vlib: replace all `goto` statements with labelled break (#8531)

vlib/encoding/utf8/utf8.v

@@ -32,7 +32,6 @@ fn (mut s Utf8State) seq(r0 bool, r1 bool, is_tail bool) bool {
 			s.subindex++
 			return true
 		}
-		goto next
 	} else {
 		s.failed = true
 		if is_tail {
@@ -42,7 +41,6 @@ fn (mut s Utf8State) seq(r0 bool, r1 bool, is_tail bool) bool {
 		}
 		return true
 	}
-	next:
 	s.index++
 	s.subindex = 0
 	return false

vlib/sync/channels.v

@@ -563,6 +563,7 @@ pub fn channel_select(mut channels []&Channel, dir []Direction, mut objrefs []vo
 	}
 	stopwatch := if timeout <= 0 { time.StopWatch{} } else { time.new_stopwatch({}) }
 	mut event_idx := -1 // negative index means `timed out`
+outer:
 	for {
 		rnd := rand.u32_in_range(0, u32(channels.len))
 		mut num_closed := 0
@@ -575,7 +576,7 @@ pub fn channel_select(mut channels []&Channel, dir []Direction, mut objrefs []vo
 				stat := channels[i].try_push_priv(objrefs[i], true)
 				if stat == .success {
 					event_idx = i
-					goto restore
+					break outer
 				} else if stat == .closed {
 					num_closed++
 				}
@@ -583,7 +584,7 @@ pub fn channel_select(mut channels []&Channel, dir []Direction, mut objrefs []vo
 				stat := channels[i].try_pop_priv(objrefs[i], true)
 				if stat == .success {
 					event_idx = i
-					goto restore
+					break outer
 				} else if stat == .closed {
 					num_closed++
 				}
@@ -591,21 +592,20 @@ pub fn channel_select(mut channels []&Channel, dir []Direction, mut objrefs []vo
 		}
 		if num_closed == channels.len {
 			event_idx = -2
-			goto restore
+			break outer
 		}
 		if timeout == 0 {
-			goto restore
+			break outer
 		}
 		if timeout > 0 {
 			remaining := timeout - stopwatch.elapsed()
 			if !sem.timed_wait(remaining) {
-				goto restore
+				break outer
 			}
 		} else {
 			sem.wait()
 		}
 	}
-restore:
 	// reset subscribers
 	for i, ch in channels {
 		if dir[i] == .push {

vlib/sync/sync_macos.c.v

@@ -149,6 +149,7 @@ pub fn (mut sem Semaphore) wait() {
 	}
 	C.pthread_mutex_lock(&sem.mtx)
 	c = C.atomic_load_u32(&sem.count)
+outer:
 	for {
 		if c == 0 {
 			C.pthread_cond_wait(&sem.cond, &sem.mtx)
@@ -159,11 +160,10 @@ pub fn (mut sem Semaphore) wait() {
 				if c > 1 {
 					C.pthread_cond_signal(&sem.cond)
 				}
-				goto unlock
+				break outer
 			}
 		}
 	}
-unlock:
 	C.pthread_mutex_unlock(&sem.mtx)
 }
 
@@ -184,11 +184,12 @@ pub fn (mut sem Semaphore) timed_wait(timeout time.Duration) bool {
 	t_spec := timeout.timespec()
 	mut res := 0
 	c = C.atomic_load_u32(&sem.count)
+outer:
 	for {
 		if c == 0 {
 			res = C.pthread_cond_timedwait(&sem.cond, &sem.mtx, &t_spec)
 			if res == C.ETIMEDOUT {
-				goto unlock
+				break outer
 			}
 			c = C.atomic_load_u32(&sem.count)
 		}
@@ -197,11 +198,10 @@ pub fn (mut sem Semaphore) timed_wait(timeout time.Duration) bool {
 				if c > 1 {
 					C.pthread_cond_signal(&sem.cond)
 				}
-				goto unlock
+				break outer
 			}
 		}
 	}
-unlock:
 	C.pthread_mutex_unlock(&sem.mtx)
 	return res == 0
 }

vlib/sync/sync_windows.c.v

@@ -125,6 +125,7 @@ pub fn (mut sem Semaphore) wait() {
 	}
 	C.AcquireSRWLockExclusive(&sem.mtx)
 	c = C.atomic_load_u32(&sem.count)
+outer:
 	for {
 		if c == 0 {
 			C.SleepConditionVariableSRW(&sem.cond, &sem.mtx, C.INFINITE, 0)
@@ -135,11 +136,10 @@ pub fn (mut sem Semaphore) wait() {
 				if c > 1 {
 					C.WakeConditionVariable(&sem.cond)
 				}
-				goto unlock
+				break outer
 			}
 		}
 	}
-unlock:
 	C.ReleaseSRWLockExclusive(&sem.mtx)
 }
 
@@ -160,11 +160,12 @@ pub fn (mut sem Semaphore) timed_wait(timeout time.Duration) bool {
 	t_ms := u32(timeout / time.millisecond)
 	mut res := 0
 	c = C.atomic_load_u32(&sem.count)
+outer:
 	for {
 		if c == 0 {
 			res = C.SleepConditionVariableSRW(&sem.cond, &sem.mtx, t_ms, 0)
 			if res == 0 {
-				goto unlock
+				break outer
 			}
 			c = C.atomic_load_u32(&sem.count)
 		}
@@ -173,11 +174,10 @@ pub fn (mut sem Semaphore) timed_wait(timeout time.Duration) bool {
 				if c > 1 {
 					C.WakeConditionVariable(&sem.cond)
 				}
-				goto unlock
+				break outer
 			}
 		}
 	}
-unlock:
 	C.ReleaseSRWLockExclusive(&sem.mtx)
 	return res != 0
 }