Hello,
During compilation on linking stage I get strange errors (LDC):
lld-link: error: undefined symbol: _D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh4typeMxFNbNdNeZC8TypeInfo
>>> referenced by E:\Programs\LDC2\import\std\variant.d:753
>>>               .dub\obj\builder.obj:(_D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh__T4peekTQDhZQkMNgFNdZPNgAyu)                       referenced by E:\Programs\LDC2\import\std\variant.d:753
>>>               .dub\obj\builder.obj:(_D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh__T4peekTQBwZQkMNgFNdZPNgAAyu)                      referenced by E:\Programs\LDC2\import\std\variant.d:820
>>>               .dub\obj\builder.obj:(_D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh__T3getTQEdZQjMNgFNdZNgSQFxQEs__TQEmTQEjTQEjZQEy)

How to solve?
This is the first time when linking fails on Phobos library.

On Tue, Oct 22, 2019 at 2:20 PM Andrey via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:
>
> Hello,
> During compilation on linking stage I get strange errors (LDC):
> lld-link: error: undefined symbol:
> _D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh4typeMxFNbNdNeZC8TypeInfo
> >>> referenced by E:\Programs\LDC2\import\std\variant.d:753
> >>>
> >>> .dub\obj\builder.obj:(_D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh__T4peekTQDhZQkMNgFNdZPNgAyu)                       referenced by E:\Programs\LDC2\import\std\variant.d:753
> >>>
> >>> .dub\obj\builder.obj:(_D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh__T4peekTQBwZQkMNgFNdZPNgAAyu)                      referenced by E:\Programs\LDC2\import\std\variant.d:820
> >>>
> >>> .dub\obj\builder.obj:(_D3std7variant__T8VariantNVmi56TSQBf8typecons__T5TupleTAyuTSQCgQCf__TQCaVmi32TSQCzQBu__TQBoTAQBmTQBqZQCbTQnTQCbZQDrZQCqTQBcTQCrZQEh__T3getTQEdZQjMNgFNdZNgSQFxQEs__TQEmTQEjTQEjZQEy)
>
> How to solve?
> This is the first time when linking fails on Phobos library.

Have you try to clean all caches? Try to remove .dub folder

On Tuesday, 22 October 2019 at 12:57:45 UTC, Daniel Kozak wrote:
> Have you try to clean all caches? Try to remove .dub folder

I removed .dub folder but this error appears again.

On Tuesday, 22 October 2019 at 13:07:54 UTC, Andrey wrote:
> On Tuesday, 22 October 2019 at 12:57:45 UTC, Daniel Kozak wrote:
>> Have you try to clean all caches? Try to remove .dub folder
>
> I removed .dub folder but this error appears again.

Try the "-allinst" option. It's possibly a bug with speculative template instantiation.
"-allinst" deactivates speculation and everything is always instantiated and therefore present in the object files.

On Wednesday, 23 October 2019 at 20:45:55 UTC, baz wrote:
> On Tuesday, 22 October 2019 at 13:07:54 UTC, Andrey wrote:
>> On Tuesday, 22 October 2019 at 12:57:45 UTC, Daniel Kozak wrote:
>>> Have you try to clean all caches? Try to remove .dub folder
>>
>> I removed .dub folder but this error appears again.
>
> Try the "-allinst" option. It's possibly a bug with speculative template instantiation.
> "-allinst" deactivates speculation and everything is always instantiated and therefore present in the object files.

If `-allinst` works, then please minimize the testcase and put it in our bugtracker. We know there are template culling problems but it only appears in very complex code. I have not been able to reduce it to less than a < 20k line problem across a ton of files...

-Johan