EnvironmentFile parsing: line continuation characters at the end of comments are not ignored

[rocketraman]

systemd version the issue has been seen with

253

Used distribution

Fedora CoreOS 38

Linux kernel version used

6.2.15-300.fc38.x86_64

CPU architectures issue was seen on

x86_64

Component

systemd

Expected behaviour you didn't see

I have a unit that references an EnvironmentFile. My environment file looks like this:

# This is a comment \
FOO=bar

My expectation is that FOO will be set to bar, as the line-continuation character should be ignored since it is part of a comment.

For reference: POSIX shells (tried with sh and bash) ignore the line-continuation character at the end of a comment. For example:

#!/bin/sh
# This is a comment \
FOO=bar
echo $FOO

will print bar.

Unexpected behaviour you saw

systemd is parsing the line continuation character at the end of the comment line, and thus including the next FOO=bar line as part of the comment.

Steps to reproduce the problem

No response

Additional program output to the terminal or log subsystem illustrating the issue

No response