Avoid passing null pointer to cygwin_conv_path

Author: Berrysoft

src/symbolize/gimli/libs_windows.rs

@@ -65,12 +65,11 @@ unsafe fn get_posix_path(long_path: &[u16]) -> Option<OsString> {
 
     // If `size` is 0, returns needed buffer size, including null terminator;
     // or -1 if error.
-    // Safety: **Confirmed from source:** If `size` is 0, `to` is not used.
     let name_len = unsafe {
         cygwin_conv_path(
             CCP_WIN_W_TO_POSIX,
             long_path.as_ptr().cast(),
-            core::ptr::null_mut(),
+            8 as *mut libc::c_void, // Avoid being null, and align enough
             0,
         )
     };