How to revert to an older version of flycast on rpi4

[rejesterd]

Sometimes when you upgrade flycast, you might find that a new defect has been introduced since you last updated or installed. In that case, you may want to revert to using your previous version of flycast. Here's how:

1.) Determine your previous version's commit id. It's possible that the retropie setup directory contains the log from when you last installed/updated flycast. To find out, run..

pi@raspberrypi:~ $ cd ~/RetroPie-Setup/logs
pi@raspberrypi:~/RetroPie-Setup/logs $ flycastver () { for fname in *.log.gz; do    zcat "$fname" | grep -A 1 "Cloning into '/home/pi/RetroPie-Setup/tmp/build/lr-flycast'"; done; }
pi@raspberrypi:~/RetroPie-Setup/logs $ flycastver

So here, we've just created a function called 'flycastver' and then ran it. On my system, this outputs the following:

Cloning into '/home/pi/RetroPie-Setup/tmp/build/lr-flycast'...
HEAD is now in branch 'master' at commit 'c59eac05f008ae58e13f88091be8fa2188eb195c'

So my flycast commit number is c59eac05f008ae58e13f88091be8fa2188eb195c. I can look this up on https://github.com/libretro/flycast/commits/master. For example, mine is here:

https://github.com/libretro/flycast/commit/c59eac05f008ae58e13f88091be8fa2188eb195c

If the 'flycastver' function doesn't return anything, then you'll have to go to https://github.com/libretro/flycast/commits/master and take a guess as to which commit you installed (based on the date of each commit).

2.) Checkout that commit id after changing back to your home directory (by running "cd ~/"):

pi@raspberrypi:~ $ git clone -n https://github.com/libretro/flycast
pi@raspberrypi:~ $ cd flycast
pi@raspberrypi:~/flycast $ git checkout c59eac05f008ae58e13f88091be8fa2188eb195c

3.) Patch the Makefile:

pi@raspberrypi:~/flycast $ patch Makefile /home/pi/RetroPie-Setup/scriptmodules/libretrocores/lr-flycast/01_flags_fix.diff

4.) Build the flycast library:

pi@raspberrypi:~/flycast $ make platform=rpi4

That will take a few minutes to build. When it's done, you should now have a copy of 'flycast_libretro.so' in your ~/flycast/ directory.

5.) Rename your current copy of the flycast library:

pi@raspberrypi:~/flycast $ cd /opt/retropie/libretrocores/lr-flycast/
pi@raspberrypi:/opt/retropie/libretrocores/lr-flycast $ mv flycast_libretro.so flycast_libretro.so.bak

6.) Copy your newly-rebuilt flycast library to replace the old one you just renamed:

pi@raspberrypi:/opt/retropie/libretrocores/lr-flycast $ sudo cp ~/flycast/flycast_libretro.so .

Cheers.

[barbudreadmon]

@rejesterd said in How to revert to an older version of flycast on rpi4:

Sometimes when you upgrade flycast, you might find that a new defect has been introduced since you last updated or installed. In that case, you may want to revert to using your previous version of flycast

How about writing a report instead ? Your issue won't be fixed if we are unaware of it.

[rejesterd]

@barbudreadmon I don't have an issue with flycast. I was testing an issue for another forum member, so I wanted to downgrade to their version. But yes, I will certainly report any defects I come across.