title: Why do I get "generic parameters may not be used in const operations" error when compiling dependencies?
body: <p>I'm trying to compile <a href="https://docs.rs/docx/latest/docx/" rel="nofollow noreferrer">the sample code</a> from the docx crate:</p>
  <pre class="lang-toml prettyprint-override"><code># Cargo.toml
  [dependencies]
  docx = &quot;1.1.2&quot;
  </code></pre>
  <pre><code>//! main.rs
  use docx::document::Paragraph;
  use docx::DocxFile;
  
  fn main() {
      let docx = DocxFile::from_file(&quot;origin.docx&quot;).unwrap();
      let mut docx = docx.parse().unwrap();
  
      let para = Paragraph::default().push_text(&quot;Lorem Ipsum&quot;);
      docx.document.push(para);
  
      docx.write_file(&quot;origin_appended.docx&quot;).unwrap();
  }
  </code></pre>
  <p>This is the full error I'm getting:</p>
  <pre class="lang-none prettyprint-override"><code>   Compiling bzip2-sys v0.1.11+1.0.8
     Compiling jetscii v0.4.4
     Compiling quote v1.0.21
     Compiling time v0.1.44
  error: generic parameters may not be used in const operations
     --&gt; /home/thwart/.cargo/registry/src/github.com-1ecc6299db9ec823/jetscii-0.4.4/src/simd.rs:109:13
      |
  109 |             T::CONTROL_BYTE,
      |             ^^^^^^^^^^^^^^^ cannot perform const operation using `T`
      |
      = note: type parameters may not be used in const expressions
  
  error: generic parameters may not be used in const operations
     --&gt; /home/thwart/.cargo/registry/src/github.com-1ecc6299db9ec823/jetscii-0.4.4/src/simd.rs:148:13
      |
  148 |             T::CONTROL_BYTE,
      |             ^^^^^^^^^^^^^^^ cannot perform const operation using `T`
      |
      = note: type parameters may not be used in const expressions
  
  error: could not compile `jetscii` due to 2 previous errors
  </code></pre>
  <p>Why is Rust compiling jetscii? How do I fix this error?</p>