diff --git a/Makefile.am b/Makefile.am
index 20540cb660..f7553682a8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -222,8 +222,8 @@ endif
 
 bin_SCRIPTS = scripts/gentls_cert scripts/fsxs
 
-src/include/switch_swigable_cpp.h: src/include/switch_cpp.h
-	$(CC) -E src/include/switch_cpp.h -DSWITCH_DECLARE_CLASS= -DSWITCH_DECLARE\(x\)=x -DSWITCH_DECLARE_CONSTRUCTOR= -DSWITCH_DECLARE_NONSTD\(x\)=x 2>/dev/null | grep -v "^#" > src/include/switch_swigable_cpp.h 
+src/include/switch_swigable_cpp.h: $(switch_srcdir)/src/include/switch_cpp.h
+	$(CC) -E $(switch_srcdir)/src/include/switch_cpp.h -DSWITCH_DECLARE_CLASS= -DSWITCH_DECLARE\(x\)=x -DSWITCH_DECLARE_CONSTRUCTOR= -DSWITCH_DECLARE_NONSTD\(x\)=x 2>/dev/null | grep -v "^#" > src/include/switch_swigable_cpp.h 
 
 libs/libedit/src/.libs/libedit.a:
 	cd libs/libedit && $(MAKE)