem repeated there.)

I'm going to kill process 21812.

===
Mark Millard
marklmi at yahoo.com