1 files changed, 21 insertions, 8 deletions
diff --git a/src/runtime/synctest.go b/src/runtime/synctest.go
index 08a0e5d444..16af1209b4 100644
--- a/src/runtime/synctest.go
+++ b/src/runtime/synctest.go
@@ -363,6 +363,13 @@ type specialBubble struct {
 	bubbleid uint64
 }
 
+// Keep these in sync with internal/synctest.
+const (
+	bubbleAssocUnbubbled     = iota // not associated with any bubble
+	bubbleAssocCurrentBubble        // associated with the current bubble
+	bubbleAssocOtherBubble          // associated with a different bubble
+)
+
 // getOrSetBubbleSpecial checks the special record for p's bubble membership.
 //
 // If add is true and p is not associated with any bubble,
@@ -371,10 +378,12 @@ type specialBubble struct {
 // It returns ok==true if p is associated with bubbleid
 // (including if a new association was added),
 // and ok==false if not.
-func getOrSetBubbleSpecial(p unsafe.Pointer, bubbleid uint64, add bool) (ok bool) {
+func getOrSetBubbleSpecial(p unsafe.Pointer, bubbleid uint64, add bool) (assoc int) {
 	span := spanOfHeap(uintptr(p))
 	if span == nil {
-		throw("getOrSetBubbleSpecial on invalid pointer")
+		// This is probably a package var.
+		// We can't attach a special to it, so always consider it unbubbled.
+		return bubbleAssocUnbubbled
 	}
 
 	// Ensure that the span is swept.
@@ -393,7 +402,11 @@ func getOrSetBubbleSpecial(p unsafe.Pointer, bubbleid uint64, add bool) (ok bool
 		// p is already associated with a bubble.
 		// Return true iff it's the same bubble.
 		s := (*specialBubble)((unsafe.Pointer)(*iter))
-		ok = s.bubbleid == bubbleid
+		if s.bubbleid == bubbleid {
+			assoc = bubbleAssocCurrentBubble
+		} else {
+			assoc = bubbleAssocOtherBubble
+		}
 	} else if add {
 		// p is not associated with a bubble,
 		// and we've been asked to add an association.
@@ -404,23 +417,23 @@ func getOrSetBubbleSpecial(p unsafe.Pointer, bubbleid uint64, add bool) (ok bool
 		s.special.next = *iter
 		*iter = (*special)(unsafe.Pointer(s))
 		spanHasSpecials(span)
-		ok = true
+		assoc = bubbleAssocCurrentBubble
 	} else {
 		// p is not associated with a bubble.
-		ok = false
+		assoc = bubbleAssocUnbubbled
 	}
 
 	unlock(&span.speciallock)
 	releasem(mp)
 
-	return ok
+	return assoc
 }
 
 // synctest_associate associates p with the current bubble.
 // It returns false if p is already associated with a different bubble.
 //
 //go:linkname synctest_associate internal/synctest.associate
-func synctest_associate(p unsafe.Pointer) (ok bool) {
+func synctest_associate(p unsafe.Pointer) int {
 	return getOrSetBubbleSpecial(p, getg().bubble.id, true)
 }
 
@@ -435,5 +448,5 @@ func synctest_disassociate(p unsafe.Pointer) {
 //
 //go:linkname synctest_isAssociated internal/synctest.isAssociated
 func synctest_isAssociated(p unsafe.Pointer) bool {
-	return getOrSetBubbleSpecial(p, getg().bubble.id, false)
+	return getOrSetBubbleSpecial(p, getg().bubble.id, false) == bubbleAssocCurrentBubble
 }