I was kicking off a build on a cloud instance for the final series of my
SHA-256 work and I noticed that t4068 fails with -fsanitize=address
using Debian's GCC 9.3.0-14 (the version in unstable).  It has failed
since the test was introduced and currently fails on the latest HEAD.

I haven't had time to look at it, but I thought I'd pass the information
on so we can get it fixed before the release.  I'll take a look if
nobody else gets to it first, but it may be a few days.

Reproduction steps:

  printf 'DEVELOPER=1\nDC_SHA1=1\nBLK_SHA256=1\nSANITIZE=address\n' >config.mak
  make -j6 all && (cd t && ./t4068-*.sh --verbose)

Output with --verbose:

expecting success of 4068.4 'diff with no merge bases':
        test_must_fail git diff br2...br3 >tmp 2>err &&
        test_i18ngrep "fatal: br2...br3: no merge base" err

test_must_fail: died by signal 6: git diff br2...br3
not ok 4 - diff with no merge bases
#
#               test_must_fail git diff br2...br3 >tmp 2>err &&
#               test_i18ngrep "fatal: br2...br3: no merge base" err
#
-- 
brian m. carlson: Houston, Texas, US