tree bed004a1cdfce7afafb256cbd44bb621ba9b350e
parent 08cd8842f1937d1f81f7c558bfbabb0e58836513
author Joe Tsai <joetsai@digital-static.net> 1553030069 -0700
committer Joe Tsai <thebrokentoaster@gmail.com> 1553039289 +0000

internal/legacy: guarantee one-to-one generation of wrapper types

When concurrent requests to wrap a type occurs, it is possible that
two different descriptors are created for the same Go type.
Add sufficient synchronization to ensure that one descriptor is ever
returned for one Go type.

Change-Id: Idbbca4c1877a70317b39900ae83bfc3085d4a9c5
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/168398
Reviewed-by: Herbie Ong <herbie@google.com>