The -msan option compiles Go code to use the memory sanitizer.  This is
intended for use when linking with C/C++ code compiled with
-fsanitize=memory.  When memory blocks are passed back and forth between
C/C++ and Go, code in both languages will agree as to whether the memory
is correctly initialized or not, and will report errors for any use of
uninitialized memory.

Change-Id: I2dbdbd26951eacb7d84063cfc7297f88ffadd70c
Reviewed-on: https://go-review.googlesource.com/16169Reviewed-by: David Crawshaw <crawshaw@golang.org>