RFR: 8313882: Fix -Wconversion warnings in runtime code [v2]

[Coleen Phillimore]

On Wed, 9 Aug 2023 19:51:29 GMT, Patricio Chilano Mateo <pchilanomate at openjdk.org> wrote:

>> No, it works and is a bit better, so I made this change.
>
> I see error in some builds due to the EOF comparison though now that c is a char. I think Dean was suggesting doing the cast inside the loop.

That must have been the error I was seeing but couldn't remember.  I'm putting this back to the version I tested completely.  I don't see the point of adding another local variable here and doing the checked_cast<> until we need the char to be stored.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/15177#discussion_r1289138719