Typo in Makefile.am, AM_CPPFLAGS should append to the previous value.
@@ -67,7 +67,7 @@ AM_CPPFLAGS += -DENABLE_IMFHUGETEST
endif
-AM_CPPFLAGS = -I$(top_builddir) \
+AM_CPPFLAGS += -I$(top_builddir) \
-I$(top_srcdir)/IlmImf \
-I$(top_srcdir)/config \
@ILMBASE_CXXFLAGS@ $(ILMBASE_CFLAGS) $(ZLIB_CFLAGS)
