perl5: updated to 5.26.2

5.26.2:

Security
[CVE-2018-6797] heap-buffer-overflow (WRITE of size 1) in S_regatom (regcomp.c)
A crafted regular expression could cause a heap buffer write overflow, with control over the bytes written.
[CVE-2018-6798] Heap-buffer-overflow in Perl__byte_dump_string (utf8.c)
Matching a crafted locale dependent regular expression could cause a heap buffer read overflow and potentially information disclosure.
[CVE-2018-6913] heap-buffer-overflow in S_pack_rec
pack() could cause a heap buffer write overflow with a large item count.
Assertion failure in Perl__core_swash_init (utf8.c)
Control characters in a supposed Unicode property name could cause perl to crash. This has been fixed.

Updated Modules and Pragmata
Module::CoreList has been upgraded from version 5.20170922_26 to 5.20180414_26.
PerlIO::via has been upgraded from version 0.16 to 0.17.
Term::ReadLine has been upgraded from version 1.16 to 1.17.
Unicode::UCD has been upgraded from version 0.68 to 0.69.

Selected Bug Fixes
The readpipe() built-in function now checks at compile time that it has only one parameter expression, and puts it in scalar context, thus ensuring that it doesn't corrupt the stack at runtime.
Fixed a use after free bug in pp_list introduced in Perl 5.27.1.
Parsing a sub definition could cause a use after free if the sub keyword was followed by whitespace including newlines (and comments).
The tokenizer now correctly adjusts a parse pointer when skipping whitespace in an ${identifier} construct.
Accesses to ${^LAST_FH} no longer assert after using any of a variety of I/O operations on a non-glob.
sort now performs correct reference counting when aliasing $a and $b, thus avoiding premature destruction and leakage of scalars if they are re-aliased during execution of the sort comparator.
Some convoluted kinds of regexp no longer cause an arithmetic overflow when compiled.
Fixed a duplicate symbol failure with -flto -mieee-fp builds. pp.c defined _LIB_VERSION which -lieee already defines.
A NULL pointer dereference in the S_regmatch() function has been fixed.
Failures while compiling code within other constructs, such as with string interpolation and the right part of s///e now cause compilation to abort earlier.

(adam)