}
	if cfg.BuildMod == "vendor" {
		// Even if the main module is in the module cache,
		// its vendored dependencies are not loaded from their
		// usual cached locations.
		return nil, errNotFromModuleCache
	}
	modroot = filepath.Clean(modroot)
	if str.HasFilePathPrefix(modroot, cfg.GOROOTsrc) || !str.HasFilePathPrefix(modroot, cfg.GOMODCACHE) {
		return nil, errNotFromModuleCache
	}

					return module.Version{}, MainModules.ModRoot(mainModule), dir, nil, err
				} else if ok {
					return mainModule, MainModules.ModRoot(mainModule), dir, nil, nil
				}
			}
		}
		dir := filepath.Join(cfg.GOROOTsrc, path)
		modroot = cfg.GOROOTsrc
		if str.HasPathPrefix(path, "cmd") {
			modroot = filepath.Join(cfg.GOROOTsrc, "cmd")
		}

	os.Setenv("PWD", altRoot)
	goCmd(nil, "build", "-buildmode=plugin", "-o", filepath.Join(modRoot, "plugin-mismatch.so"), "./plugin-mismatch")

	os.Setenv("GOPATH", GOPATH)
	if err := os.Chdir(modRoot); err != nil {
		log.Panic(err)
	} else {
		prettyPrintf("cd %s\n", modRoot)
	}
	os.Setenv("PWD", modRoot)

	os.Setenv("LD_LIBRARY_PATH", modRoot)

	goCmd(nil, "build", "-buildmode=plugin", "./plugin1")

				modRoot := MainModules.ModRoot(v)
				if foundModRoot != "" && foundFrom != from && found != r {
					base.Errorf("conflicting replacements found for %v in workspace modules defined by %v and %v",
						mod, modFilePath(foundModRoot), modFilePath(modRoot))
					return found, foundModRoot, modFilePath(foundModRoot)
				}
				found, foundModRoot = r, modRoot
			}
		}
	}

		}
		if v, ok := rawGoVersion.Load(m); ok {
			info.GoVersion = v.(string)
		} else {
			panic("internal error: GoVersion not set for main module")
		}
		if modRoot := MainModules.ModRoot(m); modRoot != "" {
			info.Dir = modRoot
			info.GoMod = modFilePath(modRoot)
		}
		return info
	}

	info := &modinfo.ModulePublic{
		Path:     m.Path,
		Version:  m.Version,
		Indirect: rs != nil && !rs.direct[m.Path],

func cloneTestdataModule(gopath string) (string, error) {
	modRoot := filepath.Join(gopath, "src", "testshared")
	if err := cgotest.OverlayDir(modRoot, "testdata"); err != nil {
		return "", err
	}
	if err := os.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module testshared\n"), 0644); err != nil {
		return "", err
	}
	return modRoot, nil
}

		log.Panic(err)
	}
	defer os.RemoveAll(GOPATH)
	os.Setenv("GOPATH", GOPATH)

	modRoot := filepath.Join(GOPATH, "src", "testcshared")
	if err := cgotest.OverlayDir(modRoot, "testdata"); err != nil {
		log.Panic(err)
	}
	if err := os.Chdir(modRoot); err != nil {
		log.Panic(err)
	}
	os.Setenv("PWD", modRoot)
	if err := os.WriteFile("go.mod", []byte("module testcshared\n"), 0666); err != nil {
		log.Panic(err)

	if len(modRoots) > 1 {
		abs, err := filepath.Abs(dir)
		if err != nil {
			m.AddError(err)
			return
		}
		var found bool
		for _, modRoot := range modRoots {
			if modRoot != "" && str.HasFilePathPrefix(abs, modRoot) {
				found = true
			}
		}
		if !found {
			plural := ""
			if len(modRoots) > 1 {
				plural = "s"
			}

	// Copy testdata into GOPATH/src/testarchive, along with a go.mod file
	// declaring the same path.
	modRoot := filepath.Join(GOPATH, "src", "testcarchive")
	if err := cgotest.OverlayDir(modRoot, "testdata"); err != nil {
		log.Panic(err)
	}
	if err := os.Chdir(modRoot); err != nil {
		log.Panic(err)
	}
	os.Setenv("PWD", modRoot)
	if err := os.WriteFile("go.mod", []byte("module testcarchive\n"), 0666); err != nil {
		log.Panic(err)
	}