Editing the emerge --resume database (with a text editor)

When you run emerge --resume, emerge looks at /var/cache/edb/mtimedb to find the most recent entry in the resume list. Don't worry about the scary name --- this is just a JSON file with the following format:

{"info": { ... },
 "ldpath": { ... },
 "resume": { ... },
 "resume_backup": { ... },
 "starttime": 0,
 "updates": { ... },
 "version": "3.0.61"}

resume and resume_backup are the keys we're interested in.

Delete the most recent entry

When emerge fails, it will save the current state of the merge in resume. If there's already an entry there, that entry will be moved to resume_backup.

But whatever is already in resume_backup is discarded.

There is a simple fix for this: If the contents of resume_backup is important, but resume isn't, move the contents of resume_backup to resume by yourself. This emulates a successful run of emerge --resume.

You'll probably want to back up /var/cache/edb/mtimedb before attempting this change for the first time.

For this example:

"resume": {
    "favorites": [
        "kde-plasma/plasma-pa"
    ],
    "mergelist": [
        [
            "ebuild",
            "/",
            "kde-plasma/plasma-pa-6.0.3",
            "merge"
        ]
    ],
    "myopts": {
        "--regex-search-auto": "y"
    }
},
"resume_backup": {
    "favorites": [
        "@world"
    ],
    "mergelist": [ ... ],
    "myopts": {
        "--emptytree": true,
        "--jobs": 12,
        "--keep-going": true,
        "--regex-search-auto": "y"
    }
},

You would delete each line from "favorites": [ to "resume_backup": {:

"resume": {
    "favorites": [
        "@world"
    ],
    "mergelist": [ ... ],
    "myopts": {
        "--emptytree": true,
        "--jobs": 12,
        "--keep-going": true,
        "--regex-search-auto": "y"
    }
},