func (a *addr2LinerJob) close() {
	a.in.Close()
	a.cmd.Wait()
}

// newAddr2Liner starts the given addr2liner command reporting
// information about the given executable file. If file is a shared
// library, base should be the address at which it was mapped in the
// program under consideration.
func newAddr2Liner(cmd, file string, base uint64) (*addr2Liner, error) {
	if cmd == "" {
		cmd = defaultAddr2line
	}

func (f *fileAddr2Line) init() {
	if llvmSymbolizer, err := newLLVMSymbolizer(f.b.llvmSymbolizer, f.name, f.base, f.isData); err == nil {
		f.llvmSymbolizer = llvmSymbolizer
		return
	}

	if addr2liner, err := newAddr2Liner(f.b.addr2line, f.name, f.base); err == nil {
		f.addr2liner = addr2liner

		// When addr2line encounters some gcc compiled binaries, it
		// drops interesting parts of names in anonymous namespaces.