8 files changed, 16 insertions, 95 deletions
diff --git a/src/cmd/compile/internal/gc/bootstrap.go b/src/cmd/compile/internal/gc/bootstrap.go
deleted file mode 100644
index 37b0d59ede..0000000000
--- a/src/cmd/compile/internal/gc/bootstrap.go
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !go1.8
-// +build !go1.8
-
-package gc
-
-import (
-	"cmd/compile/internal/base"
-	"runtime"
-)
-
-func startMutexProfiling() {
-	base.Fatalf("mutex profiling unavailable in version %v", runtime.Version())
-}
diff --git a/src/cmd/compile/internal/gc/pprof.go b/src/cmd/compile/internal/gc/pprof.go
deleted file mode 100644
index 5f9b030621..0000000000
--- a/src/cmd/compile/internal/gc/pprof.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build go1.8
-// +build go1.8
-
-package gc
-
-import "runtime"
-
-func startMutexProfiling() {
-	runtime.SetMutexProfileFraction(1)
-}
diff --git a/src/cmd/compile/internal/gc/trace.go b/src/cmd/compile/internal/gc/trace.go
deleted file mode 100644
index 8cdbd4b0f3..0000000000
--- a/src/cmd/compile/internal/gc/trace.go
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build go1.7
-// +build go1.7
-
-package gc
-
-import (
-	"os"
-	tracepkg "runtime/trace"
-
-	"cmd/compile/internal/base"
-)
-
-func init() {
-	traceHandler = traceHandlerGo17
-}
-
-func traceHandlerGo17(traceprofile string) {
-	f, err := os.Create(traceprofile)
-	if err != nil {
-		base.Fatalf("%v", err)
-	}
-	if err := tracepkg.Start(f); err != nil {
-		base.Fatalf("%v", err)
-	}
-	base.AtExit(tracepkg.Stop)
-}
diff --git a/src/cmd/compile/internal/gc/util.go b/src/cmd/compile/internal/gc/util.go
index 56fd137de2..dcac0ce79a 100644
--- a/src/cmd/compile/internal/gc/util.go
+++ b/src/cmd/compile/internal/gc/util.go
@@ -8,12 +8,11 @@ import (
 	"os"
 	"runtime"
 	"runtime/pprof"
+	tracepkg "runtime/trace"
 
 	"cmd/compile/internal/base"
 )
 
-var traceHandler func(string)
-
 func startProfile() {
 	if base.Flag.CPUProfile != "" {
 		f, err := os.Create(base.Flag.CPUProfile)
@@ -64,13 +63,20 @@ func startProfile() {
 		if err != nil {
 			base.Fatalf("%v", err)
 		}
-		startMutexProfiling()
+		runtime.SetMutexProfileFraction(1)
 		base.AtExit(func() {
 			pprof.Lookup("mutex").WriteTo(f, 0)
 			f.Close()
 		})
 	}
-	if base.Flag.TraceProfile != "" && traceHandler != nil {
-		traceHandler(base.Flag.TraceProfile)
+	if base.Flag.TraceProfile != "" {
+		f, err := os.Create(base.Flag.TraceProfile)
+		if err != nil {
+			base.Fatalf("%v", err)
+		}
+		if err := tracepkg.Start(f); err != nil {
+			base.Fatalf("%v", err)
+		}
+		base.AtExit(tracepkg.Stop)
 	}
 }
diff --git a/src/cmd/compile/internal/logopt/escape.go b/src/cmd/compile/internal/logopt/escape.go
deleted file mode 100644
index 9660e938b4..0000000000
--- a/src/cmd/compile/internal/logopt/escape.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build go1.8
-// +build go1.8
-
-package logopt
-
-import "net/url"
-
-func pathEscape(s string) string {
-	return url.PathEscape(s)
-}
diff --git a/src/cmd/compile/internal/logopt/escape_bootstrap.go b/src/cmd/compile/internal/logopt/escape_bootstrap.go
deleted file mode 100644
index cc04eaadfd..0000000000
--- a/src/cmd/compile/internal/logopt/escape_bootstrap.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !go1.8
-// +build !go1.8
-
-package logopt
-
-// For bootstrapping with an early version of Go
-func pathEscape(s string) string {
-	panic("This should never be called; the compiler is not fully bootstrapped if it is.")
-}
diff --git a/src/cmd/compile/internal/logopt/log_opts.go b/src/cmd/compile/internal/logopt/log_opts.go
index 9fee83426f..09825e8278 100644
--- a/src/cmd/compile/internal/logopt/log_opts.go
+++ b/src/cmd/compile/internal/logopt/log_opts.go
@@ -376,7 +376,7 @@ func writerForLSP(subdirpath, file string) io.WriteCloser {
 	if lastdot != -1 {
 		basename = basename[:lastdot]
 	}
-	basename = pathEscape(basename)
+	basename = url.PathEscape(basename)
 
 	// Assume a directory, make a file
 	p := filepath.Join(subdirpath, basename+".json")
@@ -428,7 +428,7 @@ func FlushLoggedOpts(ctxt *obj.Link, slashPkgPath string) {
 		if slashPkgPath == "" {
 			slashPkgPath = "\000"
 		}
-		subdirpath := filepath.Join(dest, pathEscape(slashPkgPath))
+		subdirpath := filepath.Join(dest, url.PathEscape(slashPkgPath))
 		err := os.MkdirAll(subdirpath, 0755)
 		if err != nil {
 			log.Fatalf("Could not create directory %s for logging optimizer actions, %v", subdirpath, err)
diff --git a/src/cmd/compile/internal/noder/stencil.go b/src/cmd/compile/internal/noder/stencil.go
index 280f7cdf1c..d3f51e00cd 100644
--- a/src/cmd/compile/internal/noder/stencil.go
+++ b/src/cmd/compile/internal/noder/stencil.go
@@ -1357,6 +1357,9 @@ func (g *genInst) dictPass(info *instInfo) {
 			}
 		case ir.ODOTTYPE, ir.ODOTTYPE2:
 			dt := m.(*ir.TypeAssertExpr)
+			if dt.Type().IsEmptyInterface() || (dt.Type().IsInterface() && !dt.Type().HasShape()) {
+				break
+			}
 			if !dt.Type().HasShape() && !(dt.X.Type().HasShape() && !dt.X.Type().IsEmptyInterface()) {
 				break
 			}