diff --git a/programs/fuzz/fuzz_dtlsserver.c b/programs/fuzz/fuzz_dtlsserver.c
index 9e9fe8e..4cde1fe 100644
--- a/programs/fuzz/fuzz_dtlsserver.c
+++ b/programs/fuzz/fuzz_dtlsserver.c
@@ -11,7 +11,10 @@
 #include "mbedtls/ssl_cookie.h"
 
 
-#ifdef MBEDTLS_SSL_SRV_C
+#if defined(MBEDTLS_SSL_SRV_C) && \
+    defined(MBEDTLS_ENTROPY_C) && \
+    defined(MBEDTLS_CTR_DRBG_C) && \
+    defined(MBEDTLS_TIMING_C)
 const char *pers = "fuzz_dtlsserver";
 const unsigned char client_ip[4] = {0x7F, 0, 0, 1};
 static int initialized = 0;
@@ -19,11 +22,15 @@
 static mbedtls_x509_crt srvcert;
 static mbedtls_pk_context pkey;
 #endif
-#endif // MBEDTLS_SSL_SRV_C
+#endif
 #endif // MBEDTLS_SSL_PROTO_DTLS
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
-#if defined(MBEDTLS_SSL_PROTO_DTLS) && defined(MBEDTLS_SSL_SRV_C)
+#if defined(MBEDTLS_SSL_PROTO_DTLS) && \
+    defined(MBEDTLS_SSL_SRV_C) && \
+    defined(MBEDTLS_ENTROPY_C) && \
+    defined(MBEDTLS_CTR_DRBG_C) && \
+    defined(MBEDTLS_TIMING_C)
     int ret;
     size_t len;
     mbedtls_ssl_context ssl;