System Information
Ubuntu 16.04 64 bit - Intel graphic card

Blender Version
Broken: Blender 2.78a Official. Hash : e8299c8

Short description of error

Blender crash during weight transfer selecting type "vertex mapping" at options from weight transfer box if the input object not have any face (only vertex)
You can make a workaround easy adding a simple face to the input data object.

Exact steps for others to reproduce the error
There is only two objects at scene:
A ) one with vertex groups and vertex points but no faces
B) one torus without any vertex group.

Then :
Select input info object A
Select B while selecting A (holding Shift) making it parent from selection.
Select weight paint mode
At weight paint tools ("T" panel) , select Transfer Weights
Then from transfer weights dialog, select "vertex Mapping", any option (well I not try every option but brokes with the first ones) . That produce the crash.
You can add one face or more to object A to bypass this problem.