By disabling "CYTHON_FAST_THREAD_STATE" and "CYTHON_USE_EXC_INFO_STACK"

I think this still leaves some breakage in Coroutines.c but it's enough of a fix that Cython succeeds in building itself. Therefore I think it's worth doing now even if it doesn't fix everything.

Related to https://github.com/cython/cython/issues/4500

Fix division-by-zero crash in tests when the C ompiler discards the computational body of a Cython coroutine.

Add a new command line option so that
$ cythonize -M foo.pyx
produces a file `foo.c.dep` with the dependencies of foo.pyx, in addition to `foo.c`.
Try to write relative paths as much as possible.

Backport of https://github.com/cython/cython/pull/4563

Make the test files that depend on "cythonarrayutil.pxi" compilable by themselves, without the search directory setup of the test runner.

Use "Py_ssize_t" instead of "int" for a node counter variable to avoid uselessly limiting its value range.

Disable parallel builds in the 0.29.x branch since they currently misbehave and fail in CI, trying to rebuild everything multiple times in parallel.

Cython incorrectly generated (optimised) range code for "for i in range(1,2,3,4)" as if it saw "for i in range(1,2,3)".
This PR deactivates this optimization when too many arguments are provided, to match the behavior of Python.
Original patch by Max Bachmann.

Closes https://github.com/cython/cython/pull/4550

Remove outdated warning about OpenMP < 3.0. Even the now-EOL Docker images for manylinux2010 had that.

Closes https://github.com/cython/cython/issues/4574

For PyPy3.8 (the current release is 7.3.7)

* PyPy<7.3.8 declares a struct with the last fields tp_finalize, tp_print, tp_pypy_flags
* PyPy>=7.3.8 will declare a struct with the last fields tp_finalize, tp_vectorcall, tp_print

PyPy3.9 (not yet released) will declare a struct with the last fields tp_finalize, tp_vectorcall, tp_pypy_flags

See https://foss.heptapod.net/pypy/pypy/-/issues/3618

Add "tp_pypy_flags" field to PyTypeObject struct when compiling in PyPy 6.0+ in order to avoid C compiler warnings about an uninitialised struct field.

This reverts commit f5aa00bb.

Closes https://github.com/cython/cython/issues/3938

Fixes an issue which Pyston triggers.
See https://github.com/cython/cython/issues/4200

Exception messages had changed a little

Let a tracing test run slower to prevent div-by-zero crashes in line_profiler due to measured zero runtime.

Python 3.11 hid _PyLong_FormatAdvancedWriter and
_PyFloat_FormatAdvancedWriter. I've disabled USE_UNICODE_WRITER
for the moment but I suspect we want to find replacements in the longer term.

To silence a compiler warning since it was added in Python 3.11a2.

For 0.29.x branch only.

With reference to https://github.com/cython/cython/issues/4365#issuecomment-977023011
in Python 3 PyCode_NewEmpty does everything we need to set
exception traceback code objects.

This change is probably only a real improvement on Py3.11 onwards
(where the replacement for PyCode_new is currently pretty slow).
On earlier version it'll probably be fairly similar (maybe one extra allocation for the cline case?)