Re^3: What is "double free or corruption"?

Does this reveal anything useful?

[root@eco ~]# ltrace perl -MCPAN -e shell
__libc_start_main(0x8049278, 4, 0xbfffe644, 0x804a55c, 0x804a5b0 <unfi
+nished ...>
signal(8, 0x1)                                                        
+= NULL
{ lots of stuff} 

cpan shell -- CPAN exploration and modules installation (v1.7601)
ReadLine support enabled

cpan> q
<... perl_run resumed> )                                              
+= 0
perl_destruct(0x804bc10, 0x80493b8, 4, 0xbfffe644, 0Lockfile removed.
*** glibc detected *** double free or corruption: 0x08610b28 ***
 <unfinished ...>
--- SIGABRT (Aborted) ---
+++ killed by SIGABRT +++
[root@eco ~]#
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Comment on Re^3: What is "double free or corruption"? Download Code

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Re^4: What is "double free or corruption"? by gaal (Parson) on Sep 17, 2004 at 14:56 UTC
Looks like it's happening, surprise, during global destruction. My practical knowledge ends here :) But generally I suppose what you want is to mark all your variables so that when you trip the warning you know who it is who's freeing 0x08610b28 (and what 0x08610b28 is). (Obvisouly it can be a different value next time round!) I know GTK has a switch to make warnings fatal, so that if you run a process in gdb you are dropped into the debugger and have a stack trace at your disposal. Probably glibc has something similar? You'll likely need the debug version of your libraries for this.	[reply]

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Re^4: What is "double free or corruption"?
by gaal (Parson) on Sep 17, 2004 at 14:56 UTC

I know GTK has a switch to make warnings fatal, so that if you run a process in gdb you are dropped into the debugger and have a stack trace at your disposal. Probably glibc has something similar? You'll likely need the debug version of your libraries for this.

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