Fix issue 21737: shared opApply does not compile

[thewilsonator]

cc @TurkeyMan

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21737	enhancement	shared opApply does not compile

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#12290"

[BorisCarvajal]

This seems to work:

diff --git a/src/dmd/statementsem.d b/src/dmd/statementsem.d
index c2e83c58c..dc4b788be 100644
--- a/src/dmd/statementsem.d
+++ b/src/dmd/statementsem.d
@@ -2036,6 +2036,8 @@ else
         fs.cases = new Statements();
         fs.gotos = new ScopeStatements();
         auto fld = new FuncLiteralDeclaration(fs.loc, fs.endloc, tf, TOK.delegate_, fs);
+        if (tfld && tfld.isShared())
+             fld.storage_class |= STC.shared_;
         fld.fbody = fs._body;
         Expression flde = new FuncExp(fs.loc, fld);
         flde = flde.expressionSemantic(sc);

[thewilsonator]

Indeed it does. Thanks. FYI when pasting diffs after the three ` put diff to get the syntax highlights (i've done that for you here).

[thewilsonator]

Lightbulb: function (as opposed to function pointers) are immutable.

[WalterBright]

I'm not so sure making this compile is a good idea. Many very reasonable shared access ideas turned out to be fundamentally broken years later.

[RazvanN7]

Honestly, I'd wish we could deprecate the entire opApply thing.

[WalterBright]

The error is:

Test 'compilable/issue21737.d' failed. The logged output:
dmd -conf= -m64 -Icompilable -preview=nosharedaccess  -fPIC  -odgenerated/compilable -ofgenerated/compilable/issue21737_0.o  -c compilable/issue21737.d 
druntime/import/core/atomic.d(582): Error: direct access to shared `val` is not allowed, see `core.atomic`
compilable/issue21737.d(9): Error: template instance `core.atomic.atomicOp!("+=", int, int)` error instantiating
compilable/issue21737.d(47): Error: direct access to shared `s` is not allowed, see `core.atomic`
compilable/issue21737.d(50): Error: direct access to shared `s` is not allowed, see `core.atomic`
compilable/issue21737.d(53): Error: direct access to shared `s` is not allowed, see `core.atomic`
compilable/issue21737.d(62): Error: direct access to shared `s.result` is not allowed, see `core.atomic`