diff --git a/Makefile b/Makefile
index 5282b5d..ee93aba 100644
--- a/Makefile
+++ b/Makefile
@@ -16,7 +16,7 @@ ifeq ($(uname_S),SunOS)
   STLIBNAME?=libhiredis.a
   STLIB_MAKE_CMD?=ar rcs ${STLIBNAME} ${OBJ}
 else ifeq ($(uname_S),Darwin)
-  CFLAGS?=-std=c99 -pedantic $(OPTIMIZATION) -fPIC -Wall -W -Wwrite-strings $(ARCH) $(PROF)
+  CFLAGS?=-std=c99 -pedantic $(OPTIMIZATION) -fPIC -Wall -W -Wstrict-prototypes -Wwrite-strings $(ARCH) $(PROF)
   CCLINK?=-lm -pthread
   LDFLAGS?=-L. -Wl,-rpath,.
   OBJARCH?=-arch i386 -arch x86_64
@@ -25,7 +25,7 @@ else ifeq ($(uname_S),Darwin)
   STLIBNAME?=libhiredis.a
   STLIB_MAKE_CMD?=libtool -static -o ${STLIBNAME} - ${OBJ}
 else
-  CFLAGS?=-std=c99 -pedantic $(OPTIMIZATION) -fPIC -Wall -W -Wwrite-strings $(ARCH) $(PROF)
+  CFLAGS?=-std=c99 -pedantic $(OPTIMIZATION) -fPIC -Wall -W -Wstrict-prototypes -Wwrite-strings $(ARCH) $(PROF)
   CCLINK?=-lm -pthread
   LDFLAGS?=-L. -Wl,-rpath,.
   DYLIBNAME?=libhiredis.so
diff --git a/hiredis.c b/hiredis.c
index 9ff0b97..243ea75 100644
--- a/hiredis.c
+++ b/hiredis.c
@@ -434,7 +434,7 @@ static int processItem(redisReader *r) {
     }
 }
 
-void *redisReplyReaderCreate() {
+void *redisReplyReaderCreate(void) {
     redisReader *r = calloc(sizeof(redisReader),1);
     r->error = NULL;
     r->fn = &defaultFunctions;
@@ -793,7 +793,7 @@ void __redisSetError(redisContext *c, int type, const sds errstr) {
     }
 }
 
-static redisContext *redisContextInit() {
+static redisContext *redisContextInit(void) {
     redisContext *c = calloc(sizeof(redisContext),1);
     c->err = 0;
     c->errstr = NULL;
diff --git a/hiredis.h b/hiredis.h
index 8fdca4a..c33606b 100644
--- a/hiredis.h
+++ b/hiredis.h
@@ -129,7 +129,7 @@ typedef struct redisContext {
 } redisContext;
 
 void freeReplyObject(void *reply);
-void *redisReplyReaderCreate();
+void *redisReplyReaderCreate(void);
 int redisReplyReaderSetReplyObjectFunctions(void *reader, redisReplyObjectFunctions *fn);
 int redisReplyReaderSetPrivdata(void *reader, void *privdata);
 void *redisReplyReaderGetObject(void *reader);
diff --git a/sds.h b/sds.h
index c64e8d5..eb41eb7 100644
--- a/sds.h
+++ b/sds.h
@@ -44,7 +44,7 @@ struct sdshdr {
 
 sds sdsnewlen(const void *init, size_t initlen);
 sds sdsnew(const char *init);
-sds sdsempty();
+sds sdsempty(void);
 size_t sdslen(const sds s);
 sds sdsdup(const sds s);
 void sdsfree(sds s);
diff --git a/test.c b/test.c
index 9ab0354..8017356 100644
--- a/test.c
+++ b/test.c
@@ -32,7 +32,7 @@ static void __connect(redisContext **target) {
     }
 }
 
-static void test_format_commands() {
+static void test_format_commands(void) {
     char *cmd;
     int len;
 
@@ -116,7 +116,7 @@ static void test_format_commands() {
     free(cmd);
 }
 
-static void test_blocking_connection() {
+static void test_blocking_connection(void) {
     redisContext *c;
     redisReply *reply;
     int major, minor;
@@ -261,7 +261,7 @@ static void test_blocking_connection() {
     __connect(&c);
 }
 
-static void test_reply_reader() {
+static void test_reply_reader(void) {
     void *reader;
     void *reply;
     char *err;
@@ -320,7 +320,7 @@ static void test_reply_reader() {
     redisReplyReaderFree(reader);
 }
 
-static void test_throughput() {
+static void test_throughput(void) {
     int i;
     long long t1, t2;
     redisContext *c = blocking_context;
@@ -354,7 +354,7 @@ static void test_throughput() {
     printf("\t(1000x LRANGE with 500 elements: %.2fs)\n", (t2-t1)/1000000.0);
 }
 
-static void cleanup() {
+static void cleanup(void) {
     redisContext *c = blocking_context;
     redisReply *reply;