r213657 - Provide extra information in the "integer constant is too large" diagnostic. This will be used to improve other diagnostics.

[Aaron Ballman]

On Tue, Jul 22, 2014 at 8:45 PM, Richard Smith <richard at metafoo.co.uk> wrote:
> On Tue, Jul 22, 2014 at 5:38 PM, Aaron Ballman <aaron at aaronballman.com>
> wrote:
>>
>> How do these sound to you?
>>
>> On Tue, Jul 22, 2014 at 8:13 PM, Richard Smith <richard at metafoo.co.uk>
>> wrote:
>> > +def err_integer_literal_too_large : Error<
>> > +  "integer literal is a value that cannot be represented as
>> > %select{a|an}0
>> > "
>> > +  "%select{signed|unsigned}0 integer">;
>> >
>> > I don't think the "is a value that" adds anything here. Also, I'd like
>> > to
>> > see something that more directly says we don't have a signed/unsigned
>> > integer type large enough.
>>
>> "integer literal is too large to be represented in %select{a|an}0
>> %select{signed|unsigned}0 integer type"
>
>
> Perhaps "... to be represented in any %select{signed |}0integer type"?

Works for me.

>
>>
>> >  def err_integer_too_large : Error<
>> > -  "integer constant is larger than the largest %0-bit unsigned integer
>> > type">;
>> > -def ext_integer_too_large_for_signed : ExtWarn<
>> > -  "integer constant is larger than the largest %0-bit signed integer
>> > type">,
>> > +  "integer constant evaluates to value %0 that cannot be represented as
>> > a "
>> > +  "%1-bit %select{signed|unsigned}2 integer">;
>> >
>> > Please rename this to something about ICEs, and move it to
>> > DiagnosticSemaKinds next to the existing err_ice_ diagnostics. (This is
>> > pretty similar to ext_cce_narrowing...)
>> >
>> >
>> > +def ext_integer_literal_too_large_for_signed : ExtWarn<
>> > +  "integer literal is a value that cannot be represented as a signed
>> > integer, "
>> > +  "and will instead be interpreted as unsigned">,
>> >
>> > Again, mentioning integer types and not just integers would make this
>> > clearer.
>>
>> "integer literal is too large to be represented in a signed integer
>> type, and will instead be interpreted as unsigned integer type"
>
>
> Can we specify the type here? I think it's always 'unsigned long long' when
> we reach this diagnostic.

It's not always unsigned long long -- this gets used in EvaluateValue
in PPExpressions.cpp, and we only set the resulting value to unsigned,
but not change its type.

~Aaron