[clang] [Clang] Skip past code generation for unevaluated lambdas (PR #124572)

[Erich Keane via cfe-commits]

erichkeane wrote:

> > I would expect that we should instead be marking this function not `isUsed` (or `isReferenced`? ) to determine whether this should be emitted, and I would expect that to get caught in our existing infrastructure for that.
> 
> And we do. But mangling happens before we make that decision cf stacktrace here [#82926 (comment)](https://github.com/llvm/llvm-project/issues/82926#issuecomment-1963388189)

Which call in EmitGlobal is the one that calls it?  I would expect that either of the two (not hte annotations one for obvious reasons) should be able to filter it THERE instead.  Do we perhaps just mangle 'too early'?



https://github.com/llvm/llvm-project/pull/124572