> > Even when using precompiled headers, .pch files can get pretty big, > > and they must still be loaded, > > They do? Odd, on my platform, we only mmap them. If one > doesn't touch them (and nothing else near them), they aren't > loaded for me. > > > which takes time. > > mmap is fairly quick (as compared to compilation speed).
I didn't know that. Thanks for the explanation. Otherwise I am deliberately using cygwin for testing, so that any speed-up or slowdown is more easily observed. Obviously cygwin doesn't implement mmap very efficiently since big pchs actually slow things down. > > The main question I guess is: How difficult is to implement this - > > frepo2 functionality? > > Trivial enough, if you want to try it, assuming you want to > put the #ifndef NO_TEMPLATE_INSTANTIATION into your code manually. This was the assumption from the start. Basically I want the .h file to tell the compiler: "This is my template and here (within #ifdef NO_TEMPLATE_INSTANTIATION) you can find the definitions required to instantiate it." The -frepo2 switch would then translate to: "Please ignore all template definitions as long as you can." (i.e. until the linking stage). > > If it is relatively simple and a patch is made, we can test all we > > want and then decide whether it is worth having it in the > > compiler or not. > > Feel free to do this if you want. I think we should be able > to provide enough hints and pointers to allow you to complete > the code. I'll start poking around the code and see what I come up with. Is there a tutorial (or HOWTO) for new gcc compiler writer wannabes?
