Issue #20211: Merge 3.6.

Misc/NEWS

@@ -540,6 +540,10 @@ Documentation
 Build
 -----
 
+- Issue #20211: Do not add the directory for installing C header files and the
+  directory for installing object code libraries to the cross compilation
+  search paths. Original patch by Thomas Petazzoni.
+
 - Issue #28849: Do not define sys.implementation._multiarch on Android.
 
 - Issue #10656: Fix out-of-tree building on AIX.  Patch by Tristan Carel and

setup.py

@@ -533,8 +533,9 @@ def detect_modules(self):
                     for directory in reversed(options.dirs):
                         add_dir_to_list(dir_list, directory)
 
-        if os.path.normpath(sys.base_prefix) != '/usr' \
-                and not sysconfig.get_config_var('PYTHONFRAMEWORK'):
+        if (not cross_compiling and
+                os.path.normpath(sys.base_prefix) != '/usr' and
+                not sysconfig.get_config_var('PYTHONFRAMEWORK')):
             # OSX note: Don't add LIBDIR and INCLUDEDIR to building a framework
             # (PYTHONFRAMEWORK is set) to avoid # linking problems when
             # building a framework with different architectures than