Perhaps the following will be helpful:

use strict;
use warnings;

my $input = '-L/usr/local/lib -lmylib -lz';
$input =~ s!^-L(.+)\s+\K-l(.+)(?=\s+.+)!$1/$2.a!;

print $input;

[download]

Output:

-L/usr/local/lib /usr/local/lib/mylib.a -lz

[download]

The \K says to keep all to its left. Here's an explanation of the regex.

In reply to Re: Help combining two regex's into one by Kenosis
in thread Help combining two regex's into one by Anonymous Monk

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