Libelektra: c99 build

[ingwinlu]

After #2063 is in I would like to add a new build job with the following properties:

• [ ] set -std=c99
• [x] add -Werror

It should check if Elektra properly disables plugins/bindings/... when standards are not met.

I started work on the patches in https://github.com/ingwinlu/libelektra/tree/fix_non_c99_errors

[markus2330]

@sanssecours Is this already fixed?

[sanssecours]

Is this already fixed?

Not as far as I can know. I do not think we have a build job that uses -std=c99 yet.

[markus2330]

And the -Werror?

[sanssecours]

And the -Werror?

The only build job that does not use -Werror is debian-oldstable-full.

[markus2330]

I think we went already quite far with this.