runtime: seed fastrand() with current time

tinygo-org · Sep 25, 2024 · dabcb16 · dabcb16
1 parent a26502c
commit dabcb16
Showing 1 changed file with 7 additions and 2 deletions.
diff --git a/src/runtime/algorithm.go b/src/runtime/algorithm.go
@@ -23,7 +23,12 @@ func fastrand() uint32 {
 	return xorshift32State
 }
 
-var xorshift32State uint32 = 1
+func init() {
+	xorshift64State = uint64(nanotime() | 1) // protect against nanotime() returning 0
+	xorshift32State = uint32(xorshift64State)
+}
+
+var xorshift32State uint32
 
 func xorshift32(x uint32) uint32 {
 	// Algorithm "xor" from p. 4 of Marsaglia, "Xorshift RNGs".
@@ -43,7 +48,7 @@ func fastrand64() uint64 {
 	return xorshift64State
 }
 
-var xorshift64State uint64 = 1
+var xorshift64State uint64
 
 // 64-bit xorshift multiply rng from http://vigna.di.unimi.it/ftp/papers/xorshift.pdf
 func xorshiftMult64(x uint64) uint64 {