diff --git a/extmod/moduheapq.c b/extmod/moduheapq.c
index bdaf191e9..1574eb862 100644
--- a/extmod/moduheapq.c
+++ b/extmod/moduheapq.c
@@ -31,14 +31,14 @@
 
 // the algorithm here is modelled on CPython's heapq.py
 
-STATIC mp_obj_list_t *get_heap(mp_obj_t heap_in) {
+STATIC mp_obj_list_t *uheapq_get_heap(mp_obj_t heap_in) {
     if (!mp_obj_is_type(heap_in, &mp_type_list)) {
         mp_raise_TypeError("heap must be a list");
     }
     return MP_OBJ_TO_PTR(heap_in);
 }
 
-STATIC void heap_siftdown(mp_obj_list_t *heap, mp_uint_t start_pos, mp_uint_t pos) {
+STATIC void uheapq_heap_siftdown(mp_obj_list_t *heap, mp_uint_t start_pos, mp_uint_t pos) {
     mp_obj_t item = heap->items[pos];
     while (pos > start_pos) {
         mp_uint_t parent_pos = (pos - 1) >> 1;
@@ -53,7 +53,7 @@ STATIC void heap_siftdown(mp_obj_list_t *heap, mp_uint_t start_pos, mp_uint_t po
     heap->items[pos] = item;
 }
 
-STATIC void heap_siftup(mp_obj_list_t *heap, mp_uint_t pos) {
+STATIC void uheapq_heap_siftup(mp_obj_list_t *heap, mp_uint_t pos) {
     mp_uint_t start_pos = pos;
     mp_uint_t end_pos = heap->len;
     mp_obj_t item = heap->items[pos];
@@ -67,19 +67,19 @@ STATIC void heap_siftup(mp_obj_list_t *heap, mp_uint_t pos) {
         pos = child_pos;
     }
     heap->items[pos] = item;
-    heap_siftdown(heap, start_pos, pos);
+    uheapq_heap_siftdown(heap, start_pos, pos);
 }
 
 STATIC mp_obj_t mod_uheapq_heappush(mp_obj_t heap_in, mp_obj_t item) {
-    mp_obj_list_t *heap = get_heap(heap_in);
+    mp_obj_list_t *heap = uheapq_get_heap(heap_in);
     mp_obj_list_append(heap_in, item);
-    heap_siftdown(heap, 0, heap->len - 1);
+    uheapq_heap_siftdown(heap, 0, heap->len - 1);
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_uheapq_heappush_obj, mod_uheapq_heappush);
 
 STATIC mp_obj_t mod_uheapq_heappop(mp_obj_t heap_in) {
-    mp_obj_list_t *heap = get_heap(heap_in);
+    mp_obj_list_t *heap = uheapq_get_heap(heap_in);
     if (heap->len == 0) {
         nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "empty heap"));
     }
@@ -88,16 +88,16 @@ STATIC mp_obj_t mod_uheapq_heappop(mp_obj_t heap_in) {
     heap->items[0] = heap->items[heap->len];
     heap->items[heap->len] = MP_OBJ_NULL; // so we don't retain a pointer
     if (heap->len) {
-        heap_siftup(heap, 0);
+        uheapq_heap_siftup(heap, 0);
     }
     return item;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_uheapq_heappop_obj, mod_uheapq_heappop);
 
 STATIC mp_obj_t mod_uheapq_heapify(mp_obj_t heap_in) {
-    mp_obj_list_t *heap = get_heap(heap_in);
+    mp_obj_list_t *heap = uheapq_get_heap(heap_in);
     for (mp_uint_t i = heap->len / 2; i > 0;) {
-        heap_siftup(heap, --i);
+        uheapq_heap_siftup(heap, --i);
     }
     return mp_const_none;
 }
diff --git a/extmod/modussl_axtls.c b/extmod/modussl_axtls.c
index b559b1358..2ea175728 100644
--- a/extmod/modussl_axtls.c
+++ b/extmod/modussl_axtls.c
@@ -54,7 +54,7 @@ struct ssl_args {
 
 STATIC const mp_obj_type_t ussl_socket_type;
 
-STATIC mp_obj_ssl_socket_t *socket_new(mp_obj_t sock, struct ssl_args *args) {
+STATIC mp_obj_ssl_socket_t *ussl_socket_new(mp_obj_t sock, struct ssl_args *args) {
 #if MICROPY_PY_USSL_FINALISER
     mp_obj_ssl_socket_t *o = m_new_obj_with_finaliser(mp_obj_ssl_socket_t);
 #else
@@ -118,13 +118,13 @@ STATIC mp_obj_ssl_socket_t *socket_new(mp_obj_t sock, struct ssl_args *args) {
     return o;
 }
 
-STATIC void socket_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
+STATIC void ussl_socket_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     (void)kind;
     mp_obj_ssl_socket_t *self = MP_OBJ_TO_PTR(self_in);
     mp_printf(print, "<_SSLSocket %p>", self->ssl_sock);
 }
 
-STATIC mp_uint_t socket_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *errcode) {
+STATIC mp_uint_t ussl_socket_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *errcode) {
     mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
 
     if (o->ssl_sock == NULL) {
@@ -173,7 +173,7 @@ eagain:
     return size;
 }
 
-STATIC mp_uint_t socket_write(mp_obj_t o_in, const void *buf, mp_uint_t size, int *errcode) {
+STATIC mp_uint_t ussl_socket_write(mp_obj_t o_in, const void *buf, mp_uint_t size, int *errcode) {
     mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
 
     if (o->ssl_sock == NULL) {
@@ -189,7 +189,7 @@ STATIC mp_uint_t socket_write(mp_obj_t o_in, const void *buf, mp_uint_t size, in
     return r;
 }
 
-STATIC mp_uint_t socket_ioctl(mp_obj_t o_in, mp_uint_t request, uintptr_t arg, int *errcode) {
+STATIC mp_uint_t ussl_socket_ioctl(mp_obj_t o_in, mp_uint_t request, uintptr_t arg, int *errcode) {
     mp_obj_ssl_socket_t *self = MP_OBJ_TO_PTR(o_in);
     if (request == MP_STREAM_CLOSE && self->ssl_sock != NULL) {
         ssl_free(self->ssl_sock);
@@ -200,7 +200,7 @@ STATIC mp_uint_t socket_ioctl(mp_obj_t o_in, mp_uint_t request, uintptr_t arg, i
     return mp_get_stream(self->sock)->ioctl(self->sock, request, arg, errcode);
 }
 
-STATIC mp_obj_t socket_setblocking(mp_obj_t self_in, mp_obj_t flag_in) {
+STATIC mp_obj_t ussl_socket_setblocking(mp_obj_t self_in, mp_obj_t flag_in) {
     mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(self_in);
     mp_obj_t sock = o->sock;
     mp_obj_t dest[3];
@@ -210,14 +210,14 @@ STATIC mp_obj_t socket_setblocking(mp_obj_t self_in, mp_obj_t flag_in) {
     o->blocking = mp_obj_is_true(flag_in);
     return res;
 }
-STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_setblocking_obj, socket_setblocking);
+STATIC MP_DEFINE_CONST_FUN_OBJ_2(ussl_socket_setblocking_obj, ussl_socket_setblocking);
 
 STATIC const mp_rom_map_elem_t ussl_socket_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
     { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
     { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
     { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
-    { MP_ROM_QSTR(MP_QSTR_setblocking), MP_ROM_PTR(&socket_setblocking_obj) },
+    { MP_ROM_QSTR(MP_QSTR_setblocking), MP_ROM_PTR(&ussl_socket_setblocking_obj) },
     { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&mp_stream_close_obj) },
 #if MICROPY_PY_USSL_FINALISER
     { MP_ROM_QSTR(MP_QSTR___del__), MP_ROM_PTR(&mp_stream_close_obj) },
@@ -227,16 +227,16 @@ STATIC const mp_rom_map_elem_t ussl_socket_locals_dict_table[] = {
 STATIC MP_DEFINE_CONST_DICT(ussl_socket_locals_dict, ussl_socket_locals_dict_table);
 
 STATIC const mp_stream_p_t ussl_socket_stream_p = {
-    .read = socket_read,
-    .write = socket_write,
-    .ioctl = socket_ioctl,
+    .read = ussl_socket_read,
+    .write = ussl_socket_write,
+    .ioctl = ussl_socket_ioctl,
 };
 
 STATIC const mp_obj_type_t ussl_socket_type = {
     { &mp_type_type },
     // Save on qstr's, reuse same as for module
     .name = MP_QSTR_ussl,
-    .print = socket_print,
+    .print = ussl_socket_print,
     .getiter = NULL,
     .iternext = NULL,
     .protocol = &ussl_socket_stream_p,
@@ -260,7 +260,7 @@ STATIC mp_obj_t mod_ssl_wrap_socket(size_t n_args, const mp_obj_t *pos_args, mp_
     mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args,
         MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t*)&args);
 
-    return MP_OBJ_FROM_PTR(socket_new(sock, &args));
+    return MP_OBJ_FROM_PTR(ussl_socket_new(sock, &args));
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_ssl_wrap_socket_obj, 1, mod_ssl_wrap_socket);
 
diff --git a/extmod/modutimeq.c b/extmod/modutimeq.c
index 26f5a78fa..28a2a70c5 100644
--- a/extmod/modutimeq.c
+++ b/extmod/modutimeq.c
@@ -55,7 +55,7 @@ typedef struct _mp_obj_utimeq_t {
 
 STATIC mp_uint_t utimeq_id;
 
-STATIC mp_obj_utimeq_t *get_heap(mp_obj_t heap_in) {
+STATIC mp_obj_utimeq_t *utimeq_get_heap(mp_obj_t heap_in) {
     return MP_OBJ_TO_PTR(heap_in);
 }
 
@@ -85,7 +85,7 @@ STATIC mp_obj_t utimeq_make_new(const mp_obj_type_t *type, size_t n_args, size_t
     return MP_OBJ_FROM_PTR(o);
 }
 
-STATIC void heap_siftdown(mp_obj_utimeq_t *heap, mp_uint_t start_pos, mp_uint_t pos) {
+STATIC void utimeq_heap_siftdown(mp_obj_utimeq_t *heap, mp_uint_t start_pos, mp_uint_t pos) {
     struct qentry item = heap->items[pos];
     while (pos > start_pos) {
         mp_uint_t parent_pos = (pos - 1) >> 1;
@@ -101,7 +101,7 @@ STATIC void heap_siftdown(mp_obj_utimeq_t *heap, mp_uint_t start_pos, mp_uint_t
     heap->items[pos] = item;
 }
 
-STATIC void heap_siftup(mp_obj_utimeq_t *heap, mp_uint_t pos) {
+STATIC void utimeq_heap_siftup(mp_obj_utimeq_t *heap, mp_uint_t pos) {
     mp_uint_t start_pos = pos;
     mp_uint_t end_pos = heap->len;
     struct qentry item = heap->items[pos];
@@ -118,13 +118,13 @@ STATIC void heap_siftup(mp_obj_utimeq_t *heap, mp_uint_t pos) {
         pos = child_pos;
     }
     heap->items[pos] = item;
-    heap_siftdown(heap, start_pos, pos);
+    utimeq_heap_siftdown(heap, start_pos, pos);
 }
 
 STATIC mp_obj_t mod_utimeq_heappush(size_t n_args, const mp_obj_t *args) {
     (void)n_args;
     mp_obj_t heap_in = args[0];
-    mp_obj_utimeq_t *heap = get_heap(heap_in);
+    mp_obj_utimeq_t *heap = utimeq_get_heap(heap_in);
     if (heap->len == heap->alloc) {
         mp_raise_msg(&mp_type_IndexError, "queue overflow");
     }
@@ -133,14 +133,14 @@ STATIC mp_obj_t mod_utimeq_heappush(size_t n_args, const mp_obj_t *args) {
     heap->items[l].id = utimeq_id++;
     heap->items[l].callback = args[2];
     heap->items[l].args = args[3];
-    heap_siftdown(heap, 0, heap->len);
+    utimeq_heap_siftdown(heap, 0, heap->len);
     heap->len++;
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_utimeq_heappush_obj, 4, 4, mod_utimeq_heappush);
 
 STATIC mp_obj_t mod_utimeq_heappop(mp_obj_t heap_in, mp_obj_t list_ref) {
-    mp_obj_utimeq_t *heap = get_heap(heap_in);
+    mp_obj_utimeq_t *heap = utimeq_get_heap(heap_in);
     if (heap->len == 0) {
         nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "empty heap"));
     }
@@ -158,14 +158,14 @@ STATIC mp_obj_t mod_utimeq_heappop(mp_obj_t heap_in, mp_obj_t list_ref) {
     heap->items[heap->len].callback = MP_OBJ_NULL; // so we don't retain a pointer
     heap->items[heap->len].args = MP_OBJ_NULL;
     if (heap->len) {
-        heap_siftup(heap, 0);
+        utimeq_heap_siftup(heap, 0);
     }
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_utimeq_heappop_obj, mod_utimeq_heappop);
 
 STATIC mp_obj_t mod_utimeq_peektime(mp_obj_t heap_in) {
-    mp_obj_utimeq_t *heap = get_heap(heap_in);
+    mp_obj_utimeq_t *heap = utimeq_get_heap(heap_in);
     if (heap->len == 0) {
         nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "empty heap"));
     }
@@ -177,7 +177,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_utimeq_peektime_obj, mod_utimeq_peektime);
 
 #if DEBUG
 STATIC mp_obj_t mod_utimeq_dump(mp_obj_t heap_in) {
-    mp_obj_utimeq_t *heap = get_heap(heap_in);
+    mp_obj_utimeq_t *heap = utimeq_get_heap(heap_in);
     for (int i = 0; i < heap->len; i++) {
         printf(UINT_FMT "\t%p\t%p\n", heap->items[i].time,
             MP_OBJ_TO_PTR(heap->items[i].callback), MP_OBJ_TO_PTR(heap->items[i].args));
diff --git a/extmod/vfs_fat_file.c b/extmod/vfs_fat_file.c
index f7b9331b8..fb1e582f2 100644
--- a/extmod/vfs_fat_file.c
+++ b/extmod/vfs_fat_file.c
@@ -219,7 +219,7 @@ STATIC mp_obj_t file_obj_make_new(const mp_obj_type_t *type, size_t n_args, size
 
 // TODO gc hook to close the file if not already closed
 
-STATIC const mp_rom_map_elem_t rawfile_locals_dict_table[] = {
+STATIC const mp_rom_map_elem_t vfs_fat_rawfile_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
     { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
     { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
@@ -234,10 +234,10 @@ STATIC const mp_rom_map_elem_t rawfile_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&file_obj___exit___obj) },
 };
 
-STATIC MP_DEFINE_CONST_DICT(rawfile_locals_dict, rawfile_locals_dict_table);
+STATIC MP_DEFINE_CONST_DICT(vfs_fat_rawfile_locals_dict, vfs_fat_rawfile_locals_dict_table);
 
 #if MICROPY_PY_IO_FILEIO
-STATIC const mp_stream_p_t fileio_stream_p = {
+STATIC const mp_stream_p_t vfs_fat_fileio_stream_p = {
     .read = file_obj_read,
     .write = file_obj_write,
     .ioctl = file_obj_ioctl,
@@ -250,12 +250,12 @@ const mp_obj_type_t mp_type_vfs_fat_fileio = {
     .make_new = file_obj_make_new,
     .getiter = mp_identity_getiter,
     .iternext = mp_stream_unbuffered_iter,
-    .protocol = &fileio_stream_p,
-    .locals_dict = (mp_obj_dict_t*)&rawfile_locals_dict,
+    .protocol = &vfs_fat_fileio_stream_p,
+    .locals_dict = (mp_obj_dict_t*)&vfs_fat_rawfile_locals_dict,
 };
 #endif
 
-STATIC const mp_stream_p_t textio_stream_p = {
+STATIC const mp_stream_p_t vfs_fat_textio_stream_p = {
     .read = file_obj_read,
     .write = file_obj_write,
     .ioctl = file_obj_ioctl,
@@ -269,8 +269,8 @@ const mp_obj_type_t mp_type_vfs_fat_textio = {
     .make_new = file_obj_make_new,
     .getiter = mp_identity_getiter,
     .iternext = mp_stream_unbuffered_iter,
-    .protocol = &textio_stream_p,
-    .locals_dict = (mp_obj_dict_t*)&rawfile_locals_dict,
+    .protocol = &vfs_fat_textio_stream_p,
+    .locals_dict = (mp_obj_dict_t*)&vfs_fat_rawfile_locals_dict,
 };
 
 // Factory function for I/O stream classes
diff --git a/extmod/vfs_posix_file.c b/extmod/vfs_posix_file.c
index 44cb85dcc..6f7ce814f 100644
--- a/extmod/vfs_posix_file.c
+++ b/extmod/vfs_posix_file.c
@@ -200,7 +200,7 @@ STATIC mp_uint_t vfs_posix_file_ioctl(mp_obj_t o_in, mp_uint_t request, uintptr_
     }
 }
 
-STATIC const mp_rom_map_elem_t rawfile_locals_dict_table[] = {
+STATIC const mp_rom_map_elem_t vfs_posix_rawfile_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_fileno), MP_ROM_PTR(&vfs_posix_file_fileno_obj) },
     { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
     { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
@@ -215,10 +215,10 @@ STATIC const mp_rom_map_elem_t rawfile_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&vfs_posix_file___exit___obj) },
 };
 
-STATIC MP_DEFINE_CONST_DICT(rawfile_locals_dict, rawfile_locals_dict_table);
+STATIC MP_DEFINE_CONST_DICT(vfs_posix_rawfile_locals_dict, vfs_posix_rawfile_locals_dict_table);
 
 #if MICROPY_PY_IO_FILEIO
-STATIC const mp_stream_p_t fileio_stream_p = {
+STATIC const mp_stream_p_t vfs_posix_fileio_stream_p = {
     .read = vfs_posix_file_read,
     .write = vfs_posix_file_write,
     .ioctl = vfs_posix_file_ioctl,
@@ -231,12 +231,12 @@ const mp_obj_type_t mp_type_vfs_posix_fileio = {
     .make_new = vfs_posix_file_make_new,
     .getiter = mp_identity_getiter,
     .iternext = mp_stream_unbuffered_iter,
-    .protocol = &fileio_stream_p,
-    .locals_dict = (mp_obj_dict_t*)&rawfile_locals_dict,
+    .protocol = &vfs_posix_fileio_stream_p,
+    .locals_dict = (mp_obj_dict_t*)&vfs_posix_rawfile_locals_dict,
 };
 #endif
 
-STATIC const mp_stream_p_t textio_stream_p = {
+STATIC const mp_stream_p_t vfs_posix_textio_stream_p = {
     .read = vfs_posix_file_read,
     .write = vfs_posix_file_write,
     .ioctl = vfs_posix_file_ioctl,
@@ -250,8 +250,8 @@ const mp_obj_type_t mp_type_vfs_posix_textio = {
     .make_new = vfs_posix_file_make_new,
     .getiter = mp_identity_getiter,
     .iternext = mp_stream_unbuffered_iter,
-    .protocol = &textio_stream_p,
-    .locals_dict = (mp_obj_dict_t*)&rawfile_locals_dict,
+    .protocol = &vfs_posix_textio_stream_p,
+    .locals_dict = (mp_obj_dict_t*)&vfs_posix_rawfile_locals_dict,
 };
 
 const mp_obj_vfs_posix_file_t mp_sys_stdin_obj  = {{&mp_type_textio}, STDIN_FILENO};