GCC Bootstraps

As anyone working on GCC would know, GCC bootstrap times are getting worse. It is so excruciating on some platforms that it is nearly impossible to keep those platforms up-to-date even if people want to. Of course, many more optimisations, new languages and their ever-bloating runtimes, more comprehensive support for language standards, etc. make it inevitable that bootstrap times increase, but does it really have to increase so much?

On my home PC, a "c,c++,java" bootstrap takes more than three hours and a complete testsuite run takes a lot of time as well. Considering that any change to the main compiler needs a complete bootstrap and testsuite run twice over (once without and once with your patch), that too in the best case of no regressions, is it small wonder that many people who might want to otherwise volunteer to help with GCC development just cannot afford to? I have only so much free time left after my job and my family and many a time I feel I am much better off reading a good book or watching a good movie, for example, than literally losing sleep over GCC. Small wonder then that almost all of the prolific contributors to GCC either work on it as a part of their job or on really fast machines with loads of memory (or both).


Perhaps it is not a good idea after all to have a single compiler codebase support so many languages and runtimes at the same time. Perhaps it would be better to start over by creating a well-defined (in terms of the structure and contract) set of language and platform-independent intermediate languages (different avatars of GENERIC and RTL) and have the front-ends and the back-ends as separate projects from the core framework. Of course, if things were this simple people would have done it already, but a man can dream, can't he?

(Originally posted on Advogato.)

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