How to escape a pipe char in a code statement in a markdown table?

As of March 2017 using escaped pipes is much easier: \| See other answers.

If you remove the backticks (`), using the | hack works

      a     |  r  
------------|-----
 `a += x;`  |  r1
 a |= y;  |  r2

and produces the following output

Alternatively, you can replace the backticks (`) with a <code></code> markup which fixes the issues more nicely by preserving the rendering

      a     |  r  
------------|-----
 `a += x;`  |  r1
<code>a &#124;= y;</code>  |  r2

generating the following output

this works fine in github markdown:

|       a     |  r  
| ------------|-----
|  `a += x;`  |  r1
|  `a \|= y;` |  r2

very similar to https://stackoverflow.com/a/45122039/1426932 but with added | in first column (it didn't render well in comments so I'm adding an answer here).

note that outside a table cell, a \|= y; will render the backslash, but inside a table cell, it won't.

As of mid-2017, the pipe may simply be escaped with a backslash, like so: \|

This works both inside and outside of backticks.

The HTML code may now be used again, too, but only outside of backticks.

Previous answer:

As of March 2017, the accepted answer stopped working because GitHub changed their markdown parser. Using another unicode symbol that resembles a pipe seems to be the only option right now, e.g.:

ǀ (U+01C0, Latin letter dental click)

∣ (U+2223, Symbol divides)

⎮ (U+23AE, Integral Extension)

You can escape the | in a table in GFM with a \ like so:

|      a     |  r  
|------------|-----
| `a += x;`  |  r1
| `a \|= y;` |  r2

See https://github.github.com/gfm/#example-191 or https://github.com/dotnet/csharplang/pull/743 for an example.