==12066== Memcheck, a memory error detector
==12066== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==12066== Using Valgrind-3.16.1 and LibVEX; rerun with -h for copyright info
==12066== Command: perl -wc mx_segfault.pl
==12066== 
==12066== Invalid read of size 2
==12066==    at 0x251CCD: S_pop_eval_context_maybe_croak (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x25FFA0: Perl_pp_leaveeval (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x213312: Perl_runops_standard (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x177DFD: Perl_call_sv (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x17A70D: Perl_call_list (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x15E84A: S_process_special_blocks (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x170805: Perl_newATTRSUB_x (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x1743DA: Perl_utilize (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x1B000E: Perl_yyparse (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x17E836: perl_parse (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x155295: main (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==  Address 0x4c2528a is 314 bytes inside a block of size 1,872 free'd
==12066==    at 0x483AD7B: realloc (vg_replace_malloc.c:834)
==12066==    by 0x1F385C: Perl_safesysrealloc (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x24D3BB: Perl_cxinc (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x21CED4: Perl_pp_entersub (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x213312: Perl_runops_standard (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x25130B: S_docatch (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x213312: Perl_runops_standard (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x177C5A: Perl_call_sv (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x87D828C: call_after (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/lib/site_perl/5.36.0/x86_64-linux/auto/B/Hooks/AtRuntime/AtRuntime.so)
==12066==    by 0x24F7A1: Perl_leave_scope (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x251CCC: S_pop_eval_context_maybe_croak (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x25FFA0: Perl_pp_leaveeval (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==  Block was alloc'd at
==12066==    at 0x483877F: malloc (vg_replace_malloc.c:307)
==12066==    by 0x1F3502: Perl_safesysmalloc (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x24D316: Perl_new_stackinfo (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x15E9D6: S_process_special_blocks (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x170805: Perl_newATTRSUB_x (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x1743DA: Perl_utilize (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x1B000E: Perl_yyparse (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x17E836: perl_parse (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)
==12066==    by 0x155295: main (in /home/haj/perl5/perlbrew/perls/perl-5.36.0/bin/perl)