runtime: print more information on stack overflow
Print the current SP and (old) stack bounds when the stack grows
too large. This helps to identify the problem: whether a large
stack is used, or something else goes wrong.
For #35470.
Change-Id: I34a4064d5c7280978391d835e171b90d06f87222
Reviewed-on: https://go-review.googlesource.com/c/go/+/207351
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
diff --git a/src/runtime/crash_test.go b/src/runtime/crash_test.go
index 6c3127f..5333b60 100644
--- a/src/runtime/crash_test.go
+++ b/src/runtime/crash_test.go
@@ -204,9 +204,23 @@
func TestStackOverflow(t *testing.T) {
output := runTestProg(t, "testprog", "StackOverflow")
- want := "runtime: goroutine stack exceeds 1474560-byte limit\nfatal error: stack overflow"
- if !strings.HasPrefix(output, want) {
- t.Fatalf("output does not start with %q:\n%s", want, output)
+ want := []string{
+ "runtime: goroutine stack exceeds 1474560-byte limit\n",
+ "fatal error: stack overflow",
+ // information about the current SP and stack bounds
+ "runtime: sp=",
+ "stack=[",
+ }
+ if !strings.HasPrefix(output, want[0]) {
+ t.Errorf("output does not start with %q", want[0])
+ }
+ for _, s := range want[1:] {
+ if !strings.Contains(output, s) {
+ t.Errorf("output does not contain %q", s)
+ }
+ }
+ if t.Failed() {
+ t.Logf("output:\n%s", output)
}
}
diff --git a/src/runtime/stack.go b/src/runtime/stack.go
index 84fbd33..ebbe3e0 100644
--- a/src/runtime/stack.go
+++ b/src/runtime/stack.go
@@ -1030,6 +1030,7 @@
newsize := oldsize * 2
if newsize > maxstacksize {
print("runtime: goroutine stack exceeds ", maxstacksize, "-byte limit\n")
+ print("runtime: sp=", hex(sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n")
throw("stack overflow")
}
