awk's equality-comparison operator is "==" not "=". We got this right
in many places, but not in configure's checks for supported version
numbers of flex and perl. It hadn't been noticed because unsupported
versions are so old as to be basically extinct in the wild, and because
the only consequence is whether or not a WARNING flies by during
configure.
Daniel Gustafsson noted the problem with respect to the test for flex,
I found the other by reviewing other awk calls.
This means we can now construct a configure test for the library
presence. Previously these parameters were only figured out at
build time in plperl's GnuMakefile.
versions < 5.8. Also, if there's no Perl, emit a warning informing the
user that he won't be able to build from a CVS pull. This is exactly the
same treatment we give Bison and Perl, and for the same reasons.
perl_embed_ldflags setting. On OS X it seems that ExtUtils::Embed is
trying to force a universal binary to be built, but you need to specify
that a lot further upstream if you want Postgres built that way; the only
result of including -arch in perl_embed_ldflags is some warnings at the
plperl.so link step. Per my complaint and Jan Otto's suggestion.
