fish complains about startup script

[matthuszagh]

The exact error is

~/.config/fish/config.fish (line 1): Unsupported use of '='. In fish, please use 'set GPG_AGENT_INFO /home/matt/.gnupg/S.gpg-agent:2993:1'.
from sourcing file ~/.config/fish/config.fish
        called during startup

The config.fish file does not contain an = sign in the first line so I'm not exactly sure what this is about. Maybe its loading a general initialization script (possibly as part of the bash configuration), which is causing the error?