build: Include <config.h> through -include for all source files
diff --git a/src/Makefile.am b/src/Makefile.am
index 153c7b8..0bfeb07 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -6,6 +6,7 @@ CFLAGS = -Wall -Wextra -Wno-unused-variable -Wno-unused-parameter
AM_CPPFLAGS = \
-I$(top_builddir) \
-isystem $(top_srcdir)/include/bsd/ \
+ -include $(top_builddir)/config.h \
-DLIBBSD_OVERLAY -DLIBBSD_DISABLE_DEPRECATED \
-D_GNU_SOURCE -D__REENTRANT