distutils incorrectly handles CFLAGS as 1 argument instead of
space-separated list of arguments. distutils should respect environment
variables, which set compiler, linker etc.

--- Lib/distutils/unixccompiler.py
+++ Lib/distutils/unixccompiler.py
@@ -297,7 +297,7 @@
        # this time, there's no way to determine this information from
        # the configuration data stored in the Python installation, so
        # we use this hack.
-        compiler = os.path.basename(sysconfig.get_config_var("CC"))
+        compiler = os.path.basename(self.compiler[0])
        if sys.platform[:6] == "darwin":
            # MacOSX's linker doesn't understand the -R flag at all
            return "-L" + dir

Patch was created by Arfrever Frehtes Taifersar Arahesis (arfrever.fta@gmail.com). It was originally written for PyPy, but it seems like it should actually apply to the stdlib. This patch is for 2.7, I'm hoping it could be taken as a bug fix.

Could you explain more about what the bug is?

The bug is specific to PyPy. PyPy has no Makefile, so sysconfig.get_config_var("CC") returns None in PyPy. The first paragraph in message #153471 is about a different patch, not this patch.

> PyPy has no Makefile, so sysconfig.get_config_var("CC") returns None in PyPy.
Do you think the stdlib sysconfig could be changed to make this call return something meaningful, or should the code use another method to find the compiler to use?

(Getting config vars for 'SO' is one of the (surprisingly few) issues I’ve found when trying to run distutils2 tests with PyPy, I’d love to fix it.)