cmd/compile: fix names of inlined methods from other packages

Previously, an inlined call to wg.Done() in package main would have the
following incorrect symbol name:

    main.(*sync.WaitGroup).Done

This change modifies methodname to return the correct symbol name:

    sync.(*WaitGroup).Done

This fix was suggested by @mdempsky.

Fixes #19467.

Change-Id: I0117838679ac5353789299c618ff8c326712d94d
Reviewed-on: https://go-review.googlesource.com/37866
Reviewed-by: Austin Clements <austin@google.com>

diff --git a/src/cmd/compile/internal/gc/dcl.go b/src/cmd/compile/internal/gc/dcl.go
index c58d615910ca6f5d5b2816aca70d8746a21c1e29..328a65dc0e14e2baeae50cb61e0249b7e6aa8291 100644 (file)
--- a/src/cmd/compile/internal/gc/dcl.go
+++ b/src/cmd/compile/internal/gc/dcl.go
@@ -1041,16 +1041,12 @@ func methodname(s *Sym, recv *Type) *Sym {
 
        var p string
        if star {
-               p = fmt.Sprintf("(*%v).%v", tsym, s)
+               p = fmt.Sprintf("(*%v).%v", tsym.Name, s)
        } else {
                p = fmt.Sprintf("%v.%v", tsym, s)
        }
 
-       if exportname(tsym.Name) {
-               s = lookup(p)
-       } else {
-               s = Pkglookup(p, tsym.Pkg)
-       }
+       s = Pkglookup(p, tsym.Pkg)
 
        return s
 }

diff --git a/test/fixedbugs/issue19467.dir/mysync.go b/test/fixedbugs/issue19467.dir/mysync.go
new file mode 100644 (file)
index 0000000..d0e6fe0
--- /dev/null
+++ b/test/fixedbugs/issue19467.dir/mysync.go
@@ -0,0 +1,21 @@
+// 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.
+
+package mysync
+
+import "runtime"
+
+type WaitGroup struct {
+       Callers []uintptr
+}
+
+func (wg *WaitGroup) Add(x int) {
+       wg.Callers = make([]uintptr, 32)
+       n := runtime.Callers(1, wg.Callers)
+       wg.Callers = wg.Callers[:n]
+}
+
+func (wg *WaitGroup) Done() {
+       wg.Add(-1)
+}

diff --git a/test/fixedbugs/issue19467.dir/z.go b/test/fixedbugs/issue19467.dir/z.go
new file mode 100644 (file)
index 0000000..d381103
--- /dev/null
+++ b/test/fixedbugs/issue19467.dir/z.go
@@ -0,0 +1,34 @@
+// 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.
+
+package main
+
+import (
+       "./mysync"
+       "log"
+       "runtime"
+)
+
+func main() {
+       var wg mysync.WaitGroup
+       wg.Done()
+       ci := runtime.CallersFrames(wg.Callers)
+       frames := make([]runtime.Frame, 0, 4)
+       for {
+               frame, more := ci.Next()
+               frames = append(frames, frame)
+               if !more {
+                       break
+               }
+       }
+       expecting := []string{
+               "mysync.(*WaitGroup).Add",
+               "mysync.(*WaitGroup).Done",
+       }
+       for i := 0; i < 2; i++ {
+               if frames[i].Function != expecting[i] {
+                       log.Fatalf("frame %d: got %s, want %s", i, frames[i].Function, expecting[i])
+               }
+       }
+}

diff --git a/test/fixedbugs/issue19467.go b/test/fixedbugs/issue19467.go
new file mode 100644 (file)
index 0000000..4212157
--- /dev/null
+++ b/test/fixedbugs/issue19467.go
@@ -0,0 +1,7 @@
+// rundir -l=4
+
+// 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.
+
+package ignored