Assertion `PL_valid_types_PVX[SvTYPE(_svpvx) & SVt_MASK]' failed

[p5pRT]

Migrated from rt.perl.org#134474 (status was 'new')

Searchable as RT134474$

[p5pRT]

From geeknik@protonmail.ch

While fuzzing Perl v5.31.4-273-ge55ec39201 compiled with Clang 10 and UBSan, the following assertion failure was observed.

./perl -e 'map2,map$$_[$_],@V_=nmap2,map$$A[$_],@V_=neeee'

perl: pp_hot.c:5387: SV *Perl_vivify_ref(SV *, U32): Assertion `PL_valid_types_PVX[SvTYPE(_svpvx) & SVt_MASK]' failed.
Aborted

[dur-randir]

Looks like stack-not-refcounted for me.

[jkeenan]

Failure confirmed on blead on Linux:

$ git describe
v5.31.11-7-gf50fa03b75
$ sh ./Configure -des -Dusedevel -DDEBUGGING -Dcc=clang && make
$ ./perl -e 'map2,map$$_[$_],@V_=nmap2,map$$A[$_],@V_=neeee'
perl: pp_hot.c:5433: SV *Perl_vivify_ref(SV *, U32): Assertion `PL_valid_types_PVX[SvTYPE(_svpvx) & SVt_MASK]' failed.
Aborted (core dumped)