RFR: 8312190: Fix c++11-narrowing warnings in hotspot code

[David Holmes]

On Mon, 17 Jul 2023 18:31:41 GMT, Daniel Jeliński <djelinski at openjdk.org> wrote:

> This patch fixes compilation warnings produced by Clang when compiling on Windows.
> 
> Clang emulates MSVC behavior and uses `int` for enumeration types that do not explicitly specify the underlying type. This patch sets an explicit underlying type for 3 enumerations to fix the warnings.
> 
> See Microsoft's documentation of [Zc:enumTypes](https://learn.microsoft.com/en-us/cpp/build/reference/zc-enumtypes?view=msvc-170) for more information.

Seems reasonable.

Thanks.

src/hotspot/share/utilities/debug.hpp line 248:

> 246: 
> 247: // types of VM error - originally in vmError.hpp
> 248: enum VMErrorType : unsigned int {

Why 'unsigned int' when the other changes are `uint`?

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Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/14907#pullrequestreview-1534191903
PR Review Comment: https://git.openjdk.org/jdk/pull/14907#discussion_r1266231566