diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5b57637..f3f05bd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,6 +3,7 @@
 add_definitions (-DMCTP_LOG_STDERR)
 add_definitions (-DMCTP_HAVE_FILEIO)
 add_definitions (-DMCTP_HAVE_STDIO)
+add_definitions (-DMCTP_DEFAULT_ALLOC)
 
 add_library (libmctp STATIC alloc.c core.c log.c libmctp.h serial.c)