small webassembly fix

compiler/main.v

@@ -909,7 +909,7 @@ fn test_v() {
 		relative_file := dot_relative_file.replace('./', '')
 		file := os.realpath( relative_file )
 		tmpcfilepath := file.replace('_test.v', '_test.tmp.c')
-		print(relative_file + ' ')    
+		print(relative_file + ' ')
 		r := os.exec('$vexe $joined_args -debug $file') or {
 			panic('failed on $file')
 		}

vlib/os/os.v

@@ -114,7 +114,7 @@ fn parse_windows_cmd_line(cmd byteptr) []string {
 // read_file reads the file in `path` and returns the contents.
 pub fn read_file(path string) ?string {
 	mode := 'rb'
-	mut fp := &C.FILE{}
+	mut fp := &C.FILE{!}
 	$if windows {
 		fp = C._wfopen(path.to_wide(), mode.to_wide())
 	} $else {
@@ -162,7 +162,7 @@ pub fn read_lines(path string) []string {
 	mut buf := malloc(buf_len)
 
 	mode := 'rb'
-	mut fp := &C.FILE{}
+	mut fp := &C.FILE{!}
 	$if windows {
 		fp = C._wfopen(path.to_wide(), mode.to_wide())
 	} $else {