# the coverage report on MSWin32 will be different on Win10 from Ubuntu Linux. # I assume the OP would like to merge the two reports to make sure that all the # functions are covered at least once between the two (or more) different # environments if($^O eq 'MSWin32') { run_this_function(); } else { run_a_different_function(); } # or # the coverage report is different in the environment where # MY_ENV_VAR is set true vs where it's false or undefined, # and the OP would like to merge the two reports to make sure that all the # functions are covered at least once between the two (or more) different # environments if( $ENV{MY_ENV_VAR} ) { run_special_case(); } # different parts of the code are covered depending on whether some other # executable is found, so that it can be run if( -x '/x/y/bin/my_executable' ) { my $ret = qx(/x/y/bin/my_executable); # cannot run on system X, where repo is in /a/b/repo/run.pl, and /x/y/ hierarchy might not even exist! ... error processing ... $some_outer_variable += $ret; }