3 files changed, 37 insertions, 21 deletions

diff --git a/src/cmd/compile/internal/noder/decl.go b/src/cmd/compile/internal/noder/decl.go
index 40cbe50aff..375eb41898 100644
--- a/src/cmd/compile/internal/noder/decl.go
+++ b/src/cmd/compile/internal/noder/decl.go
@@ -46,7 +46,12 @@ func (g *irgen) importDecl(p *noder, decl *syntax.ImportDecl) {
 
 	g.pragmaFlags(decl.Pragma, 0)
 
-	ipkg := importfile(decl)
+	// Get the imported package's path, as resolved already by types2
+	// and gcimporter. This is the same path as would be computed by
+	// parseImportPath.
+	path := pkgNameOf(g.info, decl).Imported().Path()
+
+	ipkg := readImportFile(g.target, path)
 	if ipkg == ir.Pkgs.Unsafe {
 		p.importedUnsafe = true
 	}
@@ -55,6 +60,14 @@ func (g *irgen) importDecl(p *noder, decl *syntax.ImportDecl) {
 	}
 }
 
+// pkgNameOf returns the PkgName associated with the given ImportDecl.
+func pkgNameOf(info *types2.Info, decl *syntax.ImportDecl) *types2.PkgName {
+	if name := decl.LocalPkgName; name != nil {
+		return info.Defs[name].(*types2.PkgName)
+	}
+	return info.Implicits[decl].(*types2.PkgName)
+}
+
 func (g *irgen) constDecl(out *ir.Nodes, decl *syntax.ConstDecl) {
 	g.pragmaFlags(decl.Pragma, 0)
 
diff --git a/src/cmd/compile/internal/noder/import.go b/src/cmd/compile/internal/noder/import.go
index c4a57806eb..24d911ba38 100644
--- a/src/cmd/compile/internal/noder/import.go
+++ b/src/cmd/compile/internal/noder/import.go
@@ -175,36 +175,44 @@ func resolveImportPath(path string) (string, error) {
 	return path, nil
 }
 
-// TODO(mdempsky): Return an error instead.
 func importfile(decl *syntax.ImportDecl) *types.Pkg {
-	if decl.Path.Kind != syntax.StringLit {
-		base.Errorf("import path must be a string")
+	path, err := parseImportPath(decl.Path)
+	if err != nil {
+		base.Errorf("%s", err)
 		return nil
 	}
 
-	path, err := strconv.Unquote(decl.Path.Value)
-	if err != nil {
-		base.Errorf("import path must be a string")
-		return nil
+	pkg := readImportFile(typecheck.Target, path)
+	if pkg != ir.Pkgs.Unsafe && pkg.Height >= myheight {
+		myheight = pkg.Height + 1
 	}
+	return pkg
+}
 
-	if err := checkImportPath(path, false); err != nil {
-		base.Errorf("%s", err.Error())
-		return nil
+func parseImportPath(pathLit *syntax.BasicLit) (string, error) {
+	if pathLit.Kind != syntax.StringLit {
+		return "", errors.New("import path must be a string")
 	}
 
-	path, err = resolveImportPath(path)
+	path, err := strconv.Unquote(pathLit.Value)
 	if err != nil {
-		base.Errorf("%s", err)
-		return nil
+		return "", errors.New("import path must be a string")
+	}
+
+	if err := checkImportPath(path, false); err != nil {
+		return "", err
 	}
 
+	return resolveImportPath(path)
+}
+
+func readImportFile(target *ir.Package, path string) *types.Pkg {
 	importpkg := types.NewPkg(path, "")
 	if importpkg.Direct {
 		return importpkg // already fully loaded
 	}
 	importpkg.Direct = true
-	typecheck.Target.Imports = append(typecheck.Target.Imports, importpkg)
+	target.Imports = append(target.Imports, importpkg)
 
 	if path == "unsafe" {
 		return importpkg // initialized with universe
@@ -324,10 +332,6 @@ func importfile(decl *syntax.ImportDecl) *types.Pkg {
 		base.Ctxt.AddImport(file[len(file)-len(path)-len(".a"):], fingerprint)
 	}
 
-	if importpkg.Height >= myheight {
-		myheight = importpkg.Height + 1
-	}
-
 	return importpkg
 }
 
diff --git a/src/cmd/compile/internal/noder/irgen.go b/src/cmd/compile/internal/noder/irgen.go
index f02246111f..abaaa8cbb0 100644
--- a/src/cmd/compile/internal/noder/irgen.go
+++ b/src/cmd/compile/internal/noder/irgen.go
@@ -98,6 +98,7 @@ type irgen struct {
 
 func (g *irgen) generate(noders []*noder) {
 	types.LocalPkg.Name = g.self.Name()
+	types.LocalPkg.Height = g.self.Height()
 	typecheck.TypecheckAllowed = true
 
 	// Prevent size calculations until we set the underlying type
@@ -132,8 +133,6 @@ Outer:
 			}
 		}
 	}
-	assert(myheight == g.self.Height())
-	types.LocalPkg.Height = myheight
 
 	// 2. Process all package-block type declarations. As with imports,
 	// we need to make sure all types are properly instantiated before