gcc: Update coroutine header from master

[bustercopley]

Third patch prevents multiple definition errors when including header "coroutine" in more than one translation unit. Applying the other two intermediate commits to simplify patch management.

[Biswa96]

What is build.cmd?

[bustercopley]

What is build.cmd?

Oops, that was careless. It's just something I keep around locally for invoking bash commands from a cmd.exe environment. I'll replace the commit.

[lazka]

will this be in 10.3 (next week)?

[bustercopley]

No, not as far as I can see. As of the advertised commit the first of the three commits in my PR had been cherry-picked to the 10.3 release candidate, and the other two commits had not.

[bustercopley]

Ah, releases/gcc-10 is the rc branch. Same deal there: just the first patch has been cherry-picked.

[bustercopley]

I've mentioned it on the gcc mailing list.

[lazka]

Given the upstream feedback do you still think we should backport this?

[bustercopley]

Yes, I think so, after we land 10.3. Users will be better served by having something that works, even if it means they need to recompile when the 'final' ABI is settled, potentially in version 10.4. (Just my opinion.)

[lazka]

ok, sounds good

[lazka]

gcc update in #8320

[bustercopley]

Updated and rebased onto Astrum-polaris:updates.

[bustercopley]

Fixed, I think.
This PR consists of one commit (8206161).
It doesn't apply cleanly to current master so I rebased onto f34c221 (PR #8320, gcc update to 10.3).
So this PR branch is 4 commits ahead of master (3 for #8320, 1 for #8263).
But you will probably want to merge #8320 first, then take just the final commit from here.

Hope this helps.

Here are some notes on what's in my commit.

Commits to libstdc++-v3/include/std/coroutine (in reverse chronological order) from git://gcc.gnu.org/git/gcc.git:

• In branch master as of now (2a26351b598):

[F] 26a3f288f18 * libstdc++: Make coroutine_handle<_Promise>::from_address() noexcept [PR 99021]
[E] 99dee82307f * Update copyright years.
[D] 94fd05f1f76 * libstdc++: Define noop coroutine details private and inline [PR 95917]
[C] 2c2278f300c * libstdc++: Remove inheritance from std::coroutine_handle<> [LWG 3460]
[B] f1b6e46c417 * libstdc++, coroutine: Add missing constexpr markers.
[A] b9c91b7f327 * coroutines: Fix handling of non-class coroutine returns [PR94759]
    dcf69ac5448 * coroutines, libstdc++-v3: Update to n4861 C++20 DIS.
    ee26baf4a81 * coroutines: Rename the coroutines cpp builtin.
    49789fd0837 * [C++ coroutines] Initial implementation.

• In tag releases/gcc-10.3.0:

[F] fa183497cf2 * libstdc++: Make coroutine_handle<_Promise>::from_address() noexcept [PR 99021]
[B] 517fb88b8a9 * libstdc++, coroutine: Add missing constexpr markers.
[A] b9c91b7f327 * coroutines: Fix handling of non-class coroutine returns [PR94759]
    dcf69ac5448 * coroutines, libstdc++-v3: Update to n4861 C++20 DIS.
    ee26baf4a81 * coroutines: Rename the coroutines cpp builtin.
    49789fd0837 * [C++ coroutines] Initial implementation.

The merge base is [A]. The fix is [D]. It's easiest to include [C] as well. Here's what I've done:

In gcc repo

• reset to gcc-10.3.0
• revert [F] fa183497cf2 (cherry pick of 26a3f288f18)
• cherry pick [C] 2c2278f300c, [D] 94fd05f1f76, [F] 26a3f288f18 from master
• create patches from those 4 commits (1 revert, 3 cherry picks)

There are now 4 patches for #8263 but in effect they just cherry pick two commits ([C] and [D]).

In MINGW-packages repo

• reset to Astrum-polaris:updates (f34c221) (gcc update in gcc: Update to 11.1.0 #8320)
• add a single commit (8206161) in MINGW-packages (apply the 4 patches for gcc: Update coroutine header from master #8263)
• force-push 8206161 to this PR (gcc: Update coroutine header from master #8263)

[lazka]

Thanks. We will likely wait a bit after 10.3 to rule out any regressions before patching more. Please be patient :)

[bustercopley]

This is in 11.1 (next week, maybe). I think it can wait until then.