The traceback array stores qstrs and line numbers.  qstrs are typed as
size_t, and line numbers should safely fit in size_t as well.

So that if MICROPY_FORCE_32BIT is set mpconfigport.mk it influences
mkenv.mk.

Function to actually spool output terminal data to dupterm object.

To comply with already established scheme for extmod's.

That's just function which sets/gets dup terminal object, and can be
easily reused across ports.

To allow simple zero-terminated lexers.

This makes the code portable to non-32-bit architectures.

The USB REPL has been broken since commit 1be0fde4
This patch allows the STM32F429DISC board (which uses the USB_HS PHY)

It's possible to have a fixed map that is properly hashed (ie not
simply ordered).

Any fields changed by asynchronous callbacks must be volatile.

Polling once in 100ms means dismal performance.

TODO: Propagate this pattern to other polling places.

Otherwise build fails if uctypes is disabled.

Previously, mark operation weren't logged at all, while it's quite useful
to see cascade of marks in case of over-marking (and in other cases too).
Previously, sweep was logged for each block of object in memory, but that
doesn't make much sense and just lead to longer output, harder to parse
by a human. Instead, log sweep only once per object. This is similar to
other memory manager operations, e.g. an object is allocated, then freed.
Or object is allocated, then marked, otherwise swept (one log entry per
operation, with the same memory address in each case).

The default bahaviour for debug builds is to show dialog boxes for asserts
and invalid parameter handling. This is not so nice in general and causes
the Appveyor debug builds to hang because the io\file_seek.py test passes
a closed file descriptor to lseek. Disable this behaviour by printing
assert messages to the output instead of showing the dialog, and by
disabling 'invalid' parameter handling which causes the affected functions
to just return an error and set errno appropriately.

Map indicies are most commonly a qstr, and adding a fast-path for hashing
of a qstr increases overall performance of the runtime.

On pyboard there is a 4% improvement in the pystone benchmark for a cost
of 20 bytes of code size.  It's about a 2% improvement on unix.

When looking up and extracting an attribute of an instance, some
attributes must bind self as the first argument to make a working method
call.  Previously to this patch, any attribute that was callable had self
bound as the first argument.  But Python specs require the check to be
more restrictive, and only functions, closures and generators should have
self bound as the first argument

Addresses issue #1675.

This is a convenience function similar to pyexec_file.  It should be used
instead of raw mp_parse_compile_execute because the latter does not catch
and report exceptions.

This is extension to CPython, it allows to easily produce human-readable
hex dump:

>>> ubinascii.hexlify(b"\xaa\x55\xaa\x55", b" ")
b'aa 55 aa 55'

Addresses issue #1636.

POSIX doesn't guarantee something like that to work, but it works on any
system with careful signal implementation. Roughly, the requirement is
that signal handler is executed in the context of the process, its main
thread, etc. This is true for Linux. Also tested to work without issues
on MacOSX.