Ensure that the Makefile variable expansion

in distutils.sysconfig matches that in the
toplevel sysconfig module.

Without this patch universal builds on OSX are
broken.

Als add a test that checks that the two version
of get_config_vars agree on important values.

1 files changed, 23 insertions, 0 deletions

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 0fbd5412bc..48f3fe4d59 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -300,6 +300,12 @@ def parse_makefile(fn, g=None):
                 else:
                     done[n] = v
 
+    # Variables with a 'PY_' prefix in the makefile. These need to
+    # be made available without that prefix through sysconfig.
+    # Special care is needed to ensure that variable expansion works, even
+    # if the expansion uses the name without a prefix.
+    renamed_variables = ('CFLAGS', 'LDFLAGS', 'CPPFLAGS')
+
     # do variable interpolation here
     while notdone:
         for name in list(notdone):
@@ -316,6 +322,16 @@ def parse_makefile(fn, g=None):
                 elif n in os.environ:
                     # do it like make: fall back to environment
                     item = os.environ[n]
+
+                elif n in renamed_variables:
+                    if name.startswith('PY_') and name[3:] in renamed_variables:
+                        item = ""
+
+                    elif 'PY_' + n in notdone:
+                        found = False
+
+                    else:
+                        item = str(done['PY_' + n])
                 else:
                     done[n] = item = ""
                 if found:
@@ -330,6 +346,13 @@ def parse_makefile(fn, g=None):
                         else:
                             done[name] = value
                         del notdone[name]
+
+                        if name.startswith('PY_') \
+                            and name[3:] in renamed_variables:
+
+                            name = name[3:]
+                            if name not in done:
+                                done[name] = value
             else:
                 # bogus variable reference; just drop it since we can't deal
                 del notdone[name]