AIX7.2: test-fcntl fails when run via AIX make with -j

[Bernhard Voelker]

I notice that 'test-fcntl' fails on AIX7.2 when run from AIX make with any -j 
value,
but succeeds if run both without -j or when run via gmake.
Reproducer:

Export 'fcntl' module into a tarball, and transfer it to the AIX7.2 host.

  $ ./gnulib-tool --create-testdir --dir=/tmp/gl-fcntl --single-configure fcntl 
\
      && cd /tmp \
      && tar -zcf gl-fcntl.tar.gz gl-fcntl \
      && scp -p gl-fcntl.tar.gz gcc119.fsffrance.org:

Logon there.

  $ ssh gcc119.fsffrance.org

Go away from ksh.

  $ exec bash --login

Build the 'fcntl' module.

  $ gzip -d -c - < gl-fcntl.tar.gz \
      | tar -xf - \
      && cd gl-fcntl \
      && ./configure && make

Run tests with -j4 --> test-fcntl fails:

  $ make -j4 check
  ...
  FAIL: test-fcntl
  ...

  $ cat gltests/test-fcntl.log
  FAIL test-fcntl (exit status: 42)

Run tests without -j --> test-fcntl succeeds:

  make check
  ...
  PASS: test-fcntl
  ...

Funny thing is: it fails even with -j1:

  $ make -j1 check
  ...
  FAIL: test-fcntl
  ...

Finally: no problems with gmake:

  $ gmake -j4 check
  ...
  PASS: test-fcntl
  ...

Is this worth investigating/fixing?

Have a nice day,
Berny