[wasm-ld] allow-multiple-definition flag unsupported

[mzukovec]

It seems to me that the allow-multiple-definition is not supported in wasm-ld. Is there any specific reason why this is not currently supported? Due the the missing flag, some of the codebases are not easily ported to WASM due to the legacy.

I realize that the duplicate symbol should be resolved on another level, but it is still very annoying that the whole dependency chain for some project must be revisited and fixed.

[llvmbot]

@llvm/issue-subscribers-lld-wasm

Author: None (mzukovec)

It seems to me that the `allow-multiple-definition ` is not supported in `wasm-ld`. Is there any specific reason why this is not currently supported? Due the the missing flag, some of the codebases are not easily ported to WASM due to the legacy.

I realize that the duplicate symbol should be resolved on another level, but it is still very annoying that the whole dependency chain for some project must be revisited and fixed.

[sbc100]

I don't think there is a particular reason this flag is missing. We tended to add just the flags that folks needed, and this some seams fairly reasonable.

Would you like to send a PR, or wait for myself or someone else to do it?

[mzukovec]

Let me give it a shot. I’ll ping if it doesn’t go as planned.

[mzukovec]

@sbc100
This should do it: #97699

[andrewmd5]

Has this landed in a release yet?

[sbc100]

The change landed in llvm after the branch point so its not in the v19 branch. If you use emscripten we use tip-of-free llvm so its already available there. If you want to see it in the next v19 point release you could request that it gets backported, but since its a new feature and not a bugfix I'm not sure it makes sense to backport.