--- doc/Makefile.in.orig	2017-07-09 21:49:56.000000000 -0700
+++ doc/Makefile.in	2017-07-09 21:50:12.000000000 -0700
@@ -511,7 +511,7 @@
 noinst_DATA = $(figures) $(rst_files) $(static_files)
 EXTRA_DIST = $(man_MANS) $(noinst_DATA) gsl-design.texi gsl-ref.info conf.py
 SPHINX_OPTS = 
-SPHINX_BUILD = sphinx-build
+SPHINX_BUILD = __MACPORTS_SPHINX_BUILD__
 SPHINX_SOURCEDIR = .
 SPHINX_BUILDDIR = _build