[cairo] make check failed while all tests passed

[darxus at chaosreigns.com]

make check failed:

make  check-TESTS
make[5]: Entering directory '/home/darxus/source/cairo/test'
make[6]: Entering directory '/home/darxus/source/cairo/test'
FAIL: cairo-test-suite
============================================================================
Testsuite summary for cairo 1.15.2
============================================================================
# TOTAL: 1
# PASS:  0
# SKIP:  0
# XFAIL: 0
# FAIL:  1
# XPASS: 0
# ERROR: 0
============================================================================
See test/test-suite.log
Please report to http://bugs.freedesktop.org/enter_bug.cgi?product=cairo
============================================================================
Makefile:8392: recipe for target 'test-suite.log' failed
make[6]: *** [test-suite.log] Error 1


But all the tests passed:

cairo/test/output$ cat *.log | grep ^TEST: | cut -d' ' -f14  | sort | uniq -c | sort -nr
   5321 PASS
     10 XFAIL
      9 UNTESTED


I'm doing automated build tests, which have run this lots of times.
Usually passes.  Currently running with targets xcb,image,image16.