Junio C Hamano [off-list ref] writes:

...
So, let's give Pranit a concrete "here is what we want to see
squashed in", while you guys discuss peculiarity with various
platforms and their system headers, which admittedly is a more
interesting tangent ;-)

There are early returns with "goto finish" even before _syn
variables are first assigned to, so they would need to be
initialized to NULL.  The other two get their initial values
right at the beginning, so they are OK.

 builtin/bisect--helper.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

While we are waiting for the topic to be fixed, I've tentatively
applied this on top to update 'pu', so Travis should now be happy
with 'pu' on Mac, too.