diff --git a/xpcom/ds/StickyTimeDuration.h b/xpcom/ds/StickyTimeDuration.h
index 750e813ea84..39a887dbce2 100644
--- a/xpcom/ds/StickyTimeDuration.h
+++ b/xpcom/ds/StickyTimeDuration.h
@@ -159,7 +159,7 @@ StickyTimeDurationValueCalculator::Multiply<int64_t>(int64_t aA,
   // return -Forever if the signs differ, or +Forever otherwise.
   if (aA == INT64_MAX || aA == INT64_MIN ||
       aB == INT64_MAX || aB == INT64_MIN) {
-    return (aA >= 0) ^ (aB >= 0) ? INT64_MAX : INT64_MIN;
+    return (aA >= 0) ^ (aB >= 0) ? INT64_MIN : INT64_MAX;
   }
 
   return aA * aB;
@@ -177,7 +177,7 @@ StickyTimeDurationValueCalculator::Multiply<double>(int64_t aA, double aB)
   // +/-Forever or +/-Infinity, then return -Forever if the signs differ,
   // or +Forever otherwise.
   if (aA == INT64_MAX || aA == INT64_MIN || IsInfinite(aB)) {
-    return (aA >= 0) ^ (aB >= 0.0) ? INT64_MAX : INT64_MIN;
+    return (aA >= 0) ^ (aB >= 0.0) ? INT64_MIN : INT64_MAX;
   }
 
   return aA * aB;