In addition to setting PERL_DESTRUCT_LEVEL=2 you should also set PERL_DEBUG=1 and PERL_VALGRIND=1.

Last year, I asked P5P about a valgrind memory leak I was seeing but noone responded. In my test case: 

PERL_DEBUG=1 PERL_VALGRIND=1 PERL_DESTRUCT_LEVEL=2
 valgrind --leak-check=full perl -e 'sub k {1}'

[download]
produced no memory leak report from valgrind, while: 
PERL_DEBUG=1 PERL_VALGRIND=1 PERL_DESTRUCT_LEVEL=2
 valgrind --leak-check=full perl -e 'sub k () {1}'

[download]
produced: 
==4943== Memcheck, a memory error detector for x86-linux.
==4943== Copyright (C) 2002-2005, and GNU GPL'd, by Julian Seward et a
+l.
==4943== Using valgrind-2.4.0, a program supervision framework for x86
+-linux.
==4943== Copyright (C) 2000-2005, and GNU GPL'd, by Julian Seward et a
+l.
==4943== For more details, rerun with: -v
==4943==
==4943==
==4943== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 17 from 
+1)
==4943== malloc/free: in use at exit: 3 bytes in 1 blocks.
==4943== malloc/free: 775 allocs, 774 frees, 84102 bytes allocated.
==4943== For counts of detected errors, rerun with: -v
==4943== searching for pointers to 1 not-freed blocks.
==4943== checked 282624 bytes.
==4943==
==4943== 3 bytes in 1 blocks are definitely lost in loss record 1 of 1
==4943==    at 0x1B909222: malloc (vg_replace_malloc.c:130)
==4943==    by 0x80C698C: Perl_safesysmalloc (util.c:78)
==4943==    by 0x80C8152: Perl_savepv (util.c:774)
==4943==    by 0x80A5AE6: Perl_newCONSTSUB (op.c:4554)
==4943==    by 0x80A4994: Perl_newATTRSUB (op.c:4305)
==4943==    by 0x8097207: Perl_yyparse (perly.y:364)
==4943==    by 0x806433E: S_parse_body (perl.c:1844)
==4943==    by 0x8062FBA: perl_parse (perl.c:1308)
==4943==    by 0x805F658: main (perlmain.c:96)
==4943==
==4943== LEAK SUMMARY:
==4943==    definitely lost: 3 bytes in 1 blocks.
==4943==      possibly lost: 0 bytes in 0 blocks.
==4943==    still reachable: 0 bytes in 0 blocks.
==4943==         suppressed: 0 bytes in 0 blocks.
==4943== Reachable blocks (those to which a pointer was found) are not
+ shown.
==4943== To see them, rerun with: --show-reachable=yes

[download]

BTW, I'm eager to improve my skills in this area, so if anyone knows some useful links, please let me know.

Update: At the time I wrote this, I didn't realise that functions containing an empty prototype are candidates for inlining (see "Constant Functions" section in perlsub for more details).

In reply to Re: Valgrind, Perl, and banishing leaks by eyepopslikeamosquito
in thread Valgrind, Perl, and banishing leaks by creamygoodness

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