On Mon, 14 Mar 2022 08:19:41 GMT, Florian Weimer <[email protected]> wrote:
> > Thanks a lot, Florian! I got it to work under Linux x64.
>
> Great!
>
> > My error was that I had declared the label in C++ as `extern void*
> > SafeFetch_continuation`. Declaring it as `extern char
> > _SafeFetch32_continuation[] __attribute__ ((visibility ("hidden")));` as
> > you suggested does the trick. I'm not sure I understand the difference.
>
> Your approach might have worked as well, but you would have to use
> `&SafeFetch_continuation` on the C++ side. Arrays work directly because of
> pointer decay.
Ah, that makes sense. I wondered why the address did not look like a code
pointer in C++.
Anyway, got Linux x86_32 working too. Now I am working on aarch64.
>
> Anyway, from what I've seen, the array is more idiomatic.
>
> > > It doesn't hurt, but the Itanium ABI does not mangle such global data
> > > symbols, so it's not strictly needed.
> >
> >
> > I don't understand this remark, what does Itanium have to do with this?
>
> The [C++ ABI definition](https://github.com/itanium-cxx-abi/cxx-abi) is
> probably Itanium's most lasting contribution to computing. I think it's used
> on most non-Windows systems these days, not just on Linux, and of course on
> all kinds of CPUs.
Interesting to know. Thanks!
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PR: https://git.openjdk.java.net/jdk/pull/7727