diff --git a/Makefile b/Makefile
index 4b3f63aa..4bedd3d9 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 SRCS = mongoose.c test/unit_test.c test/packed_fs.c
 HDRS = $(wildcard src/*.h)
 DEFS ?= -DMG_MAX_HTTP_HEADERS=7 -DMG_ENABLE_LINES -DMG_ENABLE_PACKED_FS=1
-WARN ?= -W -Wall -Werror -Wshadow -Wdouble-promotion -fno-common -Wconversion -Wundef
+WARN ?= -W -Wall -Werror -Wshadow -Wdouble-promotion -Wmissing-prototypes -Wstrict-prototypes -fno-common -Wconversion -Wundef
 OPTS ?= -O3 -g3
 INCS ?= -Isrc -I.
 SSL ?= MBEDTLS
@@ -62,7 +62,7 @@ unpacked:
 	$(CC) -I. mongoose.c test/unit_test.c -o unit_test
 
 fuzzer: mongoose.c mongoose.h Makefile test/fuzz.c
-	clang mongoose.c test/fuzz.c $(WARN) $(INCS) -DMG_ENABLE_LINES -DMG_ENABLE_LOG=0 -fsanitize=fuzzer,signed-integer-overflow,address -g -o $@
+	clang++ mongoose.c test/fuzz.c $(WARN) $(INCS) $(TFLAGS) $(EXTRA) -DMG_ENABLE_LINES -DMG_ENABLE_LOG=0 -fsanitize=fuzzer,signed-integer-overflow,address -Wno-deprecated -o $@
 
 fuzz: fuzzer
 	$(RUN) ./fuzzer
diff --git a/mongoose.c b/mongoose.c
index 0f2d9e67..b6b6bd04 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -632,6 +632,7 @@ struct packed_file {
 
 const char *mg_unpack(const char *path, size_t *size, time_t *mtime);
 const char *mg_unlist(size_t no);
+
 #if MG_ENABLE_PACKED_FS
 #else
 const char *mg_unpack(const char *path, size_t *size, time_t *mtime) {
diff --git a/mongoose.h b/mongoose.h
index ad0ee86a..a33eb424 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -562,6 +562,7 @@ size_t mg_asprintf(char **, size_t, const char *fmt, ...) PRINTF_LIKE(3, 4);
 size_t mg_vasprintf(char **buf, size_t size, const char *fmt, va_list ap);
 int mg_check_ip_acl(struct mg_str acl, uint32_t remote_ip);
 int64_t mg_to64(struct mg_str str);
+size_t mg_lld(char *buf, int64_t val, bool is_signed, bool is_hex);
 
 
 
@@ -1141,7 +1142,6 @@ void mg_resolve_cancel(struct mg_connection *);
 bool mg_dns_parse(const uint8_t *buf, size_t len, struct mg_dns_message *);
 size_t mg_dns_parse_rr(const uint8_t *buf, size_t len, size_t ofs,
                        bool is_question, struct mg_dns_rr *);
-size_t mg_dns_decode_name(const uint8_t *, size_t, size_t, char *, size_t);
 
 #ifdef __cplusplus
 }
diff --git a/src/dns.h b/src/dns.h
index bc723f46..a186f4d2 100644
--- a/src/dns.h
+++ b/src/dns.h
@@ -36,4 +36,3 @@ void mg_resolve_cancel(struct mg_connection *);
 bool mg_dns_parse(const uint8_t *buf, size_t len, struct mg_dns_message *);
 size_t mg_dns_parse_rr(const uint8_t *buf, size_t len, size_t ofs,
                        bool is_question, struct mg_dns_rr *);
-size_t mg_dns_decode_name(const uint8_t *, size_t, size_t, char *, size_t);
diff --git a/src/fs_packed.c b/src/fs_packed.c
index a7acaadd..179666fb 100644
--- a/src/fs_packed.c
+++ b/src/fs_packed.c
@@ -9,6 +9,7 @@ struct packed_file {
 
 const char *mg_unpack(const char *path, size_t *size, time_t *mtime);
 const char *mg_unlist(size_t no);
+
 #if MG_ENABLE_PACKED_FS
 #else
 const char *mg_unpack(const char *path, size_t *size, time_t *mtime) {
diff --git a/src/str.h b/src/str.h
index 53348b31..2dc752ed 100644
--- a/src/str.h
+++ b/src/str.h
@@ -41,3 +41,4 @@ size_t mg_asprintf(char **, size_t, const char *fmt, ...) PRINTF_LIKE(3, 4);
 size_t mg_vasprintf(char **buf, size_t size, const char *fmt, va_list ap);
 int mg_check_ip_acl(struct mg_str acl, uint32_t remote_ip);
 int64_t mg_to64(struct mg_str str);
+size_t mg_lld(char *buf, int64_t val, bool is_signed, bool is_hex);
diff --git a/test/mongoose_custom.c b/test/mongoose_custom.c
index cf251571..99a117b6 100644
--- a/test/mongoose_custom.c
+++ b/test/mongoose_custom.c
@@ -33,5 +33,6 @@ struct mg_connection *mg_mkpipe(struct mg_mgr *mgr, mg_event_handler_t fn,
   return NULL;
 }
 
+void _fini(void);
 void _fini(void) {
 }
diff --git a/test/pack.c b/test/pack.c
index 8cbce213..225da46b 100644
--- a/test/pack.c
+++ b/test/pack.c
@@ -25,6 +25,8 @@
 #include <sys/stat.h>
 
 static const char *code =
+    "const char *mg_unpack(const char *path, size_t *size, time_t *mtime);\n"
+    "const char *mg_unlist(size_t no);\n"
     "const char *mg_unlist(size_t no) {\n"
     "  return packed_files[no].name;\n"
     "}\n"