Hello folks. I am puzzled. I've been noticing a message from cpan that I don't remember seeing before; an example is below. I was seeing 17 build dirs and then I ran install for a couple more today, and it jumped to 19. Why and how is cpan doing this? I know it's necessary when a module being built/tested/installed has prerequisites but they seem to be hanging around long after they are necessary. Anyone? If you're in the know, kindly enlighten me.

Prepending blib/arch and blib/lib of 19 build dirs to PERL5LIB, reaching size 2952; for 'install'

perl is CygwinPerl 5.40.3
CPAN/cpan is v2.38

EDIT

I've attempted to answer the question for myself, see below. Only with partial success.

Nov 25, 2025 at 18:41 UTC

In reply to What is cpan (the installer) doing prepending all these directories to the PERL5LIB path? by Intrepid

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