RFR: 8290059: Do not use std::thread in panama tests [v2]

[Thomas Stuefe]

On Fri, 22 Jul 2022 16:45:55 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

>> This patch removes the use of std::thread from the `java.lang.foreign` tests, and switches to the OS specific thread APIs, in order to change things such as the stack size on some platforms where this is required in the future (see the JBS issue).
>> 
>> This is done by adding a small header-only library that exposes a function to run code in freshly spawned threads (`run_async`).
>> 
>> Testing: Running the affected tests on platforms that implement the linker.
>
> Jorn Vernee has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fixes

Hi @JornVernee,

good job and thanks for doing it so quickly. Looks good, module the GetLastError comment.

About the stack size and Alpine, I am fine with doing the Aĺpine-specific fix in a follow-up, or you can do it as part of this change. Strictly speaking its not part of this bug report to adjust the stack size.

If you fix the GetLastError issue, I don't need another look.
Thanks, Thomas

test/lib/native/testlib_threads.h line 50:

> 48: static void fatal(const char* message) {
> 49:     perror(message);
> 50:     exit(-1);

Won't work as intended for Windows APIs. I would print the result of `GetLastError()` instead.

Alternatively I am fine fine with just omitting the error code, because I think the old tests did not handle errors either. Or did we catch std::thread exceptions somewhere?

test/lib/native/testlib_threads.h line 61:

> 59:     helper->proc(helper->context);
> 60:     return 0;
> 61: }

I'm curious, does this only exist because of the DWORD vs void* return value size of the native thread functions? I wondered why you don't just pass the test procedure to the thread start API directly.

About stdcall, does Oracle still build Windows 32bit?

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Marked as reviewed by stuefe (Reviewer).

PR: https://git.openjdk.org/jdk/pull/9599