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Denis Dupeyron wrote: |
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> In bug #139412, I ask Paul de Vriese why he thinks python should die |
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> on --fast-math instead of just filtering it. Here's his answer : |
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> |
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> "Denis, quite simple. -ffast-math is broken and short-sighted for a |
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> global flag. |
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> Filtering gives the shortsighted message that it works globally, while |
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> it is |
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> not suited for any package not specifically tested for it. As it breaks |
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> python, |
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> dieing makes people understand that it does not work on python. It is |
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> better |
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> than the alternative of not looking for it at all." |
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Ebuilds shouldn't die on anything according to the non-interactive portage |
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philosophy. I don't know how official that philosophy is though. |
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> This, for me, triggers 3 questions that are gentoo-dev@ material : |
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> |
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> 1) Should all ebuilds that currently filter --fast-math die on its |
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> presence instead of filtering it ? |
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No, that would be a major pain in the ass for anyone wanting to use -fast-math, |
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which does have legitimate uses. |
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> 2) If yes, are there any other flags that ebuilds should die on ? |
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There's a million, and they're constantly changing. For example, |
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-frename-registers is generally safe on GCC 3.4, broken in 4.0, and enabled by |
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default on 4.1. |
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> 3) Suppose that -ftracer, for example, is one of those, and knowing |
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> that enabling -fprofile-use enables -ftracer, shouldn't ebuilds also |
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> die on use of -fprofile-use ? It's only an example, this situation |
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> will exist for other pairs of flags. |
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> |
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> The hidden question behind these three is : shouldn't we have a |
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> "something" that enables us to safely handle this kind of situations ? |
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> Like some kind of system- and/or architecture-wide flag mask that |
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> could be overriden by the ebuild and/or the user (at his own risk) ? |
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> This could potentialy reduce the number of bugs that poor old bugzie |
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> has to cope with, and simplify ebuild writing and maintenance. |
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Users playing with CFLAGS get to keep the pieces. Trying to dummy-proof the |
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system doesn't help anyone but the dummies. ;) |
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--de. |
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