Re^2: XS Error: Segfault with B::HooksAtRuntime


No such thing as a small change
	PerlMonks

Re^2: XS Error: Segfault with B::HooksAtRuntime

by haj (Vicar)

on Aug 06, 2022 at 16:15 UTC ( [id://11145983]=note: print w/replies, xml )

Need Help??

in reply to Re: XS Error: Segfault with B::HooksAtRuntime
in thread XS Error: Segfault with B::HooksAtRuntime

I can't solve the problem, but that info turned out to be sufficient for me to guess where to poke. I can reproduce a segfault in just 7 lines of code.

File: mx_segfault.pl

use lib '.';
use Demo;
[download]

File: Demo.pm

package Demo;
use MooseX::Extended;
require Stuff;
[download]

File: Stuff.pm

package Stuff;
use MooseX::Extended;
[download]

With this code, perl -wc mx_segfault.pl segfaults, and valgrind throws a 455-line tantrum.

Comment on Re^2: XS Error: Segfault with B::HooksAtRuntime Select or Download Code

Replies are listed 'Best First'.
Re^3: XS Error: Segfault with B::HooksAtRuntime by dave_the_m (Monsignor) on Aug 06, 2022 at 18:31 UTC
In general terms, that valgrind output shows that the calling of a sub while running code via call_after() (which requires a new CXt_SUB context sub to be pushed) grows the context stack (by reallocating it). Sometime later when exiting a use/require, the Cxt_EVAL frame is accessed using the old context stack address (the smaller stack that was freed when a larger one was allocated). So maybe something is holding on to a context stack pointer when it shouldn't - either in core or XS. Dave.	[reply]
Re^3: XS Error: Segfault with B::HooksAtRuntime by Ovid (Cardinal) on Aug 06, 2022 at 16:44 UTC
That's fantastic! I also don't know how to fix this, but having a reproduceable bug is a great start. Cheers, Ovid Hire me for training or software development.	[reply]

In Section Seekers of Perl Wisdom

Domain Nodelet^?

www.com | www.net | www.org

Node Status^?

node history
Node Type: note [id://11145983]
help

Chatterbox^?

How do I use this? • Last hour • Other CB clients

Other Users^?

Others imbibing at the Monastery: (4)

As of 2024-04-16 06:45 GMT

Sections^?

Information^?

Find Nodes^?

Leftovers^?

Today I Learned

Voting Booth^?

No recent polls found