diff --git a/lib/Makefile.am b/lib/Makefile.am
index 3086cf0..97bf732 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -39,8 +39,8 @@
 
 noinst_HEADERS = fixedsizehash.h libeu.h system.h dynamicsizehash.h list.h \
 		 eu-config.h color.h printversion.h bpf.h \
-		 atomics.h stdatomic-fbsd.h
-EXTRA_DIST = dynamicsizehash.c
+		 atomics.h stdatomic-fbsd.h dynamicsizehash_concurrent.h
+EXTRA_DIST = dynamicsizehash.c dynamicsizehash_concurrent.c
 
 if !GPROF
 xmalloc_CFLAGS = -ffunction-sections