diff --git a/cmd/tools/vtest-self.v b/cmd/tools/vtest-self.v
index 0575416e5d94c7..bf9594fc0dfd21 100644
--- a/cmd/tools/vtest-self.v
+++ b/cmd/tools/vtest-self.v
@@ -49,11 +49,11 @@ const (
 		'vlib/io/os_file_reader_test.v',
 		'vlib/os/process_test.v',
 		'vlib/os/file_test.v',
-		'vlib/os/notify/notify_test.v',
+		'vlib/os/notify/notify_test.c.v',
 		'vlib/os/filepath_test.v',
 		'vlib/os/environment_test.v',
 		'vlib/os/glob_test.v',
-		'vlib/os/os_test.v',
+		'vlib/os/os_test.c.v',
 		'vlib/rand/random_numbers_test.v',
 		'vlib/rand/wyrand/wyrand_test.v',
 		'vlib/runtime/runtime_test.v',
@@ -63,7 +63,7 @@ const (
 		'vlib/sync/waitgroup_test.v',
 		'vlib/sync/pool/pool_test.v',
 		'vlib/strings/builder_test.v',
-		'vlib/strconv/atof_test.v',
+		'vlib/strconv/atof_test.c.v',
 		'vlib/strconv/atoi_test.v',
 		'vlib/strconv/f32_f64_to_string_test.v',
 		'vlib/strconv/format_test.v',
diff --git a/vlib/os/notify/notify_test.v b/vlib/os/notify/notify_test.c.v
similarity index 100%
rename from vlib/os/notify/notify_test.v
rename to vlib/os/notify/notify_test.c.v
diff --git a/vlib/os/os_test.v b/vlib/os/os_test.c.v
similarity index 100%
rename from vlib/os/os_test.v
rename to vlib/os/os_test.c.v
diff --git a/vlib/picohttpparser/response.v b/vlib/picohttpparser/response.c.v
similarity index 97%
rename from vlib/picohttpparser/response.v
rename to vlib/picohttpparser/response.c.v
index f6b073ac7b21ba..c66ebcc2220ba6 100644
--- a/vlib/picohttpparser/response.v
+++ b/vlib/picohttpparser/response.c.v
@@ -12,7 +12,7 @@ pub mut:
 [inline]
 pub fn (mut r Response) write_string(s string) {
 	unsafe {
-		C.memcpy(r.buf, s.str, s.len)
+		vmemcpy(r.buf, s.str, s.len)
 		r.buf += s.len
 	}
 }
@@ -36,7 +36,7 @@ pub fn (mut r Response) header(k string, v string) &Response {
 pub fn (mut r Response) header_date() &Response {
 	r.write_string('Date: ')
 	unsafe {
-		C.memcpy(r.buf, r.date, 29)
+		vmemcpy(r.buf, r.date, 29)
 		r.buf += 29
 	}
 	r.write_string('\r\n')
diff --git a/vlib/sokol/audio/audio.v b/vlib/sokol/audio/audio.c.v
similarity index 100%
rename from vlib/sokol/audio/audio.v
rename to vlib/sokol/audio/audio.c.v
diff --git a/vlib/sokol/memory/memory.v b/vlib/sokol/memory/memory.c.v
similarity index 100%
rename from vlib/sokol/memory/memory.v
rename to vlib/sokol/memory/memory.c.v
diff --git a/vlib/strconv/atof_test.v b/vlib/strconv/atof_test.c.v
similarity index 100%
rename from vlib/strconv/atof_test.v
rename to vlib/strconv/atof_test.c.v