RFR: 8298128: runtime/ErrorHandling/TestSigInfoInHsErrFile.java fails to find pattern with slowdebug [v2]

[David Holmes]

On Sun, 18 Dec 2022 17:58:38 GMT, Afshin Zafari <duke at openjdk.org> wrote:

>> test/hotspot/jtreg/runtime/ErrorHandling/HsErrFileUtils.java line 138:
>> 
>>> 136:                     throw new RuntimeException("hs-err file incomplete (first missing pattern: " + currentPositivePattern.pattern() + ")");
>>> 137:                 } else {
>>> 138:                     // Impossible to reach here, where stack is not empty and currentPositivePattern which was peeked from stack is null.
>> 
>> If this is impossible to reach then why put in the null check? If the impossible were to happen you would get a NPE.
>
> `currentPositivePattern` is null checked before any usage. Therefore, the other parts of the code are guarded against NPE.
> For using `currentPositivePattern`, I should also check it against `null`. Then, the `else { ...} ` part became unreachable. I just put this part for future contributors. Maybe the comments only are enough for that.
> What is better: remove else part? or improve the comments? or both?

IMO all you need here is simply:

// Found all positive pattern?
if (!positivePatternStack.isEmpty()) {
    throw new RuntimeException("hs-err file incomplete (first missing pattern: " + currentPositivePattern.pattern() + ")");
}

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PR: https://git.openjdk.org/jdk/pull/11704