[lld] [lld][WebAssembly] Return 0 for synthetic function offsets (PR #96134)

[Heejin Ahn via llvm-commits]

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@@ -0,0 +1,31 @@
+target triple = "wasm32-unknown-emscripten"
+
+define void @foo(i32 %a, i32 %b) !dbg !6 {
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aheejin wrote:

I don't know. They are not marked as `weak`, so it's weird... I tested with system (x86) clang and gcc and they all seem to error out.

When we do this by LTO, meaning running `wasm-ld` directly on bitcode, they error out saying duplicate definition. When does this "signature mismatch" occur usually? When a definition and a callsite do not match in the signature?

https://github.com/llvm/llvm-project/pull/96134