Historically we've used the SWPB instruction for TAS() on ARM, but this
is deprecated and not available on ARMv6 and later. Instead, make use
of a GCC builtin if available. We'll still fall back to SWPB if not,
so as not to break existing ports using older GCC versions.
Eventually we might want to try using __sync_lock_test_and_set() on some
other architectures too, but for now that seems to present only risk and
not reward.
Back-patch to all supported versions, since people might want to use any
of them on more recent ARM chips.
Martin Pitt
Suggested solution from Tom Lane. Problem discovered, probably not
for the first time, while testing the mingw-w64 32 bit compiler.
Backpatched to all live branches.
The version of this macro used in autoconf 2.59 is capable of incorrectly
succeeding (ie, reporting that a library function is available when it
isn't), if the compiler performs link-time optimization and decides that
it can optimize the function reference away entirely. Replace it with the
coding used in autoconf 2.61 and later, which forces the program result to
depend on the function's result so that it cannot be optimized away. This
should fix build failures currently being seen on buildfarm member anchovy.
This patch affects the 8.2 and 8.3 branches only, since later branches are
using autoconf versions that don't have this problem.
We previously found out that OS X's standard perl installation tries to put
-arch switches into Perl link commands, evidently in hopes of building
universal binaries. But it doesn't work to add such switches in plperl's
link step if they weren't being used earlier, so this is basically
unworkable. When using gcc the result is only some warnings; but LLVM
fails entirely, so this issue isn't as cosmetic as we originally thought.
Hence, back-patch commit d69a419e68 into
pre-9.0 branches.
The mingw people don't appear to care about compatibility with non-GNU
versions of getopt, so force use of our own copy of getopt on Windows.
Also, ensure that we make use of optreset when using our own copy.
Per report from Andrew Dunstan. Back-patch to all versions supported
on Windows.
which is a global variable not a function, and so the probe failed on machines
where the linker makes a distinction (cf. Red Hat bug #444317). Probe for
an actual function instead.
This prevents compiler optimizations that assume overflow won't occur, which
breaks numerous overflow tests that we need to have working. It is known
that gcc 4.3 causes problems and possible that 4.1 does. Per my proposal
of some time ago and a recent report from Kris Jurka.
Backpatch as far as 8.0, which is as far as the patch conveniently goes.
7.x was pretty short of overflow tests anyway, so it may not matter there,
even assuming that anyone cares whether 7.x builds on recent gcc.
itself as libuuid, not libossp-uuid which was the only case expected by
our build support. Install a configure test to determine which name
to use (and to check that the library is present at all).
OpenSSL libraries --- just don't call them if they're not there. This
might possibly lead to misleading error messages, but we'll just have
to live with that.
