Hi,

How's the integration of DWARF support coming along? It's probably one of the most important improvements to the runtime in quite some time since unlocks *two* important features, namely

 * trustworthy profiling (using e.g. Linux perf events and other low-overhead, code preserving, sampling profilers), and
 * stack traces.

The former is really important to move our core libraries performance up a notch. Right now -prof is too invasive for it to be useful when evaluating the hotspots in these libraries (which are already often heavily tuned).

The latter one is really important for real life Haskell on the server, where you can sometimes can get some crash that only happens once a day under very specific conditions. Knowing where the crash happens is then *very* useful.

-- Johan