gzip just took my patch to initialise MAINTAINERCLEANFILES, just built from HEAD with gnulib pulled from HEAD, everything looking good
make check
============================================================================
Testsuite summary for gzip 1.13.36-46e9-dirty
============================================================================
# TOTAL: 29
# PASS: 29
# SKIP: 0
# XFAIL: 0
# FAIL: 0
# XPASS: 0
# ERROR: 0
============================================================================
$ time ./gzip_old -c -d -k large_file.gz > /dev/null
real 0m0.502s
user 0m0.473s
sys 0m0.030s
$ time ./gzip_new -c -d -k large_file.gz > /dev/null
real 0m0.318s
user 0m0.303s
sys 0m0.010s
gzip just needs to update the submodule now? that's another PATCH for them?