diff -Naur a/include/Makefile.in b/include/Makefile.in
--- a/include/Makefile.in	2014-11-11 06:31:12.000000000 -0600
+++ b/include/Makefile.in	2016-09-29 13:11:39.172000000 -0500
@@ -314,7 +314,7 @@
 AUTOMAKE_OPTIONS = foreign
 DISTCLEANFILES = ffitarget.h
 EXTRA_DIST = ffi.h.in ffi_common.h
-includesdir = $(libdir)/@PACKAGE_NAME@-@PACKAGE_VERSION@/include
+includesdir = $(includedir)
 nodist_includes_HEADERS = ffi.h ffitarget.h
 all: all-am
 
diff -Naur a/libffi.pc.in b/libffi.pc.in
--- a/libffi.pc.in	2014-11-08 06:47:24.000000000 -0600
+++ b/libffi.pc.in	2016-09-29 13:11:52.508000000 -0500
@@ -2,10 +2,10 @@
 exec_prefix=@exec_prefix@
 libdir=@libdir@
 toolexeclibdir=@toolexeclibdir@
-includedir=${libdir}/@PACKAGE_NAME@-@PACKAGE_VERSION@/include
+includedir=@includedir@
 
 Name: @PACKAGE_NAME@
 Description: Library supporting Foreign Function Interfaces
 Version: @PACKAGE_VERSION@
 Libs: -L${toolexeclibdir} -lffi
-Cflags: -I${includedir}
+Cflags: