Working with a copy from CVS a few days ago, I rebuilt the entire binary chain (SDL pieces, libpng, pdcurses) with VisualC (2005) instead of GCC to see if there were any differences. Everything builds and runs fine, played several games, etc.

I decided to see if profile guided opt yields any results, so I did the major DLLs first, then got around to dosbox itself. I can instrument a build and run that just fine, and it gathers a .PGC meta-information file. But if I actually try to optimize that with a new link, it fails every time (I tried multiple programs under Dosbox as examples, hence multiple runs) with a fatal error C1307, "program has been edited since profile data was collected". I am 100% sure the code was not edited between runs.

I'm wondering if the self-modifying code in Dosbox can confuse VC's profiling system - it's the only thing I can think of that's unusual going on. Interestingly I can still do a Profile Guided "Update", just not a final "Optimize". Update yields an optimized link build that works well, but I think global optimizations are ignored via that path (if my murky recollection is correct).

So anybody have this work recently, does VS2008 work as I could switch to that? It's not a huge deal because either the GCC or VS builds still work for me, just seemed odd.

-Frob