diff --git a/js/public/SliceBudget.h b/js/public/SliceBudget.h
index cea1f571eeb4..46c27392e830 100644
--- a/js/public/SliceBudget.h
+++ b/js/public/SliceBudget.h
@@ -37,7 +37,12 @@ struct JS_PUBLIC_API(WorkBudget)
  */
 class JS_PUBLIC_API(SliceBudget)
 {
-    static const mozilla::TimeStamp unlimitedDeadline;
+    const mozilla::TimeStamp &UnlimitedDeadline() const {
+        static const mozilla::TimeStamp unlimitedDeadline =
+            mozilla::TimeStamp::Now() + mozilla::TimeDuration::Forever();
+        return unlimitedDeadline;
+    }
+
     static const intptr_t unlimitedStartCounter = INTPTR_MAX;
 
     bool checkOverBudget();
@@ -69,7 +74,7 @@ class JS_PUBLIC_API(SliceBudget)
     explicit SliceBudget(WorkBudget work);
 
     void makeUnlimited() {
-        deadline = unlimitedDeadline;
+        deadline = UnlimitedDeadline();
         counter = unlimitedStartCounter;
     }
 
@@ -85,7 +90,7 @@ class JS_PUBLIC_API(SliceBudget)
 
     bool isWorkBudget() const { return deadline.IsNull(); }
     bool isTimeBudget() const { return !deadline.IsNull() && !isUnlimited(); }
-    bool isUnlimited() const { return deadline == unlimitedDeadline; }
+    bool isUnlimited() const { return deadline == UnlimitedDeadline(); }
 
     int describe(char* buffer, size_t maxlen) const;
 };
diff --git a/js/src/gc/GC.cpp b/js/src/gc/GC.cpp
index e52322947258..8b20f72e0e5a 100644
--- a/js/src/gc/GC.cpp
+++ b/js/src/gc/GC.cpp
@@ -305,7 +305,7 @@ namespace TuningDefaults {
     static const bool DynamicHeapGrowthEnabled = false;
 
     /* JSGC_HIGH_FREQUENCY_TIME_LIMIT */
-    static const auto HighFrequencyThreshold = mozilla::TimeDuration::FromSeconds(1);
+    static const auto HighFrequencyThreshold = 1; // in seconds
 
     /* JSGC_HIGH_FREQUENCY_LOW_LIMIT */
     static const uint64_t HighFrequencyLowLimitBytes = 100 * 1024 * 1024;
@@ -346,8 +346,6 @@ namespace TuningDefaults {
 
 }}} // namespace js::gc::TuningDefaults
 
-static const auto ONE_SECOND = mozilla::TimeDuration::FromSeconds(1);
-
 /*
  * We start to incremental collection for a zone when a proportion of its
  * threshold is reached. This is configured by the
@@ -1572,7 +1570,7 @@ GCSchedulingTunables::GCSchedulingTunables()
     allocThresholdFactorAvoidInterrupt_(TuningDefaults::AllocThresholdFactorAvoidInterrupt),
     zoneAllocDelayBytes_(TuningDefaults::ZoneAllocDelayBytes),
     dynamicHeapGrowthEnabled_(TuningDefaults::DynamicHeapGrowthEnabled),
-    highFrequencyThreshold_(TuningDefaults::HighFrequencyThreshold),
+    highFrequencyThreshold_(mozilla::TimeDuration::FromSeconds(TuningDefaults::HighFrequencyThreshold)),
     highFrequencyLowLimitBytes_(TuningDefaults::HighFrequencyLowLimitBytes),
     highFrequencyHighLimitBytes_(TuningDefaults::HighFrequencyHighLimitBytes),
     highFrequencyHeapGrowthMax_(TuningDefaults::HighFrequencyHeapGrowthMax),
@@ -1624,7 +1622,7 @@ GCSchedulingTunables::resetParameter(JSGCParamKey key, const AutoLockGC& lock)
         break;
       case JSGC_HIGH_FREQUENCY_TIME_LIMIT:
         highFrequencyThreshold_ =
-            TuningDefaults::HighFrequencyThreshold;
+            mozilla::TimeDuration::FromSeconds(TuningDefaults::HighFrequencyThreshold);
         break;
       case JSGC_HIGH_FREQUENCY_LOW_LIMIT:
         setHighFrequencyLowLimit(TuningDefaults::HighFrequencyLowLimitBytes);
@@ -2125,6 +2123,8 @@ GCRuntime::shouldCompact()
     // if we are currently animating, unless the user is inactive or we're
     // responding to memory pressure.
 
+    static const auto oneSecond = mozilla::TimeDuration::FromSeconds(1);
+
     if (invocationKind != GC_SHRINK || !isCompactingGCEnabled())
         return false;
 
@@ -2135,7 +2135,9 @@ GCRuntime::shouldCompact()
     }
 
     const auto &lastAnimationTime = rt->lastAnimationTime.ref();
-    return !isIncremental || lastAnimationTime.IsNull() || lastAnimationTime + ONE_SECOND < mozilla::TimeStamp::Now();
+    return !isIncremental
+        || lastAnimationTime.IsNull()
+        || lastAnimationTime + oneSecond < mozilla::TimeStamp::Now();
 }
 
 bool
@@ -3229,8 +3231,6 @@ ArenaLists::queueForegroundThingsForSweep()
     gcScriptArenasToUpdate = arenaListsToSweep(AllocKind::SCRIPT);
 }
 
-const mozilla::TimeStamp SliceBudget::unlimitedDeadline = mozilla::TimeStamp::Now() + mozilla::TimeDuration::Forever();
-
 SliceBudget::SliceBudget()
   : timeBudget(UnlimitedTimeBudget), workBudget(UnlimitedWorkBudget)
 {
@@ -4046,6 +4046,7 @@ bool
 GCRuntime::shouldPreserveJITCode(Realm* realm, const mozilla::TimeStamp &currentTime,
                                  JS::gcreason::Reason reason, bool canAllocateMoreCode)
 {
+    static const auto oneSecond = mozilla::TimeDuration::FromSeconds(1);
 
     if (cleanUpEverything)
         return false;
@@ -4058,7 +4059,7 @@ GCRuntime::shouldPreserveJITCode(Realm* realm, const mozilla::TimeStamp &current
         return true;
 
     const auto &lastAnimationTime = realm->lastAnimationTime.ref();
-    if (!lastAnimationTime.IsNull() && lastAnimationTime + ONE_SECOND >= currentTime)
+    if (!lastAnimationTime.IsNull() && lastAnimationTime + oneSecond >= currentTime)
         return true;
 
     if (reason == JS::gcreason::DEBUG_GC)