This is an internal method that returns path to a library which should be put on the linker command line after the external libraries to be linked to dynamic extensions. This may be needed if the linker is one-pass, and Perl includes some overrides for C RTL functions, such as malloc().
ExtUtils::MM_OS2 - methods to override UN*X behaviour in ExtUtils::MakeMaker
use ExtUtils::MM_OS2; # Done internally by ExtUtils::MakeMaker if needed
See ExtUtils::MM_Unix for a documentation of the methods provided there. This package overrides the implementation of these methods, not the semantics.