<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/84364>84364</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [WebAssembly]: `__attribute__((used))` doesn't preserve symbol
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          sunfishcode
      </td>
    </tr>
</table>

<pre>
    It appears `__attribute__((used))` doesn't cause a symbol to be preserved in the final output, on Wasm. Similarly, functions with an `export_name` are not preserved, even though it also has `no_dead_strip` in the output.

Specifically, here's a C testcase where everything is prefixed with "abc" for easy grepping:
```c
__attribute__((export_name("abc-red")))
static void abc_apple(void) {}

__attribute__((used))
static void abc_pear(void) {}

void abc_banana(void) {}

__attribute__((export_name("abc-green")))
void abc_grape(void) {}
```

`abc_apple`, `abc_pear`, and `abc_grape` are all marked with `no_dead_strip`, as expected:
```
$ clang -S -o - test.c | grep no_dead_strip
        .no_dead_strip  abc_apple
        .no_dead_strip  abc_pear
        .no_dead_strip  abc_grape
        .no_dead_strip  __indirect_function_table
```

However, the only function that gets preserved is `abc_grape`:
```sh
$ clang test.c -o test.wasm
$ wasm-tools print test.wasm | grep abc
  (func $abc_grape (;6;) (type 2)
  (export "abc-green" (func $abc_grape))
```

So it appears wasm-ld is not honoring no_dead_strip.

I can reproduce with with the clang packages in [wasi-sdk](https://github.com/WebAssembly/wasi-sdk/releases/tag/wasi-sdk-21) and with a build from current wasi-sdk and llvm git sources.

</pre>
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