On Fri, Sep 6, 2013 at 10:14 AM, Mike Stump <mikest...@comcast.net> wrote: > On Sep 5, 2013, at 11:54 PM, Richard Biener <richard.guent...@gmail.com> > wrote: >> Most of the GCC headerfiles do not include all their required headers but >> rely on .c files doing that (in the appropriate order). I somehow like >> that though I cannot explain why ;) > > Very old school. I can explain why I don't like it, but I'll resist. The > universal standard is for each header to include all it needs and for the > ordering of includes not to matter any. Deviations from this are the > exception and should virtually never should be the case. > >> Also grepping for #includes I see that this doesn't seem to be true anymore. > > Yeah, everyone else hates the old school style with a passion, it was never a > good idea. :-) When they come across it, people have a tendency to fix the > headers as broken and over time, all the dependencies eventually get added.
Well, I still think you cannot randomly change include file order in GCC. At least some #ifdef ... hackery in some headers will suddenly break (that is, change outcome) if you include for example tm.h before or after it. But yes, making all dependencies explicit puts #includes where they belong and shows where header refactoring would make sense. It also removes weird includes from .c files that are only necessary to make included required headers not break. Richard.
