[llvm] r290020 - Add support for formatv to llvm::Twine.

[Joerg Sonnenberger via llvm-commits]

On Sat, Dec 17, 2016 at 12:38:15AM -0000, Zachary Turner via llvm-commits wrote:
> Author: zturner
> Date: Fri Dec 16 18:38:15 2016
> New Revision: 290020
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=290020&view=rev
> Log:
> Add support for formatv to llvm::Twine.

Isn't this going to call formatv more than once if the Twine is
evaluated multiple times? It feels like this partially defeats the
purpose of the Twine in first place. Is there a good reason why formatv
can't provide its own SmallString buffer for such use?

Joerg