Tcl Source Code: View Ticket

Description:
The following script causes a segmentation fault `proc dying {_ args} { puts [list $_ is dying] } oo::define oo::class {export createWithNamespace} oo::class createWithNamespace obj1 obj1 ::oo::define obj1 {self mixin [self]} ::oo::copy obj1 obj2 ::oo::objdefine obj2 {mixin [self]} ::oo::copy obj2 obj3 trace add command obj3 delete [list obj3 dying] rename obj2 {}`
User Comments:
pooryorick added on 2017-11-01 20:57:39: The problem lies in TclOO.c/ReleaseClassContents(), in a section that seems to be about removing a class that has been mixed into one of its instances (an unusual use case, to say the least): `for(j=0 ; j<instancePtr->mixins.num ; j++) { Class *mixin = instancePtr->mixins.list[j]; if (mixin == clsPtr) { instancePtr->mixins.list[j] = NULL; } }` Leaving a `NULL in the list breaks expectations. Instead, that particular item should be unstitched from the list.` pooryorick added on 2017-11-17 23:06:36: Fixed in commit [5f178e7f03].