time,hash,rand: tag more functions with an explicit @[ignore_overflow] or with explicit casts (where needed)

Author: spytheman

vlib/hash/wyhash.v

@@ -21,13 +21,13 @@ const wyp2 = u64(0x8ebc6af09c88c6e3)
 const wyp3 = u64(0x589965cc75374cc3)
 const wyp4 = u64(0x1d8e4e27c47d124f)
 
-@[inline]
+@[ignore_overflow; inline]
 fn wyrotr(v u64, k u32) u64 {
 	return (v >> k) | (v << (64 - k))
 }
 
 // wymum returns a hash by performing multiply and mix on `a` and `b`.
-@[inline]
+@[ignore_overflow; inline]
 pub fn wymum(a u64, b u64) u64 {
 	/*
 	mut r := u128(a)

vlib/rand/mt19937/mt19937.v

@@ -72,6 +72,7 @@ fn get_first_state(seed_data []u32) []u64 {
 }
 
 // calculate_state returns a random state array calculated from the `seed_data`.
+@[ignore_overflow]
 fn calculate_state(seed_data []u32, mut state []u64) []u64 {
 	lo := u64(seed_data[0])
 	hi := u64(seed_data[1])
@@ -145,7 +146,7 @@ pub fn (mut rng MT19937RNG) u32() u32 {
 const mag01 = [u64(0), u64(matrix_a)]
 
 // u64 returns a pseudorandom 64bit int in range `[0, 2⁶⁴)`.
-@[direct_array_access; inline]
+@[direct_array_access; ignore_overflow; inline]
 pub fn (mut rng MT19937RNG) u64() u64 {
 	mut x := u64(0)
 	mut i := int(0)

vlib/rand/musl/musl_rng.v

@@ -70,6 +70,7 @@ fn temper(prev u32) u32 {
 }
 
 // u32 returns a pseudorandom 32-bit unsigned integer (`u32`).
+@[ignore_overflow]
 pub fn (mut rng MuslRNG) u32() u32 {
 	rng.state = rng.state * 1103515245 + 12345
 	// We are not dividing by 2 (or shifting right by 1)

vlib/rand/pcg32/pcg32.v

@@ -21,6 +21,7 @@ mut:
 // seed seeds the PCG32RNG with 4 `u32` values.
 // The first 2 represent the 64-bit initial state as `[lower 32 bits, higher 32 bits]`
 // The last 2 represent the 64-bit stream/step of the PRNG.
+@[ignore_overflow]
 pub fn (mut rng PCG32RNG) seed(seed_data []u32) {
 	if seed_data.len != 4 {
 		eprintln('PCG32RNG needs 4 u32s to be seeded. First two the initial state and the last two the stream/step. Both in little endian format: [lower, higher].')
@@ -69,7 +70,7 @@ pub fn (mut rng PCG32RNG) u16() u16 {
 }
 
 // u32 returns a pseudorandom unsigned `u32`.
-@[inline]
+@[ignore_overflow; inline]
 pub fn (mut rng PCG32RNG) u32() u32 {
 	oldstate := rng.state
 	rng.state = oldstate * (6364136223846793005) + rng.inc

vlib/rand/rand.c.v

@@ -82,6 +82,7 @@ pub fn new_uuid_v7_session() UUIDSession {
 }
 
 // next get a new uuid_v7 from current session.
+@[ignore_overflow]
 pub fn (mut u UUIDSession) next() string {
 	timestamp := u64(time.now().unix_nano())
 	// make place for holding 4 bits `version`

vlib/rand/seed/seed.v

@@ -6,7 +6,7 @@ module seed
 import time
 
 // nr_next returns a next value based on the previous value `prev`.
-@[inline]
+@[ignore_overflow; inline]
 fn nr_next(prev u32) u32 {
 	return prev * 1664525 + 1013904223
 }

vlib/rand/splitmix64/splitmix64.v

@@ -75,7 +75,7 @@ pub fn (mut rng SplitMix64RNG) u32() u32 {
 }
 
 // u64 returns a pseudorandom 64bit int in range `[0, 2⁶⁴)`.
-@[inline]
+@[ignore_overflow; inline]
 pub fn (mut rng SplitMix64RNG) u64() u64 {
 	rng.state += (0x9e3779b97f4a7c15)
 	mut z := rng.state

vlib/rand/wyrand/wyrand.v

@@ -82,7 +82,7 @@ pub fn (mut rng WyRandRNG) u32() u32 {
 }
 
 // u64 returns a pseudorandom 64bit int in range `[0, 2⁶⁴)`.
-@[inline]
+@[ignore_overflow; inline]
 pub fn (mut rng WyRandRNG) u64() u64 {
 	unsafe {
 		mut seed1 := rng.state

vlib/rand/xoroshiro128pp/xoros128pp.v

@@ -83,7 +83,7 @@ pub fn (mut rng XOROS128PPRNG) u32() u32 {
 }
 
 // u64 returns a pseudorandom 64-bit unsigned `u64`.
-@[inline]
+@[ignore_overflow; inline]
 pub fn (mut rng XOROS128PPRNG) u64() u64 {
 	oldstate0 := rng.state0
 	mut oldstate1 := rng.state1

vlib/time/operator_test.v

@@ -371,7 +371,7 @@ fn test_time2_copied_from_time1_should_be_equal() {
 fn test_subtract() {
 	d_seconds := 3
 	d_nanoseconds := 13
-	duration := d_seconds * second + d_nanoseconds * nanosecond
+	duration := i64(d_seconds) * second + d_nanoseconds * nanosecond
 	t1 := new(Time{
 		year:       2000
 		month:      5