Devel::Leak has two functions NoteSV and CheckSV.

NoteSV walks the perl internal table of allocated SVs (scalar values)
- (which actually contains arrays and hashes too), and records their
addresses in a table. It returns a count of these "things", and
stores a pointer to the table (which is obtained from the heap using
malloc()) in its argument.

CheckSV is passed argument which holds a pointer to a table created
by NoteSV. It re-walks the perl-internals and calls sv_dump() for
any "things" which did not exist when NoteSV was called. It returns
a count of the number of "things" now allocated.

Homepage:
https://metacpan.org/release/Devel-Leak
