math/rand: mention that the default Source is thread-safe

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/11709043

diff --git a/src/pkg/math/rand/rand.go b/src/pkg/math/rand/rand.go
index 608012a300d21cb4dfd0fd7f8b23d83a64bd70ff..2157cdb46581ca6c40bad5a185dbd283cee59878 100644 (file)
--- a/src/pkg/math/rand/rand.go
+++ b/src/pkg/math/rand/rand.go
@@ -8,6 +8,7 @@
 // Float64 and Int, use a default shared Source that produces a deterministic
 // sequence of values each time a program is run. Use the Seed function to
 // initialize the default Source if different behavior is required for each run.
+// The default Source is safe for concurrent use by multiple goroutines.
 package rand
 
 import "sync"