Remove mention of HAVE_CONFIG_H
diff --git a/Doc/ext.tex b/Doc/ext.tex
index 6603eb0..f133a3f 100644
--- a/Doc/ext.tex
+++ b/Doc/ext.tex
@@ -1286,9 +1286,7 @@
 the toplevel Python directory, your \var{CFLAGS} Make variable should
 contain the options \samp{-I\$(PYTHONTOP) -I\$(PYTHONTOP)/Include}.
 (Most header files are in the \file{Include} subdirectory, but the
-\file{config.h} header lives in the toplevel directory.)  You must
-also add \samp{-DHAVE_CONFIG_H} to the definition of \var{CFLAGS} to
-direct the Python headers to include \file{config.h}.
+\file{config.h} header lives in the toplevel directory.)
 
 
 \subsection{Shared Libraries}