* Fix async Python functors invoking from multiple C++ threads (#1587)
Ensure GIL is held during functor destruction.
* Add async Python callbacks test that runs in separate Python thread
In some cases the user of pythonbuf needs to allocate the internal
buffer to a specific size e.g. for performance or to enable synchronous
writes to the buffer.
By changing `pythonbuf::d_buffer` to be dynamically allocated we can now
enable these use-cases while still providing the default behavior of
allocating a 1024 byte internal buffer (through a default parameter).
I found that the numpy array tests already contained an empty-shaped
array test, but none with data in it.
Following PEP 3118, scalars have an empty shape and ndim 0. This
works already and is now also documented/covered by a test.
On some linuxes, /usr/include belongs to GCC and the standard
libraries that work with clang are in /usr/lib/clang/8.0.0 or
some variation thereof.
This results in errors such as:
```
/../lib64/gcc/x86_64-pc-linux-gnu/8.3.0/../../../../include/c++/8.3.0/bits/cxxabi_init_exception.h:38:10: fatal error: 'stddef.h' file not found
```
during extraction.
Bazel has a "strict" build model that requires all C++ header files be compilable on their own, and thus must explicitly #include all headers they require (even if de facto header inclusion order means they'd get them "for free"). This adds a couple of headers that are needed (but missing) by this model.
* Fixing order of arguments in call to PyErr_GivenExceptionMatches in pybind11::error_already_set.matches
* Added tests on error_already_set::matches fix for exception base classes
* Fix warning that not including a cmake source or build dir will be a fatal error (it is now on newest CMakes)
* Fixes appveyor
* Travis uses CMake 3.9 for more than a year now
* Travis dropped sudo: false in December
* Dropping Sphinx 2
- clang7: Suppress self-assign warnings; fix missing virtual dtors
- pypy:
- Keep old version (newer stuff breaks)
- Pin packages to extra index for speed
- travis:
- Make docker explicit; remove docker if not needed
- Make commands more verbose (for debugging / repro)
- Make Ubuntu dist explicit per job
- Fix Windows
- Add names to travis
This avoids GIL deadlocking when pybind11 tries to acquire the GIL in a thread that already acquired it using standard Python API (e.g. when running from a Python thread).
