Fix Issue 21701 - casWeak is not implemented

[rymrg]

dmd aliases casWeak to casStrong.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21701	normal	casWeak is not implemented

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 "stable + druntime#3392"

[RazvanN7]

@rymrg please rebase this to get rid of the spurious failures.

[rymrg]

@rymrg please rebase this to get rid of the spurious failures.

@RazvanN7 Last commit to stable is 4 days ago. #3396 hasn't been merged yet.

[ibuclaw]

What about GDC and LDC?

[rymrg]

What about GDC and LDC?

ldc has its own fork of druntime. So I planned to cherry pick and add the related code after this is merged. Where is druntime located for gdc?

[ibuclaw]

What about GDC and LDC?

ldc has its own fork of druntime. So I planned to cherry pick and add the related code after this is merged. Where is druntime located for gdc?

Same file as where you're editing here.

druntime/src/core/internal/atomic.d

Lines 856 to 872 in bcf3ecc

	bool atomicCompareExchangeWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T)(T* dest, T* compare, T value) pure nothrow @nogc @trusted
	if (CanCAS!T)
	{
	return atomicCompareExchangeImpl!(succ, fail, true)(dest, compare, value);
	}
	bool atomicCompareExchangeStrong(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T)(T* dest, T* compare, T value) pure nothrow @nogc @trusted
	if (CanCAS!T)
	{
	return atomicCompareExchangeImpl!(succ, fail, false)(dest, compare, value);
	}
	bool atomicCompareExchangeStrongNoResult(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T)(T* dest, const T compare, T value) pure nothrow @nogc @trusted
	if (CanCAS!T)
	{
	return atomicCompareExchangeImpl!(succ, fail, false)(dest, cast(T*)&compare, value);
	}

[ibuclaw]

OK

[rymrg]

@RazvanN7 I'm having hard time getting the rebase to work correctly.

[RazvanN7]

I normally do:

git checkout master
git pull
git checkout $branch
git rebase master
git push ...