RFR: 8343984: Fix Unsafe address overflow [v5]

[Per Minborg]

On Tue, 12 Nov 2024 11:24:24 GMT, Shaojin Wen <swen at openjdk.org> wrote:

>> In the JDK code, there are some places that may cause Unsafe offset overflow. The probability of occurrence is low, but if it occurs, it will cause JVM crash.
>
> Shaojin Wen has updated the pull request incrementally with one additional commit since the last revision:
> 
>   rename address to offset, from @AlanBateman

> I want to add such a test case, but I am worried that it will consume too many resources during the build process.
> 
> ```java
> /**
>  * @test
>  * @bug 8343984
>  * @summary Test that the append capacity is close to Integer.MaxValue
>  * @run main/othervm -Xms6g -Xmx6g HugeAppend
>  */
> 
> public final class HugeAppend {
>     public static void main(String[] args) {
>         StringBuilder buf = new StringBuilder();
>         int loop4 = Integer.MAX_VALUE / 4;
>         for (int i = 0; i < loop4; i++) {
>             buf.append(true);
>         }
> 
>         buf.setLength(0);
>         int loop5 = Integer.MAX_VALUE / 5;
>         for (int i = 0; i < loop5; i++) {
>             buf.append(false);
>         }
>     }
> }
> ```

Yeah. I think it is reasonable to leave out such tests.

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PR Comment: https://git.openjdk.org/jdk/pull/22027#issuecomment-2470383131