The linker script documentation does not mention the optional comma
that may follow an output section command or an overlay command.
In some cases, where a fill expression is used, and the next
output section command begins with an operator (e.g., "/DISCARD/"),
the comma may be required to separate the two commands.
Currently, GNU ld doesn't require the comma, but gold does.
ld/
PR gold/16804
* ld.texinfo: Document optional comma following output section
command and overlay command.