rql #158948 Under windows, pip install crashes if no compiler is present [validation pending]

This should not happen as compiled extensions (which require the compiler) are optional.

prioritynormal
typebug
done in0.31.4
load0.100
load left0.000
closed by#679566d1203d [pkg] Make sure the gecode extension build never ever fails (closes #158948)
patch[setup] use a generic exception for extension compilation [folded][pkg] Make sure the gecode extension build never ever fails [applied]