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Re: [PATCH] Improve PR30911 and PR31023, Ada and VRP


Hi,

> So I see only harm in the current non-existing middle-end semantics
> of integral sub-types.  Thus I recommend to disallow using them
> for variables exposed to the middle-end.

I have to agree, it is all just too error prone.  How about having
the Ada front-end add ASSERT_EXPR's (or maybe an equivalent builtin)
at points where it knows an interesting bound?  Unlike the current
situation, these should mean what they say: the value is guaranteed
to be in the range.  As such they wouldn't apply to uninitialized
variables and so forth, which would remove the need for a VRP barrier
like VIEW_CONVERT_EXPR.

Ciao,

Duncan.


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