At module cleanup time, clear the module dict before the global references that its content might still be using.

Keep owned references to builtins module, "cython_runtime" module and preimport module to prevent crashes when they get removed from sys.modules. Generate cleanup code for them in the end.
Closes #2885.

Closes GH-2884.

Issue a warning when casting a GIL-requiring function into a nogil function (which breaks GIL validation).
Closes GH-2879.

See #2879.

Refactor parsing function in code coverage plugin to split the actual parsing code from the lookup code.

Exclude non-executable lines from coverage analysis (anything that does not generate a line trace call).

GH-1461: Include the signature line of cdef functions in the import-time line tracing and coverage report.

GH-1461: Include the signature line of cdef functions in the import-time line tracing and coverage report.

This reverts commit d49062fd.

When detecting an invalid system configuration for overflow checks, at least print a warning, instead of leaving a dangling live exception behind.

This fixes Github issue #2819.

Closes #1470.

Closes GH-2845.

GCC diagnostic pragmas were introduced in GCC 4.6, so augment the GCC
compiler check with a version check to avoid compilation errors with GCC
< 4.6.

Add safety cast in queue tutorial code that avoids casting a potentially non-pointer-sized "int" to a "void*".

Silence an "unused" C compiler warning when we cannot easily decide whether to include the "__Pyx_Method_ClassMethod" utility code or not.

Add safety parentheses in helper macro, also to avoid a compiler warning about tautological comparisons.

Make the cpdef override check work with Python subclasses of extension types again that do not initialise their own dict.
This lead to a crash with dict versioning in Py3.6+.
Closes GH-2823.

Do not install test dependencies on CPython dev versions in travis as they are likely to fail in pre-releases.