Underscore in codeblock caption breaks output with listings

[sys9kdr]

I've got problem with codeblock captions and listings.
Underscores in codeblock caption cause PDF generation error with --listings option.

pandoc version

2.10.1

> pandoc --version
pandoc 2.10.1
Compiled with pandoc-types 1.21, texmath 0.12.0.2, skylighting 0.8.5
Default user data directory: /Users/ghnoda/.local/share/pandoc or /Users/ghnoda/.pandoc
Copyright (C) 2006-2020 John MacFarlane
Web:  https://pandoc.org
This is free software; see the source for copying conditions.
There is no warranty, not even for merchantability or fitness
for a particular purpose.

Steps to reproduce

1. Create this markdown file, sample.md.

```{caption='some_code.c'}
code here
```

2. Error caused when building pdf with listings options and lualatex.

> pandoc -o output.pdf --pdf-engine=lualatex --listings sample.md
Error producing PDF.
! Missing $ inserted.
<inserted text> 
$
l.59 \begin{lstlisting}[caption={some_code.c}]

• latex output with same file and options

> pandoc -t latex --listings sample.md
\begin{lstlisting}[caption={some_code.c}]
code here
\end{lstlisting}

[jgm]

What is required here? A backslash-escape \_?

[sys9kdr]

Yes. I think the latex output should include \_.

\begin{lstlisting}[caption={some\_code.c}]
code here
\end{lstlisting}