diff --git a/library/Makefile b/library/Makefile
index 30bc96f..921b68e 100644
--- a/library/Makefile
+++ b/library/Makefile
@@ -92,9 +92,9 @@
 # For files generated by the parent project (Mbed TLS) when building Mbed
 # Crypto as a submodule, ensure that the parent project instance is used.
 ifeq ($(USE_CRYPTO_SUBMODULE), 1)
-OBJS_CRYPTO += ../../library/error.o
-OBJS_CRYPTO += ../../library/version.o
-OBJS_CRYPTO += ../../library/version_features.o
+OBJS_CRYPTO += $(patsubst %.c,%.o, $(realpath ../../library/error.c))
+OBJS_CRYPTO += $(patsubst %.c,%.o, $(realpath ../../library/version.c))
+OBJS_CRYPTO += $(patsubst %.c,%.o, $(realpath ../../library/version_features.c))
 else
 OBJS_CRYPTO += error.o
 OBJS_CRYPTO += version.o