<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/67138>67138</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Linker Difference before and after opt
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          LRY89757
      </td>
    </tr>
</table>

<pre>
    code as below:
```cpp
#include <vector>

static int varargs_func2(int X,...) {
    int result = 0;
    int arr[] = {4, 5, 6};
    result += arr[0] - arr[X];
 return result;
}

int main() {
    int result = varargs_func2(1);
    return result;
}
```

our command is:
```
    commands = {
        "clang++": ["clang++", "-O0", "-mllvm", "--debug", "a.cpp", "-S", "-emit-llvm", "-o", file]
 "opt":[ "opt", file, "-O3", "--debug", "-mtriple=x86_64-unknown-linux-gnu", "-o", file_after_opt],
 "llc_before":[ "llc", file, "-O3","-filetype=obj", "--debug", "-mtriple=x86_64-unknown-linux-gnu", "-o", exe_before_opt + ".o"],
 "llc_after":[ "llc", file_after_opt, "-O3","-filetype=obj", "--debug", "-mtriple=x86_64-unknown-linux-gnu", "-o", exe_after_opt + ".o"],
        "linker_before":["clang", exe_before_opt + ".o", "-o", exe_before_opt],
        "linker_after":["clang", exe_after_opt + ".o", "-o", exe_after_opt],
    }
```

the linker before output is 0, but the linker after output is 1.


</pre>
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