diff --git a/mongoose.c b/mongoose.c
index 236d5b27..a74a66d7 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -11054,7 +11054,7 @@ uint32_t mg_coap_compose(struct mg_coap_message *cm, struct mbuf *io) {
   prev_opt_number = 0;
   while (opt != NULL) {
     uint8_t delta_base = 0, length_base = 0;
-    uint16_t delta_ext, length_ext;
+    uint16_t delta_ext = 0, length_ext = 0;
 
     size_t opt_delta_len =
         coap_split_opt(opt->number - prev_opt_number, &delta_base, &delta_ext);
diff --git a/mongoose.h b/mongoose.h
index 4a6c13b6..3684b4d1 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -475,6 +475,7 @@ typedef struct stat cs_stat_t;
 #define INT64_X_FMT PRIx64
 #define __cdecl
 #define _FILE_OFFSET_BITS 32
+#define fineno(x) -1
 
 #define MG_LWIP 1