[patch] Backport memory leak fix to 7.1

[Sami Wagiaalla]

> Tom> I think it is fine to put these on the 7.1 branch, pending , but for
> 
> Oops, bad edit ... I was going to write "pending resolution of the issue
> Ulrich just raised", but then I saw the rest of the thread and forgot to
> either finish the clause or delete it.

Is this okay to go into the gdb_7_1-branch ?
The issue Ulrich raised was resolved by marking the tests are known
failures; that version of the compiler provides incorrect debuginfo.