diff --git a/src/bin/Makefile.am b/src/bin/Makefile.am
index 3bbb8c1..9bd81a8 100644
--- a/src/bin/Makefile.am
+++ b/src/bin/Makefile.am
@@ -3,7 +3,7 @@ MAINTAINERCLEANFILES = Makefile.in
 AM_CFLAGS   = $(CFLAGS_WARNINGS) $(CFLAGS_ASAN)
 AM_CPPFLAGS = \
 -DPACKAGE_DATA_DIR=\"$(datadir)/$(PACKAGE)\" \
--I$(top_srcdir)/src/lib \
+-I$(top_builddir)/src/lib \
 $(X_CFLAGS)
 
 if BUILD_X11
diff --git a/test/Makefile.am b/test/Makefile.am
index b46bf99..779faf1 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -16,6 +16,7 @@ CLEANFILES = file.c img_save-*.*
  AM_CXXFLAGS = $(AM_CFLAGS)
 
  AM_CPPFLAGS  = -I $(top_builddir) -I $(top_srcdir)/src/lib
+ AM_CPPFLAGS += -I $(top_builddir)/src/lib
  AM_CPPFLAGS += -D SRC_DIR='"$(top_srcdir)"'
  AM_CPPFLAGS += -D BUILD_TEST=1