if pkg == "runtime" {
		xmkdirall(pathf("%s/pkg/include", goroot))
		// For use by assembly and C files.
		copyfile(pathf("%s/pkg/include/textflag.h", goroot),
			pathf("%s/src/runtime/textflag.h", goroot), 0)
		copyfile(pathf("%s/pkg/include/funcdata.h", goroot),
			pathf("%s/src/runtime/funcdata.h", goroot), 0)
		copyfile(pathf("%s/pkg/include/asm_ppc64x.h", goroot),
			pathf("%s/src/runtime/asm_ppc64x.h", goroot), 0)

// failMessage creates a nicely formatted error message when there is no result to show.
func failMessage(paths []string, symbol, method string) error {
	var b bytes.Buffer
	if len(paths) > 1 {
		b.WriteString("s")
	}
	b.WriteString(" ")
	for i, path := range paths {
		if i > 0 {
			b.WriteString(", ")
		}
		b.WriteString(path)
	}
	if method == "" {
		return fmt.Errorf("no symbol %s in package%s", symbol, &b)
	}

An import path can also name a package to be downloaded from
a remote repository. Run 'go help importpath' for details.

Every package in a program must have a unique import path.
By convention, this is arranged by starting each path with a
unique prefix that belongs to you. For example, paths used
internally at Google all begin with 'google', and paths

			r.path = resolveImportPath(path, parentPath, parentDir, parentRoot, parentIsStd)
		} else if mode&ResolveModule != 0 {
			r.path = moduleImportPath(path, parentPath, parentDir, parentRoot)
		}
		if r.path == "" {
			r.path = path
		}
		return r
	})
	// Invariant: r.path is set to the resolved import path. If the path cannot
	// be resolved, r.path is set to path, the source import path.

// examples).
//
// The Dir, Target, Shlib, Root, ConflictDir, and Export file paths
// are all absolute paths.
//
// By default, the lists GoFiles, CgoFiles, and so on hold names of files in Dir
// (that is, paths relative to Dir, not absolute paths).
// The generated files added when using the -compiled and -test flags
// are absolute paths referring to cached copies of generated Go source files.

func modkey(m module.Version) module.Version {
	return module.Version{Path: m.Path, Version: m.Version + "/go.mod"}
}

func suggestModulePath(path string) string {
	var m string

	i := len(path)
	for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9' || path[i-1] == '.') {
		i--
	}
	url := path[:i]
	url = strings.TrimSuffix(url, "/v")
	url = strings.TrimSuffix(url, "/")

		}
		// If the same package name was used by multiple packages, display the full path.
		if len(check.pkgPathMap[pkg.name]) > 1 {
			return strconv.Quote(pkg.path)
		}
		return pkg.name
	}
	return ""
}

// markImports recursively walks pkg and its imports, to record unique import
// paths in pkgPathMap.
func (check *Checker) markImports(pkg *Package) {
	if check.seenPkgMap[pkg] {
		return

		if i > 0 {
			prev := rootModules[i-1]
			if prev.Path > m.Path || (prev.Path == m.Path && gover.ModCompare(m.Path, prev.Version, m.Version) > 0) {
				panic(fmt.Sprintf("newRequirements called with unsorted roots: %v", rootModules))
			}
		}

		if v, ok := rs.maxRootVersion[m.Path]; ok && gover.ModCompare(m.Path, v, m.Version) >= 0 {
			continue
		}
		rs.maxRootVersion[m.Path] = m.Version
	}

// been called.
func Lookup(parentPath string, parentIsStd bool, path string) (dir, realPath string, err error) {
	if path == "" {
		panic("Lookup called with empty package path")
	}

	if parentIsStd {
		path = loaded.stdVendor(parentPath, path)
	}
	pkg, ok := loaded.pkgCache.Get(path)
	if !ok {
		// The loader should have found all the relevant paths.
		// There are a few exceptions, though:

			name, path = ct[0], ct[1]
		}
		paths[name] = append(paths[name], path)
	}

	defaultPath := paths[""]
	b.llvmSymbolizer, b.llvmSymbolizerFound = chooseExe([]string{"llvm-symbolizer"}, []string{}, append(paths["llvm-symbolizer"], defaultPath...))
	b.addr2line, b.addr2lineFound = chooseExe([]string{"addr2line"}, []string{"gaddr2line"}, append(paths["addr2line"], defaultPath...))