I wrote:
> BTW, it sure looks like the part of ACX_PTHREAD beginning with
> # Various other checks:
> if test "x$acx_pthread_ok" = xyes; then
> (lines 163..210 in HEAD's acx_pthread.m4) is dead code.
On closer inspection, this has been broken since commit
e48322a6d6cfce1ec52ab303441df329ddbc04d1, which is just barely short of
its tenth birthday. The reason we've not noticed is that Postgres makes
no use of PTHREAD_CREATE_JOINABLE, nor of PTHREAD_CC, nor of HAVE_PTHREAD,
nor of the success/failure options for ACX_PTHREAD.
I'm tempted to just rip out all the useless code rather than fix the
logic bug as such. OTOH, that might complicate updating to more recent
versions of the original Autoconf macro. On the third hand, we've not
bothered to do that in ten years either.
Thoughts?
regards, tom lane