Command gopack
Gopack is a variant of the Plan 9 ar tool. The original is documented at
http://plan9.bell-labs.com/magic/man2html/1/ar
It adds a special Go-specific section __.PKGDEF that collects all the Go type information from the files in the archive; that section is used by the compiler when importing the package during compilation.
Usage: gopack [uvnbailogS][mrxtdpq][P prefix] archive files ...
The new option 'g' causes gopack to maintain the __.PKGDEF section as files are added to the archive.
The new option 'S' forces gopack to mark the archive as safe.
The new option 'P' causes gopack to remove the given prefix from file names in the line number information in object files that are already stored in or added to the archive.