cmd/compile: correctly parse //line filename:line where filename contains ':'

This was a regression from 1.7. See the issue for details.

Fixes #18149.

Change-Id: Ic8f5a35d14edf9254b1275400316cff7aff32a27
Reviewed-on: https://go-review.googlesource.com/33799
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/cmd/compile/internal/gc/noder.go b/src/cmd/compile/internal/gc/noder.go
index f9de48a08b2c9d2ddbda2f2eb83988cdc10a06d8..a501cb67b6f7fc4111d8559492b2008786d597d3 100644 (file)
--- a/src/cmd/compile/internal/gc/noder.go
+++ b/src/cmd/compile/internal/gc/noder.go
@@ -1022,13 +1022,14 @@ func (p *noder) error(err error) {
 func (p *noder) pragma(pos, line int, text string) syntax.Pragma {
        switch {
        case strings.HasPrefix(text, "line "):
-               i := strings.IndexByte(text, ':')
+               // Want to use LastIndexByte below but it's not defined in Go1.4 and bootstrap fails.
+               i := strings.LastIndex(text, ":") // look from right (Windows filenames may contain ':')
                if i < 0 {
                        break
                }
                n, err := strconv.Atoi(text[i+1:])
                if err != nil {
-                       // todo: make this an error instead? it is almost certainly a bug.
+                       // TODO: make this an error instead? it is almost certainly a bug.
                        break
                }
                if n > 1e8 {

diff --git a/test/fixedbugs/issue18149.go b/test/fixedbugs/issue18149.go
new file mode 100644 (file)
index 0000000..112cd52
--- /dev/null
+++ b/test/fixedbugs/issue18149.go
@@ -0,0 +1,33 @@
+// run
+
+// 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.
+
+// Verify that //line directives with filenames
+// containing ':' (Windows) are correctly parsed.
+// (For a related issue, see test/fixedbugs/bug305.go)
+
+package main
+
+import (
+       "fmt"
+       "runtime"
+)
+
+func check(file string, line int) {
+       _, f, l, ok := runtime.Caller(1)
+       if !ok {
+               panic("runtime.Caller(1) failed")
+       }
+       if f != file || l != line {
+               panic(fmt.Sprintf("got %s:%d; want %s:%d", f, l, file, line))
+       }
+}
+
+func main() {
+//line /foo/bar.go:123
+       check(`/foo/bar.go`, 123)
+//line c:/foo/bar.go:987
+       check(`c:/foo/bar.go`, 987)
+}