brew remove inkscape : Error: Calling needs :cxx11 is disabled

Both the taps caskformula/caskformula and weikengchen/caskformula (possibly others?) seem to cause this problem. To list your current taps, run

brew tap

Now untap the suspicious repository:

brew untap caskformula/caskformula # This worked for me

Run brew doctor to check for issues after removing caskformula. If there are issues, follow the recommendations.

Finally update repositories and upgrade software:

brew update

brew upgrade

Some more info in this issue on github:

https://github.com/caskformula/homebrew-caskformula/issues/74

This finally fixed my problem:

brew untap weikengchen/caskformula
brew update && brew upgrade