diff --git a/platform/unix/gen-makefile b/platform/unix/gen-makefile
index dc4ab7bf7..1008df63b 100644
--- a/platform/unix/gen-makefile
+++ b/platform/unix/gen-makefile
@@ -1,7 +1,7 @@
 #!/bin/bash
 echo Generating src/Makefile.am ...
 cd src
-inc_current=.
+inc_current='$(srcdir)'
 inc_modules="$inc_current/modules"
 inc_libraries="$inc_current/libraries"
 echo "AM_CPPFLAGS = -I$inc_current -I$inc_modules -I$inc_libraries -I/usr/include/AL -I/usr/include/freetype2  \$(INCLUDE_LUA) -I/usr/include/SDL \$(FILE_OFFSET) -I/usr/include/gme