Should exhaustiveness testing be on by default?

Alexander Dunlap alexander.dunlap at
Mon May 18 23:56:16 EDT 2009

On Mon, May 18, 2009 at 7:59 PM, Robert Greayer <robgreayer at> wrote:
> On Mon, May 18, 2009 at 4:00 PM, Norman Ramsey <nr at> wrote:
>> P.S. The exhaustiveness checker does need improvement...
> Is it documented somewhere what deficiencies the exhaustiveness
> checker has (where it can report problems that don't exist or fails to
> report problems that do...), and which deficiencies can't be resolved?
> Rob

One problem is that it reports erroneous errors when combined with
ViewPatterns, which certainly ought to be fixed if
-fwarn-incomplete-patterns and -fwarn-overlapping-patterns are
switched on by default. This isn't the bug others are referring to,
though; I don't know where you'd find that information.


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