| Python uses a hand-rolled Makefile parser to pick out important build-related |
| environment variables and stash them in the `sysconfig` module. Crucially, it'll |
| take a Makefile that looks like |
| |
| ``` |
| FOO = 1 |
| BAR = $(FOO) $(BAZ) $(QUX) |
| ``` |
| |
| ...And given an environment of {'FOO': 99, 'BAZ': '98'}, will produce something |
| like {'FOO': '1', 'BAR': '1 98 '} |
| |
| Since EXTRA_CFLAGS is literally only used as a means to pass a PGO profile in, |
| and that profile won't be available to anything but the core Python modules, we |
| clear EXTRA_CFLAGS for the generation of sysconfig. |
| |
| --- a/Makefile.pre.in |
| +++ b/Makefile.pre.in |
| @@ -456,6 +456,7 @@ platform: $(BUILDPYTHON) pybuilddir.txt |
| # or removed in case of failure. |
| pybuilddir.txt: $(BUILDPYTHON) |
| @echo "none" > ./pybuilddir.txt |
| + EXTRA_CFLAGS= \ |
| $(RUNSHARED) $(PYTHON_FOR_BUILD) -S -m sysconfig --generate-posix-vars ;\ |
| if test $$? -ne 0 ; then \ |
| echo "generate-posix-vars failed" ; \ |
