This test checks that flags passed to the external linker with -extldflags through gc_linkopts are correctly combined with other flags passed through -extldflags.

go tool link only uses the last set of flags passed with -extldflags. If more than one set of flags is passed, the last set is passed to the external linker, and the rest are silently ignored.

go_binary and go_test should look for -extldflags in gc_linkopts and combine the flags into a single list passed to go tool link. This includes flags generated by the rules themselves.

This test checks this behavior by adding extra rpaths, which has an observable effect on a go_binary linked with the external linker. The shell script checks that these paths are present.