runtime: skip gdb goroutine backtrace test on non-x86

Gdb is not able to backtrace our non-standard stack frames on RISC
architectures without frame pointer.

Change-Id: Id62a566ce2d743602ded2da22ff77b9ae34bc5ae
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/9456
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

diff --git a/src/runtime/runtime-gdb_test.go b/src/runtime/runtime-gdb_test.go
index d6d00035720155c60e798d23938320137e2acaeb..fe7d38a39c792679df2cf4b6681130404a50f249 100644 (file)
--- a/src/runtime/runtime-gdb_test.go
+++ b/src/runtime/runtime-gdb_test.go
@@ -64,7 +64,7 @@ func TestGdbPython(t *testing.T) {
                t.Fatalf("building source %v\n%s", err, out)
        }
 
-       got, _ := exec.Command("gdb", "-nx", "-q", "--batch", "-iex",
+       args := []string{"-nx", "-q", "--batch", "-iex",
                fmt.Sprintf("add-auto-load-safe-path %s/src/runtime", runtime.GOROOT()),
                "-ex", "br main.go:10",
                "-ex", "run",
@@ -79,11 +79,22 @@ func TestGdbPython(t *testing.T) {
                "-ex", "echo END\n",
                "-ex", "echo BEGIN print ptrvar\n",
                "-ex", "print ptrvar",
-               "-ex", "echo END\n",
-               "-ex", "echo BEGIN goroutine 2 bt\n",
-               "-ex", "goroutine 2 bt",
-               "-ex", "echo END\n",
-               filepath.Join(dir, "a.exe")).CombinedOutput()
+               "-ex", "echo END\n"}
+
+       // without framepointer, gdb cannot backtrace our non-standard
+       // stack frames on RISC architectures.
+       canBackTrace := false
+       switch runtime.GOARCH {
+       case "amd64", "386":
+               canBackTrace = true
+               args = append(args,
+                       "-ex", "echo BEGIN goroutine 2 bt\n",
+                       "-ex", "goroutine 2 bt",
+                       "-ex", "echo END\n")
+       }
+
+       args = append(args, filepath.Join(dir, "a.exe"))
+       got, _ := exec.Command("gdb", args...).CombinedOutput()
 
        firstLine := bytes.SplitN(got, []byte("\n"), 2)[0]
        if string(firstLine) != "Loading Go Runtime support." {
@@ -117,7 +128,9 @@ func TestGdbPython(t *testing.T) {
        }
 
        btGoroutineRe := regexp.MustCompile(`^#0\s+runtime.+at`)
-       if bl := blocks["goroutine 2 bt"]; !btGoroutineRe.MatchString(bl) {
+       if bl := blocks["goroutine 2 bt"]; canBackTrace && !btGoroutineRe.MatchString(bl) {
                t.Fatalf("goroutine 2 bt failed: %s", bl)
+       } else if !canBackTrace {
+               t.Logf("gdb cannot backtrace for GOARCH=%s, skipped goroutine backtrace test", runtime.GOARCH)
        }
 }