[perl #124207] Perl_ck_stringify: Assertion `!((((kid)->op_sibling) ? (_Bool)1 : (_Bool)0))' failed (op.c:11148)

On Sun Mar 29 13:43:30 2015, brian.carpenter@gmail.com wrote:
> perl v5.21.7 (v5.21.6-602-ge9d2bd8) just fails like this: 
> 
> syntax error at test24-min line 1, near "0]"
> syntax error at test24-min line 1, near "${}"
> Execution of test24-min aborted due to compilation errors.

5.21.7 assrted for me too. I bisected with:

AFL_HARDEN=1 perl ../bisect.pl --start=v5.18.0  -DDEBUGGING -Dcc=afl-gcc -Doptimize=-O2\ -g --target=miniperl -e 'eval q/qq{@{0]}${}},{})/'

which produced:

bad - non-zero exit from ./miniperl -Ilib -e eval q/qq{@{0]}${}},{})/
73f4c4fe76492cf68c8a57ccae33a9a3e5a87206 is the first bad commit
commit 73f4c4fe76492cf68c8a57ccae33a9a3e5a87206
Author: Father Chrysostomos <sprout@cpan.org>
Date:   Sun Oct 12 08:10:41 2014 -0700

    Optimise "@_" to a single join
    
    instead of stringify(join(...)).

:100644 100644 b4176c78c2e28c85545bc01963c0d9453e200a9b 8231b871e400fce359fa074e21d494111f91714f M      embed.h
:040000 040000 b8386d4e64ab3a616fc0ded5c3377b1eea6dac3e 780fd754644492829b74143eee8be0a53b105fc7 M      lib
:100644 100644 f1cdc0a3d0bc88a93f83b2ec5aab804520ab83c1 1de26aedb5504abe8350ceaf8f2db6e1affa1031 M      op.c
:100644 100644 142c75e131db5fc370b0a0a14f4e14a952f04bd7 f555e91fbb267e407b2eee443cef08769dc1b711 M      opcode.h
:100644 100644 88449326f28315a7e47db975738fb7bd1b3a2d21 042316019c80bcc058b1d03569905e132ef7289d M      proto.h
:040000 040000 d31c2bc09d1c95902de74eaf20cf8e7de829e160 0a0b729f329896c64db99333400d55cd5614ab0d M      regen
:040000 040000 d751917c2702ec4dce32a9bca1b4a7b7cefd4507 4079a6297b0ecc81e8948c662aaf422255b31854 M      t
bisect run success

Tony

---
via perlbug:  queue: perl5 status: new
https://rt.perl.org/Ticket/Display.html?id=124207

• [perl #124207] Perl_ck_stringify: Assertion `!((((kid)->op_sibling) ? (_Bool)1 : (_Bool)0))' failed (op.c:11148) by Tony Cook via RT
• Re: [perl #124207] Perl_ck_stringify: Assertion`!((((kid)->op_sibling) ? (_Bool)1 : (_Bool)0))' failed (op.c:11148) by Dave Mitchell