The compiler flag has been added to CFLAGS_NODIST and
LDFLAGS_NODIST. This will compile the core interpreter
and the stdlib modules with -fno-semantic-interposition
but will not affect user build and rpm C extension modules
compiled by distutils.
This has the effect of speeding up the interpreter up to
27%, depending on the workload, with the drawback of disabling
the capability of using LD_PRELOAD to override symbols in
libpython.
https://fedoraproject.org/wiki/Changes/PythonNoSemanticInterpositionSpeedup
The tkinter module is part of the Python's standard library, however it is in
a separate subpackage to save an unwanted dependency on tk.
When tk is installed, we recommend the subpackage to provide more upstream-like
experience, but still provide a way out.
The bcond flatpackage assumed that if building *without* flatpackage,
that we want to build the main Python for the distribution. However, in
some instances we want a non-flatpackage build of Python that is *not*
the main Python in the distro.
Therefore I have split the main-Python setting into its own bcond.
