Fix crashes when trying to evaluate an expression and the type isn't known.
Fix crashes when trying to evaluate an expression and the type isn't known.

kleintom/dxr,srenatus/dxr,srenatus/dxr,nrc/dxr,pelmers/dxr,jbradberry/dxr,kleintom/dxr,bozzmob/dxr,jay-z007/dxr,pombredanne/dxr,KiemVM/Mozilla--dxr,gartung/dxr,erikrose/dxr,KiemVM/Mozilla--dxr,nrc/dxr,bozzmob/dxr,srenatus/dxr,jay-z007/dxr,srenatus/dxr,erikrose/dxr,srenatus/dxr,jbradberry/dxr,srenatus/dxr,pombredanne/dxr,bozzmob/dxr,pombredanne/dxr,jbradberry/dxr,nrc/dxr,KiemVM/Mozilla--dxr,nrc/dxr,kleintom/dxr,pombredanne/dxr,jay-z007/dxr,erikrose/dxr,pelmers/dxr,KiemVM/Mozilla--dxr,kleintom/dxr,jbradberry/dxr,jbradberry/dxr,pelmers/dxr,gartung/dxr,pelmers/dxr,jay-z007/dxr,gartung/dxr,bozzmob/dxr,jay-z007/dxr,bozzmob/dxr,gartung/dxr,gartung/dxr,gartung/dxr,erikrose/dxr,nrc/dxr,jbradberry/dxr,pelmers/dxr,pombredanne/dxr,pombredanne/dxr,pelmers/dxr,kleintom/dxr,nrc/dxr,pombredanne/dxr,gartung/dxr,jbradberry/dxr,bozzmob/dxr,kleintom/dxr,KiemVM/Mozilla--dxr,erikrose/dxr,kleintom/dxr,KiemVM/Mozilla--dxr,jay-z007/dxr,jay-z007/dxr,bozzmob/dxr,pelmers/dxr