Investigate and fix issues reported by Coverity Scan

[stweil]

The static code analyzer Coverity Scan reports 330 open issues (after #5995 is applied) for the current git master branch. A quick review of those issues shows that at least some of them are real bugs which must be fixed.

Therefore all issues should be reviewed and classified (Coverity Scan has classifications for bug, false positive, intentional and pending). Ideally bugs should also be fixed.

[stweil]

The estimated costs for the classification of all reported issues are a few days (low).

Fixing bugs ranges from low costs for trivial fixes, but can also require medium or even high costs for more complex bugs. Therefore I'd restrict this task to fixing trivial bugs and reporting all other bugs as issues on GitHub.

Ideally all remaining issues in Coverity Scan which were classified as bugs should contain references to GitHub issues.

[solth]

Votes: 8