This time hopefully should work reliably, using make $(wildcard) function,
which in this case either expands to existing prj_$(BOARD).conf file, or to
an empty string for non-existing one.

Zephyr 1.10 switches to CMake-based build system (already in master).

As useful for CI systems. 1.10 doesn't build .bin for qemu_* for example.

Also, remove deprecated CONFIG_LEGACY_KERNEL option.

Fails for Zephyr qemu_x86 with:

-9e-36
+9.000001e-36

It has equivalent behaviour and reusing it saves some code bytes.

This patch improves parsing of floating point numbers by converting all the
digits (integer and fractional) together into a number 1 or greater, and
then applying the correct power of 10 at the very end.  In particular the
multiple "multiply by 0.1" operations to build a fraction are now combined
together and applied at the same time as the exponent, at the very end.

This helps to retain precision during parsing of floats, and also includes
a check that the number doesn't overflow during the parsing.  One benefit
is that a float will have the same value no matter where the decimal point
is located, eg 1.23 == 123e-2.

Per POSIX, http://pubs.opengroup.org/onlinepubs/9699919799/functions/poll.html
these flags aren't valid in the input eventmask. Instead, they can be
returned in unsolicited manner in the output eventmask at any time.

Put offset first in OR expressions, and use "offset" var instead of
hardcoded numbers. Hopefully, this will make it more self-describing
and show patterns better.

Dramatically improves TCP sending throughput because without an explicit
call to tcp_output() the data is only sent to the lower layers via the
lwIP slow timer which (by default) ticks every 500ms.

The key and cert must both be a str/bytes object in DER format.

Before this patch MP_BINARY_OP_IN had two meanings: coming from bytecode it
meant that the args needed to be swapped, but coming from within the
runtime meant that the args were already in the correct order.  This lead
to some confusion in the code and comments stating how args were reversed.
It also lead to 2 bugs: 1) containment for a subclass of a native type
didn't work; 2) the expression "{True} in True" would illegally succeed and
return True.  In both of these cases it was because the args to
MP_BINARY_OP_IN ended up being reversed twice.

To fix these things this patch introduces MP_BINARY_OP_CONTAINS which
corresponds exactly to the __contains__ special method, and this is the
operator that built-in types should implement.  MP_BINARY_OP_IN is now only
emitted by the compiler and is converted to MP_BINARY_OP_CONTAINS by
swapping the arguments.

By directly including runtime0.h the mpconfig.h settings are not included
and so the enums in runtime0.h can be incorrect.

In mp_binary_op, there is no need to explicitly check for type->getiter
being non-null and raising an exception because this is handled exactly by
mp_getiter().  So just call the latter unconditionally.

This generalises and simplifies the code and follows CPython behaviour.

By declaring interface in objnamedtuple.h and introducing a helper
allocation function.

This patch introduces a new compile-time config option to disable multiple
inheritance at the Python level: MICROPY_MULTIPLE_INHERITANCE.  It is
enabled by default.

Disabling multiple inheritance eliminates a lot of recursion in the call
graph (which is important for some embedded systems), and can be used to
reduce code size for ports that are really constrained (by around 200 bytes
for Thumb2 archs).

With multiple inheritance disabled all tests in the test-suite pass except
those that explicitly test for multiple inheritance.

These board-level macros have been completely replaced by feature-level
config options.

This is a low-cost evaluation kit board from ST based on the STM32
Nucleo-144 form factor.  It uses the STM32F746ZG MCU in the LQFP144
package.  The MCU has 1MB of flash and 320kB of System RAM.
Cortex-M7 runs at up to 216MHz.

It's possible to use the methods (eg ilistdir) of a VFS FatFS object
without it being mounted in the VFS itself.  This previously worked but
only because FatFS was "mounting" the filesystem automatically when any
function (eg f_opendir) was called.  But it didn't work for ports that used
synchronisation objects (_FS_REENTRANT) because they are only initialised
via a call to f_mount.  So, call f_mount explicitly when creating a new
FatFS object so that everything is set up correctly.  Then also provide a
finaliser to do the f_umount call, but only if synchronisation objects are
enabled (since otherwise the f_umount call does nothing).

The argument is optional and if given should be a string naming the
status variable to query.

This patch uses existing qstr data where possible when constructing a str
from a bytes object.

The function mp_obj_new_str_of_type is a general str object constructor
used in many places in the code to create either a str or bytes object.
When creating a str it should first check if the string data already exists
as an interned qstr, and if so then return the qstr object.  This patch
makes the function have such behaviour, which helps to reduce heap usage by
reusing existing interned data where possible.

The old behaviour of mp_obj_new_str_of_type (which didn't check for
existing interned data) is made available through the function
mp_obj_new_str_copy, but should only be used in very special cases.

One consequence of this patch is that the following expression is now True:

    'abc' is ' abc '.split()[0]

This patch simplifies the str creation API to favour the common case of
creating a str object that is not forced to be interned.  To force
interning of a new str the new mp_obj_new_str_via_qstr function is added,
and should only be used if warranted.

Apart from simplifying the mp_obj_new_str function (and making it have the
same signature as mp_obj_new_bytes), this patch also reduces code size by a
bit (-16 bytes for bare-arm and roughly -40 bytes on the bare-metal archs).