Package gcimporter implements Import for gc-generated object files.
FindExportData positions the reader r at the beginning of the export data section of an underlying GC-created object/archive file by reading from it. The reader must be positioned at the start of the file before calling this function. The hdr result is the string before the export data, either "$$" or "$$B".
FindPkg returns the filename and unique package id for an import path based on package information provided by build.Import (using the build.Default build.Context). A relative srcDir is interpreted relative to the current working directory. If no file was found, an empty filename is returned.
Import imports a gc-generated package given its import path and srcDir, adds the corresponding package object to the packages map, and returns the object. The packages map must contain all packages already imported.