diff --git a/GNUmakefile b/GNUmakefile
index 8f44e7d3..144a662d 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -317,6 +317,14 @@ LIBIMPORTOBJS = $(LIBOBJS:.o=.import.o)
 TESTIMPORTOBJS = $(TESTOBJS:.o=.import.o)
 DLLTESTOBJS = dlltest.dllonly.o
 
+#################################################################
+# Public service announcement
+
+ALIGNED_ACCESS = $(shell cat config.h | $(EGREP) -c "^\#define CRYPTOPP_NO_UNALIGNED_DATA_ACCESS")
+ifeq ($(ALIGNED_ACCESS),0)
+$(info WARNING: CRYPTOPP_NO_UNALIGNED_DATA_ACCESS is not defined in config.h)
+endif
+
 #################################################################
 # Recipes