This one meets or exceeds the following requirements:

 - Version is checked/updated for every build action when in the git repo.
   Does not require the user to re- ./configure to get the correct version.

 - Version is not updated automatically when using exported tarball source.
   Avoids accidentally getting a wrong version from some other git repo in
   a parent directory of the source, and allows setting the correct version
   for distro package exports.

 - Automatic updating can be manually suppressed.
   For developers doing lots of change/rebuild cycles they don't plan to
   release, when they don't want a full rebuild triggered for every commit,
   and again for every change made immediately after a commit.
   The version will still always be updated if they do a `make dist`.

 - Does not require any manual updating of versions in the mainline git
   repo for each release aside from normal tagging.  The version is
   recorded in one file only, that is automatically generated and will
   never need to be committed.

 - Does not require gnu-make features for the autoconf builds.

It does not currently:

 - Keep a checksum of every source file in tarball releases to mangle the
   version if people modify the tarball source.  Responsible people can
   manually update the version easily though in such cases.

Ulrich Klauer authored 11 years ago and Timothy B. Terriberry committed 11 years ago

Libraries that are used internally by opusfile but are not part of
 its API should be listed in pkg-config "private" clauses.
Otherwise executables that are linked dynamically against opusfile
 will have unneeded direct dependencies (overlinking).

Signed-off-by: Timothy B. Terriberry <tterribe@xiph.org>

Ulrich Klauer authored 11 years ago and Timothy B. Terriberry committed 11 years ago

The library does not actually do any playback, as it does no sound
 output.

Signed-off-by: Timothy B. Terriberry <tterribe@xiph.org>

Ulrich Klauer authored 12 years ago and Timothy B. Terriberry committed 11 years ago

AC_SEARCH_LIBS will give a result of "none required" if the relevant
 function is available without any special libraries.
This is the case for lrintf on MinGW.
Make sure this special value isn't put verbatim into the pkg-config
 files, as it would cause the linker to search for files named
 "none" and "required", and fail.

Signed-off-by: Timothy B. Terriberry <tterribe@xiph.org>

Also use Libs.private for libm.