Prior to this patch there were 2 paths for creating the namedtuple, one for
when no keyword args were passed, and one when there were keyword args.
And alloca was used in the keyword-arg path to temporarily create the array
of elements for the namedtuple, which would then be copied to a
heap-allocated object (the namedtuple itself).
This patch simplifies the code by combining the no-keyword and keyword
paths, and removing the need for the alloca by constructing the namedtuple
on the heap before populating it.
Heap usage in unchanged, stack usage is reduced, use of alloca is removed,
and code size is not increased and is actually reduced by between 20-30
bytes for most ports.
By default the firmware is built with single-precision floating point.
To build a particular board using double precision instead, put the
following line in the mpconfigboard.mk file:
FLOAT_IMPL = double
The while-loop that calls chop_component will guarantee that level==-1 at
the end of the loop. Hence the code following it is unnecessary.
The check for p==this_name will catch imports that are beyond the
top-level, and also covers the case of new_mod_q==MP_QSTR_ (equivalent to
new_mod_l==0) so that check is removed.
There is also a new check at the start for level>=0 to guard against
__import__ being called with bad level values.