From 4a0367a63c28304f64c41624e15f584fcaa101c6 Mon Sep 17 00:00:00 2001
From: Nick Treleaven <n@trelsoft.com>
Date: Mon, 15 Feb 2021 15:15:52 +0000
Subject: [PATCH] vlib: add [unsafe] tag to more functions: tos,
 string_from_wide, strings.Builder: write_bytes, free (#8766)

---
 cmd/tools/vdoc/html.v            |  8 +++++---
 cmd/tools/vsymlink.v             |  4 ++--
 vlib/builtin/builtin_windows.c.v |  4 ++--
 vlib/builtin/rune.v              |  2 +-
 vlib/builtin/string.v            | 15 ++++++++++-----
 vlib/builtin/utf8.c.v            |  2 ++
 vlib/gg/gg.v                     |  2 +-
 vlib/json/json_primitives.v      |  2 +-
 vlib/net/http/backend_nix.c.v    |  6 +++---
 vlib/net/tcp_read_line.v         |  2 +-
 vlib/os/environment.c.v          |  2 +-
 vlib/os/os_c.v                   | 12 ++++++------
 vlib/os/os_nix.c.v               |  4 ++--
 vlib/os/os_windows.c.v           | 20 +++++++++++---------
 vlib/picoev/picoev.v             |  2 +-
 vlib/picohttpparser/request.v    | 18 ++++++++++++------
 vlib/regex/regex.v               |  2 +-
 vlib/sqlite/sqlite.v             |  4 ++--
 vlib/strconv/format.v            |  4 ++--
 vlib/strconv/utilities.v         |  2 +-
 vlib/strings/builder.v           |  5 +++--
 vlib/v/util/util.v               | 12 ++++++++----
 vlib/vweb/vweb.v                 |  2 +-
 vlib/x/websocket/handshake.v     |  2 +-
 vlib/x/websocket/utils.v         |  4 ++--
 25 files changed, 82 insertions(+), 60 deletions(-)

diff --git a/cmd/tools/vdoc/html.v b/cmd/tools/vdoc/html.v
index 24cdcb726e..7152edf3e5 100644
--- a/cmd/tools/vdoc/html.v
+++ b/cmd/tools/vdoc/html.v
@@ -292,8 +292,10 @@ fn (vd VDoc) gen_html(d doc.Doc) string {
 	}
 	modules_toc_str := modules_toc.str()
 	symbols_toc_str := symbols_toc.str()
-	modules_toc.free()
-	symbols_toc.free()
+	unsafe {
+		modules_toc.free()
+		symbols_toc.free()
+	}
 	return html_content.replace('{{ title }}', d.head.name).replace('{{ head_name }}',
 		header_name).replace('{{ version }}', version).replace('{{ light_icon }}', vd.assets['light_icon']).replace('{{ dark_icon }}',
 		vd.assets['dark_icon']).replace('{{ menu_icon }}', vd.assets['menu_icon']).replace('{{ head_assets }}',
@@ -471,7 +473,7 @@ fn doc_node_html(dn doc.DocNode, link string, head bool, include_examples bool,
 	dnw.writeln('</section>')
 	dnw_str := dnw.str()
 	defer {
-		dnw.free()
+		unsafe { dnw.free() }
 	}
 	return dnw_str
 }
diff --git a/cmd/tools/vsymlink.v b/cmd/tools/vsymlink.v
index 4eb2e0800f..82539299af 100644
--- a/cmd/tools/vsymlink.v
+++ b/cmd/tools/vsymlink.v
@@ -142,11 +142,11 @@ fn get_reg_value(reg_env_key voidptr, key string) ?string {
 	$if windows {
 		// query the value (shortcut the sizing step)
 		reg_value_size := 4095 // this is the max length (not for the registry, but for the system %PATH%)
-		mut reg_value := &u16(malloc(reg_value_size))
+		mut reg_value := unsafe { &u16(malloc(reg_value_size)) }
 		if C.RegQueryValueEx(reg_env_key, key.to_wide(), 0, 0, reg_value, &reg_value_size) != 0 {
 			return error('Unable to get registry value for "$key", try rerunning as an Administrator')
 		}
-		return string_from_wide(reg_value)
+		return unsafe { string_from_wide(reg_value) }
 	}
 	return error('not on windows')
 }
diff --git a/vlib/builtin/builtin_windows.c.v b/vlib/builtin/builtin_windows.c.v
index 9990278a06..127fdd3f26 100644
--- a/vlib/builtin/builtin_windows.c.v
+++ b/vlib/builtin/builtin_windows.c.v
@@ -142,14 +142,14 @@ fn print_backtrace_skipping_top_frames_msvc(skipframes int) bool {
 				nframe := frames - i - 1
 				mut lineinfo := ''
 				if C.SymGetLineFromAddr64(handle, frame_addr, &offset, &sline64) == 1 {
-					file_name := tos3(sline64.f_file_name)
+					file_name := unsafe { tos3(sline64.f_file_name) }
 					lnumber := sline64.f_line_number
 					lineinfo = '$file_name:$lnumber'
 				} else {
 					addr:
 					lineinfo = '?? : address = 0x${(&frame_addr):x}'
 				}
-				sfunc := tos3(fname)
+				sfunc := unsafe { tos3(fname) }
 				eprintln('${nframe:-2d}: ${sfunc:-25s}  $lineinfo')
 			} else {
 				// https://docs.microsoft.com/en-us/windows/win32/debug/system-error-codes
diff --git a/vlib/builtin/rune.v b/vlib/builtin/rune.v
index acfc66efcf..8cbb45acc8 100644
--- a/vlib/builtin/rune.v
+++ b/vlib/builtin/rune.v
@@ -51,6 +51,6 @@ pub fn (b []byte) bytestr() string {
 fn bytes2string(b []byte) string {
 	mut copy := b.clone()
 	copy << `\0`
-	res := tos(copy.data, copy.len-1)
+	res := unsafe { tos(copy.data, copy.len-1) }
 	return res
 }
diff --git a/vlib/builtin/string.v b/vlib/builtin/string.v
index 5687f7b222..7e2a14b77a 100644
--- a/vlib/builtin/string.v
+++ b/vlib/builtin/string.v
@@ -73,7 +73,7 @@ pub fn vstrlen(s byteptr) int {
 
 // tos converts a C string to a V string.
 // String data is reused, not copied.
-//[unsafe]
+[unsafe]
 pub fn tos(s byteptr, len int) string {
 	// This should never happen.
 	if s == 0 {
@@ -86,12 +86,14 @@ pub fn tos(s byteptr, len int) string {
 }
 
 // tos_clone returns a copy of `s`.
+[unsafe]
 pub fn tos_clone(s byteptr) string {
-	return tos2(s).clone()
+	return unsafe { tos2(s) }.clone()
 }
 
 // tos2 does the same as `tos`, but also calculates the length. Called by `string(bytes)` casts.
 // Used only internally.
+[unsafe]
 pub fn tos2(s byteptr) string {
 	if s == 0 {
 		panic('tos2: nil string')
@@ -103,6 +105,7 @@ pub fn tos2(s byteptr) string {
 }
 
 // tos3 does the same as `tos2`, but for char*, to avoid warnings.
+[unsafe]
 pub fn tos3(s charptr) string {
 	if s == 0 {
 		panic('tos3: nil string')
@@ -114,19 +117,21 @@ pub fn tos3(s charptr) string {
 }
 
 // tos4 does the same as `tos2`, but returns an empty string on nil ptr.
+[unsafe]
 pub fn tos4(s byteptr) string {
 	if s == 0 {
 		return ''
 	}
-	return tos2(s)
+	return unsafe { tos2(s) }
 }
 
 // tos5 does the same as `tos4`, but for char*, to avoid warnings.
+[unsafe]
 pub fn tos5(s charptr) string {
 	if s == 0 {
 		return ''
 	}
-	return tos3(s)
+	return unsafe { tos3(s) }
 }
 
 [deprecated]
@@ -207,7 +212,7 @@ pub fn (s string) cstr() byteptr {
 // cstring_to_vstring creates a copy of cstr and turns it into a v string.
 [unsafe]
 pub fn cstring_to_vstring(cstr byteptr) string {
-	return tos_clone(cstr)
+	return unsafe { tos_clone(cstr) }
 }
 
 // replace_once replaces the first occurence of `rep` with the string passed in `with`.
diff --git a/vlib/builtin/utf8.c.v b/vlib/builtin/utf8.c.v
index a6cc2e3896..8fb3c921a9 100644
--- a/vlib/builtin/utf8.c.v
+++ b/vlib/builtin/utf8.c.v
@@ -21,6 +21,7 @@ pub fn (_str string) to_wide() &u16 {
 	}
 }
 
+[unsafe]
 pub fn string_from_wide(_wstr &u16) string {
 	$if windows {
 		unsafe {
@@ -32,6 +33,7 @@ pub fn string_from_wide(_wstr &u16) string {
 	}
 }
 
+[unsafe]
 pub fn string_from_wide2(_wstr &u16, len int) string {
 	$if windows {
 		unsafe {
diff --git a/vlib/gg/gg.v b/vlib/gg/gg.v
index e049158bf0..75f15ba03a 100644
--- a/vlib/gg/gg.v
+++ b/vlib/gg/gg.v
@@ -249,7 +249,7 @@ fn gg_cleanup_fn(user_data voidptr) {
 
 fn gg_fail_fn(msg charptr, user_data voidptr) {
 	mut g := unsafe { &Context(user_data) }
-	vmsg := tos3(msg)
+	vmsg := unsafe { tos3(msg) }
 	if g.config.fail_fn != voidptr(0) {
 		g.config.fail_fn(vmsg, g.config.user_data)
 	} else {
diff --git a/vlib/json/json_primitives.v b/vlib/json/json_primitives.v
index b43dedda1e..9d83eb15cd 100644
--- a/vlib/json/json_primitives.v
+++ b/vlib/json/json_primitives.v
@@ -108,7 +108,7 @@ fn decode_string(root &C.cJSON) string {
 	}
 	// println('decode string valuestring="$root.valuestring"')
 	// return tos(root.valuestring, _strlen(root.valuestring))
-	return tos_clone(root.valuestring) // , _strlen(root.valuestring))
+	return unsafe { tos_clone(root.valuestring) } // , _strlen(root.valuestring))
 }
 
 fn C.cJSON_IsTrue(voidptr) bool
diff --git a/vlib/net/http/backend_nix.c.v b/vlib/net/http/backend_nix.c.v
index b580f5cbf3..cae10849de 100644
--- a/vlib/net/http/backend_nix.c.v
+++ b/vlib/net/http/backend_nix.c.v
@@ -45,17 +45,17 @@ fn (req &Request) ssl_do(port int, method Method, host_name string, path string)
 	mut readcounter := 0
 	for {
 		readcounter++
-		len := C.BIO_read(web, buff, bufsize)
+		len := unsafe { C.BIO_read(web, buff, bufsize) }
 		if len <= 0 {
 			break
 		}
 		$if debug_http ? {
 			eprintln('ssl_do, read ${readcounter:4d} | len: $len')
 			eprintln('-'.repeat(20))
-			eprintln(tos(buff, len))
+			eprintln(unsafe { tos(buff, len) })
 			eprintln('-'.repeat(20))
 		}
-		content.write_bytes(buff, len)
+		unsafe { content.write_bytes(buff, len) }
 	}
 	if web != 0 {
 		C.BIO_free_all(web)
diff --git a/vlib/net/tcp_read_line.v b/vlib/net/tcp_read_line.v
index cd78953e50..38cbdeb199 100644
--- a/vlib/net/tcp_read_line.v
+++ b/vlib/net/tcp_read_line.v
@@ -35,7 +35,7 @@ pub fn (mut con TcpConn) read_line() string {
 			}
 		}
 		bufbp := byteptr(buf)
-		line = tos_clone(bufbp)
+		line = unsafe { tos_clone(bufbp) }
 		if eol_idx > 0 {
 			// At this point, we are sure that recv returned valid data,
 			// that contains *at least* one line.
diff --git a/vlib/os/environment.c.v b/vlib/os/environment.c.v
index 705833b653..ff7173ab42 100644
--- a/vlib/os/environment.c.v
+++ b/vlib/os/environment.c.v
@@ -72,7 +72,7 @@ pub fn environ() map[string]string {
 		mut estrings := C.GetEnvironmentStringsW()
 		mut eline := ''
 		for c := estrings; *c != 0; {
-			eline = string_from_wide(c)
+			eline = unsafe { string_from_wide(c) }
 			eq_index := eline.index_byte(`=`)
 			if eq_index > 0 {
 				res[eline[0..eq_index]] = eline[eq_index + 1..]
diff --git a/vlib/os/os_c.v b/vlib/os/os_c.v
index 31616091e3..eed279db1e 100644
--- a/vlib/os/os_c.v
+++ b/vlib/os/os_c.v
@@ -319,7 +319,7 @@ pub fn posix_get_error_msg(code int) string {
 	if ptr_text == 0 {
 		return ''
 	}
-	return tos3(ptr_text)
+	return unsafe { tos3(ptr_text) }
 }
 
 // vpclose will close a file pointer opened with `vpopen`.
@@ -463,7 +463,7 @@ pub fn rmdir(path string) ? {
 // print_c_errno will print the current value of `C.errno`.
 fn print_c_errno() {
 	e := C.errno
-	se := tos_clone(byteptr(C.strerror(C.errno)))
+	se := unsafe { tos_clone(byteptr(C.strerror(C.errno))) }
 	println('errno=$e err=$se')
 }
 
@@ -498,12 +498,12 @@ pub fn get_raw_line() string {
 	} $else {
 		max := size_t(0)
 		mut buf := charptr(0)
-		nr_chars := C.getline(&buf, &max, C.stdin)
+		nr_chars := unsafe { C.getline(&buf, &max, C.stdin) }
 		// defer { unsafe{ free(buf) } }
 		if nr_chars == 0 || nr_chars == -1 {
 			return ''
 		}
-		return tos3(buf)
+		return unsafe { tos3(buf) }
 		// res := tos_clone(buf)
 		// return res
 	}
@@ -610,7 +610,7 @@ pub fn executable() string {
 				// https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfinalpathnamebyhandlew
 				final_len := C.GetFinalPathNameByHandleW(file, final_path, size, 0)
 				if final_len < size {
-					ret := string_from_wide2(final_path, final_len)
+					ret := unsafe { string_from_wide2(final_path, final_len) }
 					// remove '\\?\' from beginning (see link above)
 					return ret[4..]
 				} else {
@@ -619,7 +619,7 @@ pub fn executable() string {
 			}
 			C.CloseHandle(file)
 		}
-		return string_from_wide2(result, len)
+		return unsafe { string_from_wide2(result, len) }
 	}
 	$if macos {
 		mut result := vcalloc(max_path_len)
diff --git a/vlib/os/os_nix.c.v b/vlib/os/os_nix.c.v
index fde3160424..7aa500b3ed 100644
--- a/vlib/os/os_nix.c.v
+++ b/vlib/os/os_nix.c.v
@@ -82,7 +82,7 @@ fn init_os_args(argc int, argv &&byte) []string {
 
 pub fn ls(path string) ?[]string {
 	mut res := []string{}
-	dir := C.opendir(charptr(path.str))
+	dir := unsafe { C.opendir(charptr(path.str)) }
 	if isnil(dir) {
 		return error('ls() couldnt open dir "$path"')
 	}
@@ -99,8 +99,8 @@ pub fn ls(path string) ?[]string {
 				|| (bptr[0] == `.` && bptr[1] == `.` && bptr[2] == 0) {
 				continue
 			}
+			res << tos_clone(bptr)
 		}
-		res << tos_clone(bptr)
 	}
 	C.closedir(dir)
 	return res
diff --git a/vlib/os/os_windows.c.v b/vlib/os/os_windows.c.v
index 8017dac138..ad7d119565 100644
--- a/vlib/os/os_windows.c.v
+++ b/vlib/os/os_windows.c.v
@@ -79,7 +79,7 @@ mut:
 fn init_os_args_wide(argc int, argv &byteptr) []string {
 	mut args_ := []string{}
 	for i in 0 .. argc {
-		args_ << string_from_wide(unsafe { &u16(argv[i]) })
+		args_ << unsafe { string_from_wide(&u16(argv[i])) }
 	}
 	return args_
 }
@@ -102,12 +102,12 @@ pub fn ls(path string) ?[]string {
 	// NOTE:TODO: once we have a way to convert utf16 wide character to utf8
 	// we should use FindFirstFileW and FindNextFileW
 	h_find_files := C.FindFirstFile(path_files.to_wide(), voidptr(&find_file_data))
-	first_filename := string_from_wide(&u16(find_file_data.c_file_name))
+	first_filename := unsafe { string_from_wide(&u16(find_file_data.c_file_name)) }
 	if first_filename != '.' && first_filename != '..' {
 		dir_files << first_filename
 	}
 	for C.FindNextFile(h_find_files, voidptr(&find_file_data)) > 0 {
-		filename := string_from_wide(&u16(find_file_data.c_file_name))
+		filename := unsafe { string_from_wide(&u16(find_file_data.c_file_name)) }
 		if filename != '.' && filename != '..' {
 			dir_files << filename.clone()
 		}
@@ -218,7 +218,7 @@ pub fn get_error_msg(code int) string {
 	if ptr_text == 0 { // compare with null
 		return ''
 	}
-	return string_from_wide(ptr_text)
+	return unsafe { string_from_wide(ptr_text) }
 }
 
 // exec starts the specified command, waits for it to complete, and returns its output.
@@ -273,15 +273,17 @@ pub fn exec(cmd string) ?Result {
 	mut bytes_read := u32(0)
 	mut read_data := strings.new_builder(1024)
 	for {
-		readfile_result := C.ReadFile(child_stdout_read, buf, 1000, voidptr(&bytes_read),
-			0)
-		read_data.write_bytes(buf, int(bytes_read))
-		if readfile_result == false || int(bytes_read) == 0 {
+		mut result := false
+		unsafe {
+			result = C.ReadFile(child_stdout_read, buf, 1000, voidptr(&bytes_read), 0)
+			read_data.write_bytes(buf, int(bytes_read))
+		}
+		if result == false || int(bytes_read) == 0 {
 			break
 		}
 	}
 	soutput := read_data.str().trim_space()
-	read_data.free()
+	unsafe { read_data.free() }
 	exit_code := u32(0)
 	C.WaitForSingleObject(proc_info.h_process, C.INFINITE)
 	C.GetExitCodeProcess(proc_info.h_process, voidptr(&exit_code))
diff --git a/vlib/picoev/picoev.v b/vlib/picoev/picoev.v
index 07ba1b9ce8..6b7825dbd2 100644
--- a/vlib/picoev/picoev.v
+++ b/vlib/picoev/picoev.v
@@ -170,7 +170,7 @@ fn rw_callback(loop &C.picoev_loop, fd int, events int, cb_arg voidptr) {
 			}
 		} else {
 			r += idx
-			mut s := tos(buf, r)
+			mut s := unsafe { tos(buf, r) }
 			mut out := p.out
 			unsafe {
 				out += fd * max_write
diff --git a/vlib/picohttpparser/request.v b/vlib/picohttpparser/request.v
index 9d8a182dd5..573cfd3076 100644
--- a/vlib/picohttpparser/request.v
+++ b/vlib/picohttpparser/request.v
@@ -28,8 +28,10 @@ pub fn (mut r Request) parse_request(s string, max_headers int) int {
 		0
 	)
 	if pret > 0 {
-		r.method = tos(r.method.str, int(method_len))
-		r.path = tos(r.path.str, int(path_len))
+		unsafe {
+			r.method = tos(r.method.str, int(method_len))
+			r.path = tos(r.path.str, int(path_len))
+		}
 		r.num_headers = num_headers
 	}
 	return pret
@@ -46,8 +48,10 @@ pub fn (mut r Request) parse_request_path(s string) int {
 		&r.path, &path_len
 	)
 	if pret > 0 {
-		r.method = tos(r.method.str, int(method_len))
-		r.path = tos(r.path.str, int(path_len))
+		unsafe {
+			r.method = tos(r.method.str, int(method_len))
+			r.path = tos(r.path.str, int(path_len))
+		}
 	}
 	return pret
 }
@@ -63,8 +67,10 @@ pub fn (mut r Request) parse_request_path_pipeline(s string) int {
 		&r.path, &path_len
 	)
 	if pret > 0 {
-		r.method = tos(r.method.str, int(method_len))
-		r.path = tos(r.path.str, int(path_len))
+		unsafe {
+			r.method = tos(r.method.str, int(method_len))
+			r.path = tos(r.path.str, int(path_len))
+		}
 	}
 	return pret
 }
diff --git a/vlib/regex/regex.v b/vlib/regex/regex.v
index aec86d71e0..dfaca4a9af 100644
--- a/vlib/regex/regex.v
+++ b/vlib/regex/regex.v
@@ -530,7 +530,7 @@ fn (re RE) get_char_class(pc int) string {
 		buf_ptr[i] = byte(0)
 	}
 
-	return tos_clone( buf_ptr )
+	return unsafe { tos_clone( buf_ptr ) }
 }
 
 fn (re RE) check_char_class(pc int, ch rune) bool {
diff --git a/vlib/sqlite/sqlite.v b/vlib/sqlite/sqlite.v
index f7a6139a22..2ed929011a 100644
--- a/vlib/sqlite/sqlite.v
+++ b/vlib/sqlite/sqlite.v
@@ -123,7 +123,7 @@ pub fn (db DB) q_string(query string) string {
 	stmt := &C.sqlite3_stmt(0)
 	C.sqlite3_prepare_v2(db.conn, query.str, -1, &stmt, 0)
 	C.sqlite3_step(stmt)
-	res := tos_clone(C.sqlite3_column_text(stmt, 0))
+	res := unsafe { tos_clone(C.sqlite3_column_text(stmt, 0)) }
 	C.sqlite3_finalize(stmt)
 	return res
 }
@@ -145,7 +145,7 @@ pub fn (db DB) exec(query string) ([]Row, int) {
 		}
 		mut row := Row{}
 		for i in 0 .. nr_cols {
-			val := tos_clone(C.sqlite3_column_text(stmt, i))
+			val := unsafe { tos_clone(C.sqlite3_column_text(stmt, i)) }
 			row.vals << val
 		}
 		rows << row
diff --git a/vlib/strconv/format.v b/vlib/strconv/format.v
index ba16e87818..d76ec93b24 100644
--- a/vlib/strconv/format.v
+++ b/vlib/strconv/format.v
@@ -183,7 +183,7 @@ pub fn f64_to_str_lnd(f f64, dec_digit int) string {
 		}
 		res[r_i] = 0
 		//println("result: [${tos(&res[0],r_i)}]")
-		return tos(res.data, r_i)
+		return unsafe { tos(res.data, r_i) }
 	} else {
 		if dec_digit > 0 {
 			mut c := 0
@@ -194,7 +194,7 @@ pub fn f64_to_str_lnd(f f64, dec_digit int) string {
 			}
 			res[r_i] = 0
 		}
-		return tos(res.data, r_i)
+		return unsafe { tos(res.data, r_i) }
 	}
 }
 
diff --git a/vlib/strconv/utilities.v b/vlib/strconv/utilities.v
index 048635afdb..d9d24d8a74 100644
--- a/vlib/strconv/utilities.v
+++ b/vlib/strconv/utilities.v
@@ -336,5 +336,5 @@ pub fn f64_to_str_l(f f64) string {
 		}
 	}
 	res[r_i] = 0
-	return tos(res.data,r_i)
+	return unsafe { tos(res.data,r_i) }
 }
diff --git a/vlib/strings/builder.v b/vlib/strings/builder.v
index ce4b6d3acc..dbf0313c61 100644
--- a/vlib/strings/builder.v
+++ b/vlib/strings/builder.v
@@ -27,6 +27,7 @@ pub fn new_builder(initial_size int) Builder {
 }
 
 // write_bytes appends `bytes` to the accumulated buffer
+[unsafe]
 pub fn (mut b Builder) write_bytes(bytes byteptr, howmany int) {
 	b.buf.push_many(bytes, howmany)
 	b.len += howmany
@@ -61,8 +62,7 @@ pub fn (mut b Builder) go_back(n int) {
 fn bytes2string(b []byte) string {
 	mut copy := b.clone()
 	copy << byte(`\0`)
-	res := tos(copy.data, copy.len - 1)
-	return res
+	return unsafe { tos(copy.data, copy.len - 1) }
 }
 
 // cut_last cuts the last `n` bytes from the buffer and returns them
@@ -137,6 +137,7 @@ pub fn (mut b Builder) str() string {
 }
 
 // free - manually free the contents of the buffer
+[unsafe]
 pub fn (mut b Builder) free() {
 	unsafe { free(b.buf.data) }
 	// b.buf = []byte{cap: b.initial_size}
diff --git a/vlib/v/util/util.v b/vlib/v/util/util.v
index 07c46ef869..9943edcf00 100644
--- a/vlib/v/util/util.v
+++ b/vlib/v/util/util.v
@@ -29,8 +29,10 @@ pub const (
 pub fn vhash() string {
 	mut buf := [50]byte{}
 	buf[0] = 0
-	unsafe { C.snprintf(charptr(buf), 50, '%s', C.V_COMMIT_HASH) }
-	return tos_clone(buf)
+	unsafe {
+		C.snprintf(charptr(buf), 50, '%s', C.V_COMMIT_HASH)
+		return tos_clone(buf)
+	}
 }
 
 pub fn full_hash() string {
@@ -95,8 +97,10 @@ pub fn githash(should_get_from_filesystem bool) string {
 	}
 	mut buf := [50]byte{}
 	buf[0] = 0
-	unsafe { C.snprintf(charptr(buf), 50, '%s', C.V_CURRENT_COMMIT_HASH) }
-	return tos_clone(buf)
+	unsafe {
+		C.snprintf(charptr(buf), 50, '%s', C.V_CURRENT_COMMIT_HASH)
+		return tos_clone(buf)
+	}
 }
 
 //
diff --git a/vlib/vweb/vweb.v b/vlib/vweb/vweb.v
index 98708669c2..5cd81677e6 100644
--- a/vlib/vweb/vweb.v
+++ b/vlib/vweb/vweb.v
@@ -96,7 +96,7 @@ pub fn (mut ctx Context) send_response_to_client(mimetype string, res string) bo
 	ctx.done = true
 	mut sb := strings.new_builder(1024)
 	defer {
-		sb.free()
+		unsafe { sb.free() }
 	}
 	sb.write('HTTP/1.1 $ctx.status')
 	sb.write('\r\nContent-Type: $mimetype')
diff --git a/vlib/x/websocket/handshake.v b/vlib/x/websocket/handshake.v
index e285124cd4..518ff2f39f 100644
--- a/vlib/x/websocket/handshake.v
+++ b/vlib/x/websocket/handshake.v
@@ -10,7 +10,7 @@ fn (mut ws Client) handshake() ? {
 	seckey := base64.encode(nonce)
 	mut sb := strings.new_builder(1024)
 	defer {
-		sb.free()
+		unsafe { sb.free() }
 	}
 	sb.write('GET ')
 	sb.write(ws.uri.resource)
diff --git a/vlib/x/websocket/utils.v b/vlib/x/websocket/utils.v
index 97e201b879..ed26db6894 100644
--- a/vlib/x/websocket/utils.v
+++ b/vlib/x/websocket/utils.v
@@ -35,7 +35,7 @@ fn create_key_challenge_response(seckey string) ?string {
 	sha1buf := seckey + guid
 	shabytes := sha1buf.bytes()
 	hash := sha1.sum(shabytes)
-	b64 := base64.encode(tos(hash.data, hash.len))
+	b64 := base64.encode(unsafe { tos(hash.data, hash.len) })
 	unsafe {
 		hash.free()
 		shabytes.free()
@@ -50,5 +50,5 @@ fn get_nonce(nonce_size int) string {
 	for i in 0 .. nonce_size {
 		nonce[i] = alphanum[rand.intn(alphanum.len)]
 	}
-	return tos(nonce.data, nonce.len).clone()
+	return unsafe { tos(nonce.data, nonce.len) }.clone()
 }