I don't know if this is the right solution, but it does fix an issue accessing std::ios::openmode caused by the ios typedef being defined before ios_base is fully specified.
Rationale:
1. Per standard, fstream::open takes 2 arguments.
If platforms add a third, they're out of spec.
2. The only platform I could find that takes a file
mask specifically as the third argument is IRIX,
which Panda hasn't targeted in forever.
3. The mask being requested isn't even particularly
interesting - falling back to a platform default
is best.
4. When USE_PANDAFILESTREAM is defined, pfstream
is implemented as PandaFileStream, which doesn't
have a three-argument open() and breaks immediately.
5. makepanda doesn't ever define HAVE_OPEN_MASK
6. It's been broken for so long that, if it were
important to anybody, it would have been fixed by now.
There is a bug in clang versions before 3.2 (including the one shipped with Xcode) that makes it give a "conflicting types" compile error when there is a static constexpr function defined outside the class. The way to work around this is either to remove one of the "static" or "constexpr" keywords, or to simply put the definition inline.
See: https://stackoverflow.com/a/17494592/2135754
I would try and upgrade Xcode to version 5 to see if the problem is fixed, but the buildbot still runs OS X Lion (10.7) and the last version of Xcode that works on Lion is 4.6.3, so it seems easier to just apply these workarounds for now.
This renames acquire/release to lock/unlock in order to be compatible with std::lock_guard and std::unique_lock (which will eventually replace the *MutexHolder classes). It will also allow us to typedef MutexImpl to std::mutex later on.
A blank string to FindPythonInterp finds the version
of Python that the system "python" interpreter invokes,
so this means the default is now the system default.
This removes the requirement that it only be included
in a single C++ file per library, by forcing the compiler
to emit the function that references the version symbol
as a weak symbol itself. Now, the linker will not only
tolerate redundant inclusions, it will also coalesce them
together.