tests: fix compilation of the semaphore_wait.v program with latest V

Author: spytheman

cmd/tools/vtest-all.v

@@ -294,6 +294,11 @@ fn get_all_commands() []Command {
 		rmfile: 'vtmp_unused'
 	}
 	$if linux {
+		res << Command{
+			line:   '${vexe} -o swait vlib/v/tests/reliability/semaphore_wait.v'
+			okmsg:  'V can compile semaphore_wait.v on Linux with GC on.'
+			rmfile: 'swait'
+		}
 		res << Command{
 			line:   '${vexe} -cc gcc -keepc -freestanding -o bel vlib/os/bare/bare_example_linux.v'
 			okmsg:  'V can compile with -freestanding on Linux with GCC.'

vlib/v/tests/reliability/semaphore_wait.v

@@ -46,23 +46,23 @@ const log2n = 9
 const n = 1 << log2n
 const n4 = f64(u64(1) << (4 * log2n))
 
-fn waste_mem() {
+fn waste_mem() ! {
 	mut objs := PtrPtrObj{
-		nxt: []&PtrObj{len: n}
+		nxt: unsafe { []&PtrObj{len: n} }
 	}
 	for {
-		sz := rand.int_in_range(10, 1000)
+		sz := rand.int_in_range(10, 1000)!
 		mut new_obj := &PtrObj{
-			nxt: []&DataObj{len: sz}
+			nxt: unsafe { []&DataObj{len: sz} }
 		}
-		sz2 := rand.int_in_range(10, 500000)
+		sz2 := rand.int_in_range(10, 500000)!
 		new_obj2 := &DataObj{
 			data: []f64{len: sz2}
 		}
-		idx2 := rand.int_in_range(0, sz)
+		idx2 := rand.int_in_range(0, sz)!
 		new_obj.nxt[idx2] = new_obj2
 		// non-equally distributed random index
-		idx := int(math.sqrt(math.sqrt(rand.f64n(n4))))
+		idx := int(math.sqrt(math.sqrt(rand.f64n(n4)!)))
 		objs.nxt[idx] = new_obj
 	}
 }