5.7. Rescuing cached components

5.7. Rescuing cached components

By default, Eeschema loads component symbols out of the libraries according to the set paths. This can cause a problem when loading a very old project: if the symbols in the library have changed since they were used in the project, the ones in the project would be automatically replaced with the new versions. The new versions might not line up correctly or might be oriented differently, leading to a broken schematic.

However, when a project is saved, a cache library is saved along with it. This allows the project to be distributed without the full libraries. If you load a project where symbols are present both in its cache and in the system libraries, Eeschema will scan the libraries for conflicts. Any conflicts found will be listed in the following dialog:

You can see in this example that the project originally used a diode with the cathode facing up, but the library now contains one with the cathode facing down. This change could ruin the project! Pressing OK here will cause the old symbol to be saved into a special “rescue” library, and all the components using that symbol will be renamed to avoid naming conflicts.

If you press Cancel, no rescues will be made, so Eeschema will load all the new components by default. Because no changes were made, you can still go back and run the rescue function again: choose “Rescue Cached Components” in the Tools menu to call up the dialog again.

If you would prefer not to see this dialog, you can press “Never Show Again”. The default will be to do nothing and allow the new components to be loaded. This option can be changed back in the Component Libraries preferences.