Issue #15819: Merge include search from 3.5 into 3.6
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index 214422d..ec0ace8 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -3875,17 +3875,17 @@
       Test whether the set is a proper superset of *other*, that is, ``set >=
       other and set != other``.
 
-   .. method:: union(other, ...)
+   .. method:: union(*others)
                set | other | ...
 
       Return a new set with elements from the set and all others.
 
-   .. method:: intersection(other, ...)
+   .. method:: intersection(*others)
                set & other & ...
 
       Return a new set with elements common to the set and all others.
 
-   .. method:: difference(other, ...)
+   .. method:: difference(*others)
                set - other - ...
 
       Return a new set with elements in the set that are not in the others.
@@ -3935,17 +3935,17 @@
    The following table lists operations available for :class:`set` that do not
    apply to immutable instances of :class:`frozenset`:
 
-   .. method:: update(other, ...)
+   .. method:: update(*others)
                set |= other | ...
 
       Update the set, adding elements from all others.
 
-   .. method:: intersection_update(other, ...)
+   .. method:: intersection_update(*others)
                set &= other & ...
 
       Update the set, keeping only elements found in it and all others.
 
-   .. method:: difference_update(other, ...)
+   .. method:: difference_update(*others)
                set -= other | ...
 
       Update the set, removing elements found in others.
diff --git a/Makefile.pre.in b/Makefile.pre.in
index cffb1a1..3ddeedf 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -94,7 +94,7 @@
 # Both CPPFLAGS and LDFLAGS need to contain the shell's value for setup.py to
 # be able to build extension modules using the directories specified in the
 # environment variables
-PY_CPPFLAGS=	$(BASECPPFLAGS) -I. -IInclude -I$(srcdir)/Include $(CONFIGURE_CPPFLAGS) $(CPPFLAGS)
+PY_CPPFLAGS=	$(BASECPPFLAGS) -I. -I$(srcdir)/Include $(CONFIGURE_CPPFLAGS) $(CPPFLAGS)
 PY_LDFLAGS=	$(CONFIGURE_LDFLAGS) $(LDFLAGS)
 NO_AS_NEEDED=	@NO_AS_NEEDED@
 LDLAST=		@LDLAST@
diff --git a/Misc/NEWS b/Misc/NEWS
index 5f2ded4..34c3748 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -13,6 +13,12 @@
 Library
 -------
 
+Build
+-----
+
+- Issue #15819: Remove redundant include search directory option for building
+  outside the source tree.
+
 
 What's New in Python 3.6.0 beta 1
 =================================