[go] math/rand/v2: document PCG and ChaCha8 tradeoffs

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Jun 9, 2026, 10:10:42 PM (7 hours ago) Jun 9

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math/rand/v2: document PCG and ChaCha8 tradeoffs

Document that PCG is the fast general-purpose source and ChaCha8 trades speed for stronger resistance to prediction.

Fixes #79891

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Change-Id: Ic4133dd9bd860c2643c622f799f2c54b1678e4f0

GitHub-Last-Rev: 45f06afd4481b8b9dcd4c9822733dd30de7b18ac

GitHub-Pull-Request: golang/go#79926

Change diff

diff --git a/src/math/rand/v2/rand.go b/src/math/rand/v2/rand.go
index f6b2e47..19af211 100644
--- a/src/math/rand/v2/rand.go
+++ b/src/math/rand/v2/rand.go
@@ -12,6 +12,9 @@
 // Top-level functions, such as [Float64] and [Int],
 // are safe for concurrent use by multiple goroutines.
 //
+// The [PCG] source is a fast general-purpose pseudo-random generator.
+// The [ChaCha8] source trades speed for stronger resistance to prediction.
+//
 // This package's outputs might be easily predictable regardless of how it's
 // seeded. For random numbers suitable for security-sensitive work, see the
 // [crypto/rand] package.

Change information

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M src/math/rand/v2/rand.go

Change size: XS

Delta: 1 file changed, 3 insertions(+), 0 deletions(-)

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Jun 9, 2026, 10:52:23 PM (7 hours ago) Jun 9

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Attention needed from Robert Griesemer and Russ Cox

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Gerrit Bot uploaded patch set #2 to this change.

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