diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 629051b..5010193 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.c
@@ -36,11 +36,11 @@
 #if !defined(POLARSSL_X509_CRT_WRITE_C) ||                                  \
     !defined(POLARSSL_X509_CRT_PARSE_C) || !defined(POLARSSL_FS_IO) ||      \
     !defined(POLARSSL_ENTROPY_C) || !defined(POLARSSL_CTR_DRBG_C) ||        \
-    !defined(POLARSSL_ERROR_C)
+    !defined(POLARSSL_ERROR_C) || !defined(POLARSSL_SHA256_C)
 int main( void )
 {
     polarssl_printf( "POLARSSL_X509_CRT_WRITE_C and/or POLARSSL_X509_CRT_PARSE_C and/or "
-            "POLARSSL_FS_IO and/or "
+            "POLARSSL_FS_IO and/or POLARSSL_SHA256_C and_or "
             "POLARSSL_ENTROPY_C and/or POLARSSL_CTR_DRBG_C and/or "
             "POLARSSL_ERROR_C not defined.\n");
     return( 0 );