go/types: change local gotype command to use source importer

Also: Remove -gccgo flag (not supported after 1.5), minor
cleanups.

Change-Id: I625241b07b277ac50ff836e2230b7b285887d35e
Reviewed-on: https://go-review.googlesource.com/37654
Reviewed-by: Alan Donovan <adonovan@google.com>

diff --git a/src/go/types/gotype.go b/src/go/types/gotype.go
index 0a36c0808399cf236c29de6f0b73a0444f208c0f..b466fb9fb26f83a88f8fe11e5b43d555ba887c5b 100644 (file)
--- a/src/go/types/gotype.go
+++ b/src/go/types/gotype.go
@@ -21,6 +21,10 @@ package.
 Otherwise, each path must be the filename of Go file belonging to
 the same package.
 
+Imports are processed by importing directly from the source of
+imported packages (default), or by importing from compiled and
+installed packages (by setting -c to the respective compiler).
+
 Usage:
        gotype [flags] [path...]
 
@@ -32,11 +36,7 @@ The flags are:
        -v
                verbose mode
        -c
-               compiler used to compile packages (gc or gccgo); default: gc
-               (gotype based on Go1.5 and up only)
-       -gccgo
-               use gccimporter instead of gcimporter
-               (gotype based on Go1.4 and before only)
+               compiler used for installed packages (gc, gccgo, or source); default: source
 
 Debugging flags:
        -seq
@@ -90,7 +90,7 @@ var (
        allFiles  = flag.Bool("a", false, "use all (incl. _test.go) files when processing a directory")
        allErrors = flag.Bool("e", false, "report all errors (not just the first 10)")
        verbose   = flag.Bool("v", false, "verbose mode")
-       gccgo     = flag.Bool("gccgo", false, "use gccgoimporter instead of gcimporter")
+       compiler  = flag.String("c", "source", "compiler used for installed packages (gc, gccgo, or source)")
 
        // debugging support
        sequential    = flag.Bool("seq", false, "parse sequentially, rather than in parallel")
@@ -103,7 +103,6 @@ var (
        fset       = token.NewFileSet()
        errorCount = 0
        parserMode parser.Mode
-       sizes      types.Sizes
 )
 
 func initParserMode() {
@@ -118,18 +117,6 @@ func initParserMode() {
        }
 }
 
-func initSizes() {
-       wordSize := 8
-       maxAlign := 8
-       switch build.Default.GOARCH {
-       case "386", "arm":
-               wordSize = 4
-               maxAlign = 4
-               // add more cases as needed
-       }
-       sizes = &types.StdSizes{WordSize: int64(wordSize), MaxAlign: int64(maxAlign)}
-}
-
 func usage() {
        fmt.Fprintln(os.Stderr, "usage: gotype [flags] [path ...]")
        flag.PrintDefaults()
@@ -248,11 +235,9 @@ func getPkgFiles(args []string) ([]*ast.File, error) {
 }
 
 func checkPkgFiles(files []*ast.File) {
-       compiler := "gc"
-       if *gccgo {
-               compiler = "gccgo"
-       }
        type bailout struct{}
+
+       // if checkPkgFiles is called multiple times, set up conf only once
        conf := types.Config{
                FakeImportC: true,
                Error: func(err error) {
@@ -261,8 +246,8 @@ func checkPkgFiles(files []*ast.File) {
                        }
                        report(err)
                },
-               Importer: importer.For(compiler, nil),
-               Sizes:    sizes,
+               Importer: importer.For(*compiler, nil),
+               Sizes:    types.SizesFor(build.Default.GOARCH),
        }
 
        defer func() {
@@ -301,7 +286,6 @@ func main() {
                *sequential = true
        }
        initParserMode()
-       initSizes()
 
        start := time.Now()