To make the gcprog for global data containing variables of types defined in other shared
libraries, we need to know a lot about those types. So read the value of any symbol with
a name starting with "type.". If a type uses a mask, the name of the symbol defining the
mask unfortunately cannot be predicted from the type name so I have to keep track of the
addresses of every such symbol and associate them with the type symbols after the fact.

I'm not very happy about this change, but something like this is needed and this is as
pleasant as I know how to make it.

Change-Id: I408d831b08b3b31e0610688c41367b23998e975c
Reviewed-on: https://go-review.googlesource.com/8334Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>