diff --git a/app/crypto/Makefile b/app/crypto/Makefile
index a3aef405..17f4f70b 100644
--- a/app/crypto/Makefile
+++ b/app/crypto/Makefile
@@ -15,6 +15,8 @@ ifndef PDIR
 GEN_LIBS = libcrypto.a
 endif
 
+STD_CFLAGS=-std=gnu11 -Wimplicit
+
 #############################################################
 # Configuration i.e. compile options etc.
 # Target specific stuff (defines etc.) goes in here!