Enforcing library version in a port Makefile?

[Alex Stangl]

Hi,

I am trying to create a new port. The software I am trying to port uses
scons which calls out to pkg-config to check for certain minimal library
version #s (e.g., sndfile >= 1.0.18, libcurl >= 7).

I would like to enforce these same checks upfront in the Makefile rather
than letting the build potentially blow up in scons. Section 5.7.8 of the
Porter's Handbook says that all of the _DEPENDS variables *except
LIB_DEPENDS* can enforce minimal dependency versions. It's not clear why
LIB_DEPENDS is excluded here, or what the correct alternative approach
is. It doesn't seem like putting LIB_DEPENDS= curl.5 is equivalent to
libcurl >= 7. Hopefully there's a straightforward way to accomplish
this, without having to patch or scrap the scons config file.
Unfortunately I have not been able to find the answers from
searching the net, so I hope somebody here can help.

Thanks,

Alex