diff --git a/lib/Makefile.am b/lib/Makefile.am
index c1ec14e82f9bb676300f7cb72de480e8701c7992..8f0113eda97cc6f392e212a929cb3c31f3e779b7 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -54,11 +54,15 @@ LIBCURL_LIBS = @LIBCURL_LIBS@
 # $(top_srcdir)/include is for libcurl's external include files
 # $(top_builddir)/lib is for libcurl's generated lib/config.h file
 # $(top_srcdir)/lib is for libcurl's lib/setup.h and other "private" files
+# $(top_builddir)/ares is for in-tree c-ares's generated ares_build.h file
+# $(top_srcdir)/ares is for in-tree c-ares's external include files
 
 INCLUDES = -I$(top_builddir)/include \
            -I$(top_srcdir)/include   \
            -I$(top_builddir)/lib     \
-           -I$(top_srcdir)/lib
+           -I$(top_srcdir)/lib       \
+           -I$(top_builddir)/ares    \
+           -I$(top_srcdir)/ares
 
 if SONAME_BUMP
 #