"cmd/go/internal/fsys"
	"cmd/go/internal/load"
	"cmd/go/internal/str"
	"cmd/internal/pkgpath"
)

// The Gccgo toolchain.

type gccgoToolchain struct{}

var GccgoName, GccgoBin string
var gccgoErr error

func init() {
	GccgoName = cfg.Getenv("GCCGO")
	if GccgoName == "" {
		GccgoName = "gccgo"
	}
	GccgoBin, gccgoErr = cfg.LookPath(GccgoName)
}

func (gccgoToolchain) compiler() string {

				// Fake packages - nothing to build.
				a.Mode = "built-in package"
				a.Actor = nil
				return a
			}

			// gccgo standard library is "fake" too.
			if cfg.BuildToolchainName == "gccgo" {
				// the target name is needed for cgo.
				a.Mode = "gccgo stdlib"
				a.Target = p.Target
				a.Actor = nil
				return a
			}
		}

		return a
	})

	"C_INCLUDE_PATH",     // allow override non-standard include paths
	"CC",                 // don't lose user settings when invoking cgo
	"GO_TESTING_GOTOOLS", // for gccgo testing
	"GCCGO",              // for gccgo testing
	"GCCGOTOOLDIR",       // for gccgo testing
}

// updateSum runs 'go mod tidy', 'go list -mod=mod -m all', or
// 'go list -mod=mod all' in the test's current directory if a file named

			// path is a resolved package path, not an import path.
			file, ok := cfg.PackageFile[path]
			if !ok {
				if cfg.Compiler == "gccgo" && cfg.Standard[path] {
					return nil, nil // fall back to default gccgo lookup
				}
				return nil, fmt.Errorf("no package file for %q", path)
			}
			return os.Open(file)
		})

	"internal/goversion",
	// internal/lazyregexp is provided by Go 1.17, which permits it to
	// be imported by other packages in this list, but is not provided
	// by the Go 1.17 version of gccgo. It's on this list only to
	// support gccgo, and can be removed if we require gccgo 14 or later.
	"internal/lazyregexp",
	"internal/pkgbits",
	"internal/platform",
	"internal/profile",
	"internal/race",
	"internal/saferio",
	"internal/syscall/unix",

	}

	// sanity check some often mis-used options
	switch cfg.BuildContext.Compiler {
	case "gccgo":
		if load.BuildGcflags.Present() {
			fmt.Println("go build: when using gccgo toolchain, please pass compiler flags using -gccgoflags, not -gcflags")
		}
		if load.BuildLdflags.Present() {
			fmt.Println("go build: when using gccgo toolchain, please pass linker flags using -gccgoflags, not -ldflags")
		}
	case "gc":

	GO111MODULE
		Controls whether the go command runs in module-aware mode or GOPATH mode.
		May be "off", "on", or "auto".
		See https://golang.org/ref/mod#mod-commands.
	GCCGO
		The gccgo command to run for 'go build -compiler=gccgo'.
	GOARCH
		The architecture, or processor, for which to compile code.
		Examples are amd64, 386, arm, ppc64.
	GOBIN
		The directory where 'go install' will install a command.
	GOCACHE

		env = os.Getenv("GOROOT")
	}
	if env != "" {
		return filepath.Clean(env)
	}
	def := ""
	if r := runtime.GOROOT(); r != "" {
		def = filepath.Clean(r)
	}
	if runtime.Compiler == "gccgo" {
		// gccgo has no real GOROOT, and it certainly doesn't
		// depend on the executable's location.
		return def
	}

	// canonical returns a directory path that represents
	// the same directory as dir,

	if err == nil {
		return mi.Package(relPath(pkgdir, modroot)), nil
	}
	if !errors.Is(err, errNotFromModuleCache) {
		return nil, err
	}
	if cfg.BuildContext.Compiler == "gccgo" && str.HasPathPrefix(modroot, cfg.GOROOTsrc) {
		return nil, err // gccgo has no sources for GOROOT packages.
	}
	return openIndexPackage(modroot, pkgdir)
}

// GetModule returns the Module for the given modroot.

		generated output.
	-gccgo
		Generate output for the gccgo compiler rather than the
		gc compiler.
	-gccgoprefix prefix
		The -fgo-prefix option to be used with gccgo.
	-gccgopkgpath path
		The -fgo-pkgpath option to be used with gccgo.
	-gccgo_define_cgoincomplete
		Define cgo.Incomplete locally rather than importing it from
		the "runtime/cgo" package. Used for old gccgo versions.
	-godefs