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

[Heejin Ahn via llvm-commits]

================
@@ -0,0 +1,31 @@
+target triple = "wasm32-unknown-emscripten"
+
+define void @foo(i32 %a) !dbg !6 {
+  ret void
+}
+
+define void @test0() !dbg !10 {
+entry:
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aheejin wrote:

I generated these tests from `.c` file and manually removed some unnecessary parts, and I think I left some `entry`s. Removed them for consistency.

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