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to avoid others running in same problem, where the buffer was overwritten with null values

transform/transform.go

@@ -6,6 +6,7 @@
 // bytes passing through as well as various transformations. Example
 // transformations provided by other packages include normalization and
 // conversion between character sets.
+// It is not recommended to use the package from multiple go routines
 package transform // import "golang.org/x/text/transform"
 
 import (