Tcl Source Code: View Ticket

Ticket UUID:	135804138e33ff05b89f06101008113c86156322
Title:	TclOO segmentation fault: direct call to a method called by the object destructor, and that deletes the object via [rename] before calling [next]
Type:	Bug	Version:
Submitter:	pooryorick	Created on:	2019-11-13 21:20:59
Subsystem:	35. TclOO Package	Assigned To:	sebres
Priority:	5 Medium	Severity:	Minor
Status:	Closed	Last Modified:	2019-11-14 19:36:01
Resolution:	Fixed	Closed By:	pooryorick
		Closed on:	2019-11-14 19:36:01
Description:	The following script results in a segmentation fault in core-8-6-branch: `oo::class create c1 { method m1 {} {} } oo::class create c2 { superclass c1 destructor { my m1 } method m1 {} { rename [self] {} next # nextto c1 } } c2 create obj1 obj1 m1`
User Comments:	sebres added on 2019-11-14 17:22:34: Fixed now in branch bug-135804138e... I had 2 variants to solve that. In the 1st variant the result of test-case oo-7.10 would be something like: `- delete c2::destructor delete no-self c1::m1 unreachable /c2::destructor no-self 1 {no next method implementation} + delete c2::destructor delete no-self c1::m1 unreachable /c2::destructor no-self c1::m1 unreachable 0 {}` So the "next" had successfully called "c1::m1" second time, so it had assumed that only context of object is deleted (not a class in the call chain) and all access to my/self etc would be prohibited anyway, but just because "c1::m1" behaves like a proc (without object context access) it were possible without any issue to call it second time. The interim decision was another variant (as it is currently implemented in branch bug-135804138e) is calling of "next" is impossible after object deletion - so it throws an error there. pooryorick added on 2019-11-14 09:43:25: The initial script is the wrong script. This is the correct script to reproduce the segmentation fault: `oo::class create c1 { method m1 {} {} } oo::class create c2 { superclass c1 destructor { my m1 } method m1 {} { rename [self] {} next } } c2 create obj1 obj1 m1` aku added on 2019-11-13 21:35:26: I suspect that the script should be: oo::class create c1 { method m1 {} {} } oo::class create c2 { superclass c1 destructor { my m1 } method m1 {} { my m2 next } method m2 {} { rename [self] {} } } c2 create obj1 obj1 m1 aku added on 2019-11-13 21:32:40: I do not see where/how `m2` is invoked. And it seems to be an incomplete method definition as well.