Hi

I've tried what you suggested (manually installing rather than with cpan). List::MoreUtils required List::MoreUtils::XS so I tried to install that first. The "make test" immediately started spewing out these messages:

"/home/rg8239/perl/bin/perl" -MExtUtils::Command::MM -e 'cp_nonempty' 
+-- XS.bs blib/arch/auto/List/MoreUtils/XS/XS.bs 644

PERL_DL_NONLAZY=1 "/home/rg8239/perl/bin/perl" "-MExtUtils::Command::M
+M" "-MTest::Harness" "-e" "undef *Test::Harness::Switches; tes

t_harness(0, 'blib/lib', 'blib/arch')" t/*.t t/xs/*.t xt/*.t

XS.c: loadable library and perl binaries are mismatched (got handshake
+ key 0xc100000, needed 0xc180000)

t/xs/after.t ................

Dubious, test returned 1 (wstat 256, 0x100)

No subtests run
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so the problem is not with cpan.

You asked about the gcc compiler. It's the same compiler I had used to build 5.20. Also you mentioned the initial perl 5.30.3 installation running flawlessly. Well, pretty close to flawlessly--99.92%...

Failed 2 tests out of 2452, 99.92% okay.

        ../cpan/IO-Socket-IP/t/31nonblocking-connect-internet.t

        ../ext/POSIX/t/math.t
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the IO::Socket installed and is perfectly usable. The test failed because of a pretty restrictive proxy. The 5.20 install had the exact same test fails but I've had no issues with List::MoreUtils or any other modules so I'm not thinking the math test posed a major problem either