diff --git a/http.go b/http.go
index 0f0600d..275ab91 100644
--- a/http.go
+++ b/http.go
@@ -335,7 +335,7 @@ func getSmartSubtransportStreamInterface(_s *C.git_smart_subtransport_stream) (S
 }
 
 //export smartSubtransportRead
-func smartSubtransportRead(s *C.git_smart_subtransport_stream, data unsafe.Pointer, l C.size_t, read *C.size_t) C.int {
+func smartSubtransportRead(s *C.git_smart_subtransport_stream, data *C.char, l C.size_t, read *C.size_t) C.int {
 	stream, err := getSmartSubtransportStreamInterface(s)
 	if err != nil {
 		return setLibgit2Error(err)
@@ -345,7 +345,7 @@ func smartSubtransportRead(s *C.git_smart_subtransport_stream, data unsafe.Point
 	header := (*reflect.SliceHeader)(unsafe.Pointer(&p))
 	header.Cap = int(l)
 	header.Len = int(l)
-	header.Data = uintptr(data)
+	header.Data = uintptr(unsafe.Pointer(data))
 
 	n, err := stream.Read(p)
 	if err != nil {
diff --git a/wrapper.c b/wrapper.c
index d498284..aafe901 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -198,7 +198,9 @@ int _go_git_transport_smart(git_transport **out, git_remote *owner)
 
 void _go_git_setup_smart_subtransport(managed_smart_subtransport *t, void *ptr)
 {
-	t->parent.action = httpAction;
+	typedef int (*transport_action)(git_smart_subtransport_stream **out, git_smart_subtransport *transport, const char *url, git_smart_service_t action);
+
+	t->parent.action = (transport_action)httpAction;
 	t->parent.close = httpClose;
 	t->parent.free = httpFree;
 
@@ -207,8 +209,10 @@ void _go_git_setup_smart_subtransport(managed_smart_subtransport *t, void *ptr)
 
 void _go_git_setup_smart_subtransport_stream(managed_smart_subtransport_stream *s, void *ptr)
 {
+	typedef int (*transport_stream_write)(git_smart_subtransport_stream *stream, const char *buffer, size_t len);
+
 	s->parent.read = smartSubtransportRead;
-	s->parent.write = smartSubtransportWrite;
+	s->parent.write = (transport_stream_write)smartSubtransportWrite;
 	s->parent.free = smartSubtransportFree;
 
 	s->ptr = ptr;