Remove remaining conditional GCZeal code.

Creates stubs:
jsgc.h/cpp
VerifyBarriers() stub
MaybeVerifyBarriers() stub
GCRuntime::computeNonIncrementalMarkingForValidation() stub
GCRuntime::validateIncrementalMarking() stub
GCRuntime::finishMarkingValidation() stub
GCRuntime::pushZealSelectedObjects() stub
bool useZeal?
GCRuntime::runDebugGC() stub
XPConnect:
nsXPCComponents_Utils::SetGCZeal() stub (always NS_OK)

19 files changed, 4 insertions, 814 deletions

diff --git a/js/src/jit/CompileWrappers.h b/js/src/jit/CompileWrappers.h
index bbec9ffa34..ccded4f13b 100644
--- a/js/src/jit/CompileWrappers.h
+++ b/js/src/jit/CompileWrappers.h
@@ -51,10 +51,6 @@ class CompileRuntime
     // &runtime()->activation_
     const void* addressOfActivation();
 
-#ifdef JS_GC_ZEAL
-    const void* addressOfGCZealModeBits();
-#endif
-
     const void* addressOfInterruptUint32();
 
     // We have to bake JSContext* into JIT code, but this pointer shouldn't be
diff --git a/js/src/jit/VMFunctions.cpp b/js/src/jit/VMFunctions.cpp
index 628b31fae4..a299d27a5d 100644
--- a/js/src/jit/VMFunctions.cpp
+++ b/js/src/jit/VMFunctions.cpp
@@ -627,11 +627,7 @@ PostWriteElementBarrier(JSRuntime* rt, JSObject* obj, int32_t index)
     if (obj->is<NativeObject>() &&
         !obj->as<NativeObject>().isInWholeCellBuffer() &&
         uint32_t(index) < obj->as<NativeObject>().getDenseInitializedLength() &&
-        (obj->as<NativeObject>().getDenseInitializedLength() > MAX_WHOLE_CELL_BUFFER_SIZE
-#ifdef JS_GC_ZEAL
-         || rt->hasZealMode(gc::ZealMode::ElementsBarrier)
-#endif
-        ))
+        (obj->as<NativeObject>().getDenseInitializedLength() > MAX_WHOLE_CELL_BUFFER_SIZE))
     {
         rt->gc.storeBuffer.putSlot(&obj->as<NativeObject>(), HeapSlot::Element, index, 1);
         return;
diff --git a/js/src/js-config.h.in b/js/src/js-config.h.in
index f2ce93e122..779446fd75 100644
--- a/js/src/js-config.h.in
+++ b/js/src/js-config.h.in
@@ -38,10 +38,6 @@
 /* Define to 1 if SpiderMonkey should include ctypes support.  */
 #undef JS_HAS_CTYPES
 
-/* Define to 1 if SpiderMonkey should support the ability to perform
-   entirely too much GC.  */
-#undef JS_GC_ZEAL
-
 /* Define to 1 if SpiderMonkey should use small chunks. */
 #undef JS_GC_SMALL_CHUNK_SIZE
 
diff --git a/js/src/jsapi-tests/testGCFinalizeCallback.cpp b/js/src/jsapi-tests/testGCFinalizeCallback.cpp
index 48003ab0ce..a8f7ba7f88 100644
--- a/js/src/jsapi-tests/testGCFinalizeCallback.cpp
+++ b/js/src/jsapi-tests/testGCFinalizeCallback.cpp
@@ -94,36 +94,6 @@ BEGIN_TEST(testGCFinalizeCallback)
     CHECK(checkFinalizeStatus());
     CHECK(checkFinalizeIsZoneGC(true));
 
-#ifdef JS_GC_ZEAL
-
-    /* Full GC with reset due to new zone, becoming zone GC. */
-
-    FinalizeCalls = 0;
-    JS_SetGCZeal(cx, 9, 1000000);
-    JS::PrepareForFullGC(cx);
-    js::SliceBudget budget(js::WorkBudget(1));
-    cx->gc.startDebugGC(GC_NORMAL, budget);
-    CHECK(cx->gc.state() == js::gc::State::Mark);
-    CHECK(cx->gc.isFullGc());
-
-    JS::RootedObject global4(cx, createTestGlobal());
-    budget = js::SliceBudget(js::WorkBudget(1));
-    cx->gc.debugGCSlice(budget);
-    while (cx->gc.isIncrementalGCInProgress())
-        cx->gc.debugGCSlice(budget);
-    CHECK(!cx->gc.isIncrementalGCInProgress());
-    CHECK(!cx->gc.isFullGc());
-    CHECK(checkMultipleGroups());
-    CHECK(checkFinalizeStatus());
-
-    for (unsigned i = 0; i < FinalizeCalls - 1; ++i)
-        CHECK(!IsZoneGCBuffer[i]);
-    CHECK(IsZoneGCBuffer[FinalizeCalls - 1]);
-
-    JS_SetGCZeal(cx, 0, 0);
-
-#endif
-
     /*
      * Make some use of the globals here to ensure the compiler doesn't optimize
      * them away in release builds, causing the zones to be collected and
diff --git a/js/src/jsapi-tests/testGCHeapPostBarriers.cpp b/js/src/jsapi-tests/testGCHeapPostBarriers.cpp
index 74512a53fa..00d47f1118 100644
--- a/js/src/jsapi-tests/testGCHeapPostBarriers.cpp
+++ b/js/src/jsapi-tests/testGCHeapPostBarriers.cpp
@@ -40,10 +40,6 @@ JSFunction* CreateGCThing(JSContext* cx)
 
 BEGIN_TEST(testGCHeapPostBarriers)
 {
-#ifdef JS_GC_ZEAL
-    AutoLeaveZeal nozeal(cx);
-#endif /* JS_GC_ZEAL */
-
     /* Sanity check - objects start in the nursery and then become tenured. */
     JS_GC(cx);
     JS::RootedObject obj(cx, CreateGCThing<JSObject>(cx));
diff --git a/js/src/jsapi-tests/testGCMarking.cpp b/js/src/jsapi-tests/testGCMarking.cpp
index 6843973921..b475c2d696 100644
--- a/js/src/jsapi-tests/testGCMarking.cpp
+++ b/js/src/jsapi-tests/testGCMarking.cpp
@@ -101,10 +101,6 @@ class CCWTestTracer : public JS::CallbackTracer {
 
 BEGIN_TEST(testTracingIncomingCCWs)
 {
-#ifdef JS_GC_ZEAL
-    // Disable zeal modes because this test needs to control exactly when the GC happens.
-    JS_SetGCZeal(cx, 0, 100);
-#endif
     JS_GC(cx);
 
     JS::RootedObject global1(cx, JS::CurrentGlobalOrNull(cx));
@@ -146,10 +142,6 @@ countWrappers(JSCompartment* comp)
 
 BEGIN_TEST(testDeadNurseryCCW)
 {
-#ifdef JS_GC_ZEAL
-    // Disable zeal modes because this test needs to control exactly when the GC happens.
-    JS_SetGCZeal(cx, 0, 100);
-#endif
     JS_GC(cx);
 
     JS::RootedObject global1(cx, JS::CurrentGlobalOrNull(cx));
@@ -177,10 +169,6 @@ END_TEST(testDeadNurseryCCW)
 
 BEGIN_TEST(testLiveNurseryCCW)
 {
-#ifdef JS_GC_ZEAL
-    // Disable zeal modes because this test needs to control exactly when the GC happens.
-    JS_SetGCZeal(cx, 0, 100);
-#endif
     JS_GC(cx);
 
     JS::RootedObject global1(cx, JS::CurrentGlobalOrNull(cx));
@@ -208,10 +196,6 @@ END_TEST(testLiveNurseryCCW)
 
 BEGIN_TEST(testLiveNurseryWrapperCCW)
 {
-#ifdef JS_GC_ZEAL
-    // Disable zeal modes because this test needs to control exactly when the GC happens.
-    JS_SetGCZeal(cx, 0, 100);
-#endif
     JS_GC(cx);
 
     JS::RootedObject global1(cx, JS::CurrentGlobalOrNull(cx));
@@ -244,10 +228,6 @@ END_TEST(testLiveNurseryWrapperCCW)
 
 BEGIN_TEST(testLiveNurseryWrappeeCCW)
 {
-#ifdef JS_GC_ZEAL
-    // Disable zeal modes because this test needs to control exactly when the GC happens.
-    JS_SetGCZeal(cx, 0, 100);
-#endif
     JS_GC(cx);
 
     JS::RootedObject global1(cx, JS::CurrentGlobalOrNull(cx));
@@ -280,11 +260,6 @@ BEGIN_TEST(testIncrementalRoots)
 {
     JSRuntime* rt = cx->runtime();
 
-#ifdef JS_GC_ZEAL
-    // Disable zeal modes because this test needs to control exactly when the GC happens.
-    JS_SetGCZeal(cx, 0, 100);
-#endif
-
     // Construct a big object graph to mark. In JS, the resulting object graph
     // is equivalent to:
     //
diff --git a/js/src/jsapi-tests/testGCUniqueId.cpp b/js/src/jsapi-tests/testGCUniqueId.cpp
index 71d66b7221..d03d51b045 100644
--- a/js/src/jsapi-tests/testGCUniqueId.cpp
+++ b/js/src/jsapi-tests/testGCUniqueId.cpp
@@ -23,10 +23,6 @@ MinimizeHeap(JSContext* cx)
 
 BEGIN_TEST(testGCUID)
 {
-#ifdef JS_GC_ZEAL
-    AutoLeaveZeal nozeal(cx);
-#endif /* JS_GC_ZEAL */
-
     uint64_t uid = 0;
     uint64_t tmp = 0;
 
diff --git a/js/src/jsapi-tests/tests.h b/js/src/jsapi-tests/tests.h
index 9955621ef1..7f7309c161 100644
--- a/js/src/jsapi-tests/tests.h
+++ b/js/src/jsapi-tests/tests.h
@@ -418,39 +418,4 @@ class TestJSPrincipals : public JSPrincipals
     }
 };
 
-#ifdef JS_GC_ZEAL
-/*
- * Temporarily disable the GC zeal setting. This is only useful in tests that
- * need very explicit GC behavior and should not be used elsewhere.
- */
-class AutoLeaveZeal
-{
-    JSContext* cx_;
-    uint32_t zealBits_;
-    uint32_t frequency_;
-
-  public:
-    explicit AutoLeaveZeal(JSContext* cx) : cx_(cx) {
-        uint32_t dummy;
-        JS_GetGCZealBits(cx_, &zealBits_, &frequency_, &dummy);
-        JS_SetGCZeal(cx_, 0, 0);
-        JS::PrepareForFullGC(cx_);
-        JS::GCForReason(cx_, GC_SHRINK, JS::gcreason::DEBUG_GC);
-    }
-    ~AutoLeaveZeal() {
-        for (size_t i = 0; i < sizeof(zealBits_) * 8; i++) {
-            if (zealBits_ & (1 << i))
-                JS_SetGCZeal(cx_, i, frequency_);
-        }
-
-#ifdef DEBUG
-        uint32_t zealBitsAfter, frequencyAfter, dummy;
-        JS_GetGCZealBits(cx_, &zealBitsAfter, &frequencyAfter, &dummy);
-        MOZ_ASSERT(zealBitsAfter == zealBits_);
-        MOZ_ASSERT(frequencyAfter == frequency_);
-#endif
-    }
-};
-#endif /* JS_GC_ZEAL */
-
 #endif /* jsapi_tests_tests_h */
diff --git a/js/src/jsapi.cpp b/js/src/jsapi.cpp
index e4e86effac..ee9c610594 100644
--- a/js/src/jsapi.cpp
+++ b/js/src/jsapi.cpp
@@ -6263,26 +6263,6 @@ JS_AbortIfWrongThread(JSContext* cx)
         MOZ_CRASH();
 }
 
-#ifdef JS_GC_ZEAL
-JS_PUBLIC_API(void)
-JS_GetGCZealBits(JSContext* cx, uint32_t* zealBits, uint32_t* frequency, uint32_t* nextScheduled)
-{
-    cx->runtime()->gc.getZealBits(zealBits, frequency, nextScheduled);
-}
-
-JS_PUBLIC_API(void)
-JS_SetGCZeal(JSContext* cx, uint8_t zeal, uint32_t frequency)
-{
-    cx->gc.setZeal(zeal, frequency);
-}
-
-JS_PUBLIC_API(void)
-JS_ScheduleGC(JSContext* cx, uint32_t count)
-{
-    cx->runtime()->gc.setNextScheduled(count);
-}
-#endif
-
 JS_PUBLIC_API(void)
 JS_SetParallelParsingEnabled(JSContext* cx, bool enabled)
 {
diff --git a/js/src/jsgc.cpp b/js/src/jsgc.cpp
index 42d10283c4..4fa51417fc 100644
--- a/js/src/jsgc.cpp
+++ b/js/src/jsgc.cpp
@@ -844,9 +844,6 @@ GCRuntime::GCRuntime(JSRuntime* rt) :
     arenasAllocatedDuringSweep(nullptr),
     startedCompacting(false),
     relocatedArenasToRelease(nullptr),
-#ifdef JS_GC_ZEAL
-    markingValidator(nullptr),
-#endif
     interFrameGC(false),
     defaultTimeBudget_(SliceBudget::UnlimitedTimeBudget),
     incrementalAllowed(true),
@@ -856,13 +853,6 @@ GCRuntime::GCRuntime(JSRuntime* rt) :
     manipulatingDeadZones(false),
     objectsMarkedInDeadZones(0),
     poked(false),
-#ifdef JS_GC_ZEAL
-    zealModeBits(0),
-    zealFrequency(0),
-    nextScheduled(0),
-    deterministicOnly(false),
-    incrementalLimit(0),
-#endif
     fullCompartmentChecks(false),
     mallocBytesUntilGC(0),
     mallocGCTriggered(false),
@@ -881,147 +871,6 @@ GCRuntime::GCRuntime(JSRuntime* rt) :
     setGCMode(JSGC_MODE_GLOBAL);
 }
 
-#ifdef JS_GC_ZEAL
-
-void
-GCRuntime::getZealBits(uint32_t* zealBits, uint32_t* frequency, uint32_t* scheduled)
-{
-    *zealBits = zealModeBits;
-    *frequency = zealFrequency;
-    *scheduled = nextScheduled;
-}
-
-const char* gc::ZealModeHelpText =
-    "  Specifies how zealous the garbage collector should be. Some of these modes can\n"
-    "  be set simultaneously, by passing multiple level options, e.g. \"2;4\" will activate\n"
-    "  both modes 2 and 4. Modes can be specified by name or number.\n"
-    "  \n"
-    "  Values:\n"
-    "    0: (None) Normal amount of collection (resets all modes)\n"
-    "    1: (Poke) Collect when roots are added or removed\n"
-    "    2: (Alloc) Collect when every N allocations (default: 100)\n"
-    "    3: (FrameGC) Collect when the window paints (browser only)\n"
-    "    4: (VerifierPre) Verify pre write barriers between instructions\n"
-    "    5: (FrameVerifierPre) Verify pre write barriers between paints\n"
-    "    6: (StackRooting) Verify stack rooting\n"
-    "    7: (GenerationalGC) Collect the nursery every N nursery allocations\n"
-    "    8: (IncrementalRootsThenFinish) Incremental GC in two slices: 1) mark roots 2) finish collection\n"
-    "    9: (IncrementalMarkAllThenFinish) Incremental GC in two slices: 1) mark all 2) new marking and finish\n"
-    "   10: (IncrementalMultipleSlices) Incremental GC in multiple slices\n"
-    "   11: (IncrementalMarkingValidator) Verify incremental marking\n"
-    "   12: (ElementsBarrier) Always use the individual element post-write barrier, regardless of elements size\n"
-    "   13: (CheckHashTablesOnMinorGC) Check internal hashtables on minor GC\n"
-    "   14: (Compact) Perform a shrinking collection every N allocations\n"
-    "   15: (CheckHeapAfterGC) Walk the heap to check its integrity after every GC\n"
-    "   16: (CheckNursery) Check nursery integrity on minor GC\n";
-
-void
-GCRuntime::setZeal(uint8_t zeal, uint32_t frequency)
-{
-    MOZ_ASSERT(zeal <= unsigned(ZealMode::Limit));
-
-    if (verifyPreData)
-        VerifyBarriers(rt, PreBarrierVerifier);
-
-    if (zeal == 0 && hasZealMode(ZealMode::GenerationalGC)) {
-        evictNursery(JS::gcreason::DEBUG_GC);
-        nursery.leaveZealMode();
-    }
-
-    ZealMode zealMode = ZealMode(zeal);
-    if (zealMode == ZealMode::GenerationalGC)
-        nursery.enterZealMode();
-
-    // Zeal modes 8-10 are mutually exclusive. If we're setting one of those,
-    // we first reset all of them.
-    if (zealMode >= ZealMode::IncrementalRootsThenFinish &&
-        zealMode <= ZealMode::IncrementalMultipleSlices)
-    {
-        clearZealMode(ZealMode::IncrementalRootsThenFinish);
-        clearZealMode(ZealMode::IncrementalMarkAllThenFinish);
-        clearZealMode(ZealMode::IncrementalMultipleSlices);
-    }
-
-    bool schedule = zealMode >= ZealMode::Alloc;
-    if (zeal != 0)
-        zealModeBits |= 1 << unsigned(zeal);
-    else
-        zealModeBits = 0;
-    zealFrequency = frequency;
-    nextScheduled = schedule ? frequency : 0;
-}
-
-void
-GCRuntime::setNextScheduled(uint32_t count)
-{
-    nextScheduled = count;
-}
-
-bool
-GCRuntime::parseAndSetZeal(const char* str)
-{
-    int frequency = -1;
-    bool foundFrequency = false;
-    mozilla::Vector<int, 0, SystemAllocPolicy> zeals;
-
-    static const struct {
-        const char* const zealMode;
-        size_t length;
-        uint32_t zeal;
-    } zealModes[] = {
-#define ZEAL_MODE(name, value) {#name, sizeof(#name) - 1, value},
-        JS_FOR_EACH_ZEAL_MODE(ZEAL_MODE)
-#undef ZEAL_MODE
-        {"None", 4, 0}
-    };
-
-    do {
-        int zeal = -1;
-
-        const char* p = nullptr;
-        if (isdigit(str[0])) {
-            zeal = atoi(str);
-
-            size_t offset = strspn(str, "0123456789");
-            p = str + offset;
-        } else {
-            for (auto z : zealModes) {
-                if (!strncmp(str, z.zealMode, z.length)) {
-                    zeal = z.zeal;
-                    p = str + z.length;
-                    break;
-                }
-            }
-        }
-        if (p) {
-            if (!*p || *p == ';') {
-                frequency = JS_DEFAULT_ZEAL_FREQ;
-            } else if (*p == ',') {
-                frequency = atoi(p + 1);
-                foundFrequency = true;
-            }
-        }
-
-        if (zeal < 0 || zeal > int(ZealMode::Limit) || frequency <= 0) {
-            fprintf(stderr, "Format: JS_GC_ZEAL=level(;level)*[,N]\n");
-            fputs(ZealModeHelpText, stderr);
-            return false;
-        }
-
-        if (!zeals.emplaceBack(zeal)) {
-            return false;
-        }
-    } while (!foundFrequency &&
-             (str = strchr(str, ';')) != nullptr &&
-             str++);
-
-    for (auto z : zeals)
-        setZeal(z, frequency);
-    return true;
-}
-
-#endif
-
 /*
  * Lifetime in number of major GCs for type sets attached to scripts containing
  * observed types.
@@ -1063,12 +912,6 @@ GCRuntime::init(uint32_t maxbytes, uint32_t maxNurseryBytes)
         }
     }
 
-#ifdef JS_GC_ZEAL
-    const char* zealSpec = getenv("JS_GC_ZEAL");
-    if (zealSpec && zealSpec[0] && !parseAndSetZeal(zealSpec))
-        return false;
-#endif
-
     if (!InitTrace(*this))
         return false;
 
@@ -1094,11 +937,6 @@ GCRuntime::finish()
     allocTask.cancel(GCParallelTask::CancelAndWait);
     decommitTask.cancel(GCParallelTask::CancelAndWait);
 
-#ifdef JS_GC_ZEAL
-    /* Free memory associated with GC verification. */
-    finishVerifier();
-#endif
-
     /* Delete all remaining zones. */
     if (rt->gcInitialized) {
         AutoSetThreadIsSweeping threadIsSweeping;
@@ -2635,7 +2473,7 @@ GCRuntime::releaseRelocatedArenasWithoutUnlocking(Arena* arenaList, const AutoLo
         // Mark arena as empty
         arena->setAsFullyUnused();
 
-#if defined(JS_CRASH_DIAGNOSTICS) || defined(JS_GC_ZEAL)
+#if defined(JS_CRASH_DIAGNOSTICS)
         JS_POISON(reinterpret_cast<void*>(arena->thingsStart()),
                   JS_MOVED_TENURED_PATTERN, arena->getThingsSpan());
 #endif
@@ -3048,13 +2886,6 @@ GCRuntime::triggerZoneGC(Zone* zone, JS::gcreason::Reason reason)
     if (rt->isHeapCollecting())
         return false;
 
-#ifdef JS_GC_ZEAL
-    if (hasZealMode(ZealMode::Alloc)) {
-        MOZ_RELEASE_ASSERT(triggerGC(reason));
-        return true;
-    }
-#endif
-
     if (zone->isAtomsZone()) {
         /* We can't do a zone GC of the atoms compartment. */
         if (rt->keepAtoms()) {
@@ -3077,14 +2908,6 @@ GCRuntime::maybeGC(Zone* zone)
 {
     MOZ_ASSERT(CurrentThreadCanAccessRuntime(rt));
 
-#ifdef JS_GC_ZEAL
-    if (hasZealMode(ZealMode::Alloc) || hasZealMode(ZealMode::Poke)) {
-        JS::PrepareForFullGC(rt->contextFromMainThread());
-        gc(GC_NORMAL, JS::gcreason::DEBUG_GC);
-        return;
-    }
-#endif
-
     if (gcIfRequested())
         return;
 
@@ -3418,11 +3241,6 @@ GCRuntime::shouldReleaseObservedTypes()
 {
     bool releaseTypes = false;
 
-#ifdef JS_GC_ZEAL
-    if (zealModeBits != 0)
-        releaseTypes = true;
-#endif
-
     /* We may miss the exact target GC due to resets. */
     if (majorGCNumber >= jitReleaseNumber)
         releaseTypes = true;
@@ -4068,290 +3886,19 @@ GCRuntime::markAllGrayReferences(gcstats::Phase phase)
     markGrayReferences<GCZonesIter, GCCompartmentsIter>(phase);
 }
 
-#ifdef JS_GC_ZEAL
-
-struct GCChunkHasher {
-    typedef gc::Chunk* Lookup;
-
-    /*
-     * Strip zeros for better distribution after multiplying by the golden
-     * ratio.
-     */
-    static HashNumber hash(gc::Chunk* chunk) {
-        MOZ_ASSERT(!(uintptr_t(chunk) & gc::ChunkMask));
-        return HashNumber(uintptr_t(chunk) >> gc::ChunkShift);
-    }
-
-    static bool match(gc::Chunk* k, gc::Chunk* l) {
-        MOZ_ASSERT(!(uintptr_t(k) & gc::ChunkMask));
-        MOZ_ASSERT(!(uintptr_t(l) & gc::ChunkMask));
-        return k == l;
-    }
-};
-
-class js::gc::MarkingValidator
-{
-  public:
-    explicit MarkingValidator(GCRuntime* gc);
-    ~MarkingValidator();
-    void nonIncrementalMark(AutoLockForExclusiveAccess& lock);
-    void validate();
-
-  private:
-    GCRuntime* gc;
-    bool initialized;
-
-    typedef HashMap<Chunk*, ChunkBitmap*, GCChunkHasher, SystemAllocPolicy> BitmapMap;
-    BitmapMap map;
-};
-
-js::gc::MarkingValidator::MarkingValidator(GCRuntime* gc)
-  : gc(gc),
-    initialized(false)
-{}
-
-js::gc::MarkingValidator::~MarkingValidator()
-{
-    if (!map.initialized())
-        return;
-
-    for (BitmapMap::Range r(map.all()); !r.empty(); r.popFront())
-        js_delete(r.front().value());
-}
-
-void
-js::gc::MarkingValidator::nonIncrementalMark(AutoLockForExclusiveAccess& lock)
-{
-    /*
-     * Perform a non-incremental mark for all collecting zones and record
-     * the results for later comparison.
-     *
-     * Currently this does not validate gray marking.
-     */
-
-    if (!map.init())
-        return;
-
-    JSRuntime* runtime = gc->rt;
-    GCMarker* gcmarker = &gc->marker;
-
-    gc->waitBackgroundSweepEnd();
-
-    /* Save existing mark bits. */
-    for (auto chunk = gc->allNonEmptyChunks(); !chunk.done(); chunk.next()) {
-        ChunkBitmap* bitmap = &chunk->bitmap;
-	ChunkBitmap* entry = js_new<ChunkBitmap>();
-        if (!entry)
-            return;
-
-        memcpy((void*)entry->bitmap, (void*)bitmap->bitmap, sizeof(bitmap->bitmap));
-        if (!map.putNew(chunk, entry))
-            return;
-    }
-
-    /*
-     * Temporarily clear the weakmaps' mark flags for the compartments we are
-     * collecting.
-     */
-
-    WeakMapSet markedWeakMaps;
-    if (!markedWeakMaps.init())
-        return;
-
-    /*
-     * For saving, smush all of the keys into one big table and split them back
-     * up into per-zone tables when restoring.
-     */
-    gc::WeakKeyTable savedWeakKeys(SystemAllocPolicy(), runtime->randomHashCodeScrambler());
-    if (!savedWeakKeys.init())
-        return;
-
-    for (GCZonesIter zone(runtime); !zone.done(); zone.next()) {
-        if (!WeakMapBase::saveZoneMarkedWeakMaps(zone, markedWeakMaps))
-            return;
-
-        AutoEnterOOMUnsafeRegion oomUnsafe;
-        for (gc::WeakKeyTable::Range r = zone->gcWeakKeys.all(); !r.empty(); r.popFront()) {
-            if (!savedWeakKeys.put(Move(r.front().key), Move(r.front().value)))
-                oomUnsafe.crash("saving weak keys table for validator");
-        }
-
-        if (!zone->gcWeakKeys.clear())
-            oomUnsafe.crash("clearing weak keys table for validator");
-    }
-
-    /*
-     * After this point, the function should run to completion, so we shouldn't
-     * do anything fallible.
-     */
-    initialized = true;
-
-    /* Re-do all the marking, but non-incrementally. */
-    js::gc::State state = gc->incrementalState;
-    gc->incrementalState = State::MarkRoots;
-
-    {
-        gcstats::AutoPhase ap(gc->stats, gcstats::PHASE_MARK);
-
-        {
-            gcstats::AutoPhase ap(gc->stats, gcstats::PHASE_UNMARK);
-
-            for (GCZonesIter zone(runtime); !zone.done(); zone.next())
-                WeakMapBase::unmarkZone(zone);
-
-            MOZ_ASSERT(gcmarker->isDrained());
-            gcmarker->reset();
-
-            for (auto chunk = gc->allNonEmptyChunks(); !chunk.done(); chunk.next())
-                chunk->bitmap.clear();
-        }
-
-        gc->traceRuntimeForMajorGC(gcmarker, lock);
-
-        gc->incrementalState = State::Mark;
-        auto unlimited = SliceBudget::unlimited();
-        MOZ_RELEASE_ASSERT(gc->marker.drainMarkStack(unlimited));
-    }
-
-    gc->incrementalState = State::Sweep;
-    {
-        gcstats::AutoPhase ap1(gc->stats, gcstats::PHASE_SWEEP);
-        gcstats::AutoPhase ap2(gc->stats, gcstats::PHASE_SWEEP_MARK);
-
-        gc->markAllWeakReferences(gcstats::PHASE_SWEEP_MARK_WEAK);
-
-        /* Update zone state for gray marking. */
-        for (GCZonesIter zone(runtime); !zone.done(); zone.next()) {
-            MOZ_ASSERT(zone->isGCMarkingBlack());
-            zone->setGCState(Zone::MarkGray);
-        }
-        gc->marker.setMarkColorGray();
-
-        gc->markAllGrayReferences(gcstats::PHASE_SWEEP_MARK_GRAY);
-        gc->markAllWeakReferences(gcstats::PHASE_SWEEP_MARK_GRAY_WEAK);
-
-        /* Restore zone state. */
-        for (GCZonesIter zone(runtime); !zone.done(); zone.next()) {
-            MOZ_ASSERT(zone->isGCMarkingGray());
-            zone->setGCState(Zone::Mark);
-        }
-        MOZ_ASSERT(gc->marker.isDrained());
-        gc->marker.setMarkColorBlack();
-    }
-
-    /* Take a copy of the non-incremental mark state and restore the original. */
-    for (auto chunk = gc->allNonEmptyChunks(); !chunk.done(); chunk.next()) {
-        ChunkBitmap* bitmap = &chunk->bitmap;
-        ChunkBitmap* entry = map.lookup(chunk)->value();
-        Swap(*entry, *bitmap);
-    }
-
-    for (GCZonesIter zone(runtime); !zone.done(); zone.next()) {
-        WeakMapBase::unmarkZone(zone);
-        AutoEnterOOMUnsafeRegion oomUnsafe;
-        if (!zone->gcWeakKeys.clear())
-            oomUnsafe.crash("clearing weak keys table for validator");
-    }
-
-    WeakMapBase::restoreMarkedWeakMaps(markedWeakMaps);
-
-    for (gc::WeakKeyTable::Range r = savedWeakKeys.all(); !r.empty(); r.popFront()) {
-        AutoEnterOOMUnsafeRegion oomUnsafe;
-        Zone* zone = gc::TenuredCell::fromPointer(r.front().key.asCell())->zone();
-        if (!zone->gcWeakKeys.put(Move(r.front().key), Move(r.front().value)))
-            oomUnsafe.crash("restoring weak keys table for validator");
-    }
-
-    gc->incrementalState = state;
-}
-
-void
-js::gc::MarkingValidator::validate()
-{
-    /*
-     * Validates the incremental marking for a single compartment by comparing
-     * the mark bits to those previously recorded for a non-incremental mark.
-     */
-
-    if (!initialized)
-        return;
-
-    gc->waitBackgroundSweepEnd();
-
-    for (auto chunk = gc->allNonEmptyChunks(); !chunk.done(); chunk.next()) {
-        BitmapMap::Ptr ptr = map.lookup(chunk);
-        if (!ptr)
-            continue;  /* Allocated after we did the non-incremental mark. */
-
-        ChunkBitmap* bitmap = ptr->value();
-        ChunkBitmap* incBitmap = &chunk->bitmap;
-
-        for (size_t i = 0; i < ArenasPerChunk; i++) {
-            if (chunk->decommittedArenas.get(i))
-                continue;
-            Arena* arena = &chunk->arenas[i];
-            if (!arena->allocated())
-                continue;
-            if (!arena->zone->isGCSweeping())
-                continue;
-            if (arena->allocatedDuringIncremental)
-                continue;
-
-            AllocKind kind = arena->getAllocKind();
-            uintptr_t thing = arena->thingsStart();
-            uintptr_t end = arena->thingsEnd();
-            while (thing < end) {
-                Cell* cell = (Cell*)thing;
-
-                /*
-                 * If a non-incremental GC wouldn't have collected a cell, then
-                 * an incremental GC won't collect it.
-                 */
-                MOZ_ASSERT_IF(bitmap->isMarked(cell, BLACK), incBitmap->isMarked(cell, BLACK));
-
-                /*
-                 * If the cycle collector isn't allowed to collect an object
-                 * after a non-incremental GC has run, then it isn't allowed to
-                 * collected it after an incremental GC.
-                 */
-                MOZ_ASSERT_IF(!bitmap->isMarked(cell, GRAY), !incBitmap->isMarked(cell, GRAY));
-
-                thing += Arena::thingSize(kind);
-            }
-        }
-    }
-}
-
-#endif // JS_GC_ZEAL
-
 void
 GCRuntime::computeNonIncrementalMarkingForValidation(AutoLockForExclusiveAccess& lock)
 {
-#ifdef JS_GC_ZEAL
-    MOZ_ASSERT(!markingValidator);
-    if (isIncremental && hasZealMode(ZealMode::IncrementalMarkingValidator))
-        markingValidator = js_new<MarkingValidator>(this);
-    if (markingValidator)
-        markingValidator->nonIncrementalMark(lock);
-#endif
 }
 
 void
 GCRuntime::validateIncrementalMarking()
 {
-#ifdef JS_GC_ZEAL
-    if (markingValidator)
-        markingValidator->validate();
-#endif
 }
 
 void
 GCRuntime::finishMarkingValidation()
 {
-#ifdef JS_GC_ZEAL
-    js_delete(markingValidator);
-    markingValidator = nullptr;
-#endif
 }
 
 static void
@@ -5785,11 +5332,6 @@ AutoGCSlice::~AutoGCSlice()
 void
 GCRuntime::pushZealSelectedObjects()
 {
-#ifdef JS_GC_ZEAL
-    /* Push selected objects onto the mark stack and clear the list. */
-    for (JSObject** obj = selectedForMarking.begin(); obj != selectedForMarking.end(); obj++)
-        TraceManuallyBarrieredEdge(&marker, obj, "selected obj");
-#endif
 }
 
 static bool
@@ -5818,16 +5360,6 @@ GCRuntime::incrementalCollectSlice(SliceBudget& budget, JS::gcreason::Reason rea
     gc::State initialState = incrementalState;
 
     bool useZeal = false;
-#ifdef JS_GC_ZEAL
-    if (reason == JS::gcreason::DEBUG_GC && !budget.isUnlimited()) {
-        /*
-         * Do the incremental collection type specified by zeal mode if the
-         * collection was triggered by runDebugGC() and incremental GC has not
-         * been cancelled by resetIncrementalGC().
-         */
-        useZeal = true;
-    }
-#endif
 
     MOZ_ASSERT_IF(isIncrementalGCInProgress(), isIncremental);
     isIncremental = !budget.isUnlimited();
@@ -6202,11 +5734,6 @@ GCRuntime::gcCycle(bool nonincrementalByAPI, SliceBudget& budget, JS::gcreason::
 
     chunkAllocationSinceLastGC = false;
 
-#ifdef JS_GC_ZEAL
-    /* Keeping these around after a GC is dangerous. */
-    clearSelectedForMarking();
-#endif
-
     /* Clear gcMallocBytes for all zones. */
     for (ZonesIter zone(rt, WithAtoms); !zone.done(); zone.next())
         zone->resetGCMallocBytes();
@@ -6218,23 +5745,6 @@ GCRuntime::gcCycle(bool nonincrementalByAPI, SliceBudget& budget, JS::gcreason::
     return false;
 }
 
-#ifdef JS_GC_ZEAL
-static bool
-IsDeterministicGCReason(JS::gcreason::Reason reason)
-{
-    if (reason > JS::gcreason::DEBUG_GC &&
-        reason != JS::gcreason::CC_FORCED && reason != JS::gcreason::SHUTDOWN_CC)
-    {
-        return false;
-    }
-
-    if (reason == JS::gcreason::EAGER_ALLOC_TRIGGER)
-        return false;
-
-    return true;
-}
-#endif
-
 gcstats::ZoneGCStats
 GCRuntime::scanZonesBeforeGC()
 {
@@ -6300,11 +5810,6 @@ GCRuntime::checkIfGCAllowedInCurrentState(JS::gcreason::Reason reason)
     if (rt->isBeingDestroyed() && !IsShutdownGC(reason))
         return false;
 
-#ifdef JS_GC_ZEAL
-    if (deterministicOnly && !IsDeterministicGCReason(reason))
-        return false;
-#endif
-
     return true;
 }
 
@@ -6360,13 +5865,6 @@ GCRuntime::collect(bool nonincrementalByAPI, SliceBudget budget, JS::gcreason::R
 
     if (reason == JS::gcreason::COMPARTMENT_REVIVED)
         maybeDoCycleCollection();
-
-#ifdef JS_GC_ZEAL
-    if (rt->hasZealMode(ZealMode::CheckHeapAfterGC)) {
-        gcstats::AutoPhase ap(rt->gc.stats, gcstats::PHASE_TRACE_HEAP);
-        CheckHeapAfterGC(rt);
-    }
-#endif
 }
 
 js::AutoEnqueuePendingParseTasksAfterGC::~AutoEnqueuePendingParseTasksAfterGC()
@@ -6460,17 +5958,6 @@ GCRuntime::notifyDidPaint()
 {
     MOZ_ASSERT(CurrentThreadCanAccessRuntime(rt));
 
-#ifdef JS_GC_ZEAL
-    if (hasZealMode(ZealMode::FrameVerifierPre))
-        verifyPreBarriers();
-
-    if (hasZealMode(ZealMode::FrameGC)) {
-        JS::PrepareForFullGC(rt->contextFromMainThread());
-        gc(GC_NORMAL, JS::gcreason::REFRESH_FRAME);
-        return;
-    }
-#endif
-
     if (isIncrementalGCInProgress() && !interFrameGC && tunables.areRefreshFrameSlicesEnabled()) {
         JS::PrepareForIncrementalGC(rt->contextFromMainThread());
         gcSlice(JS::gcreason::REFRESH_FRAME);
@@ -6566,11 +6053,6 @@ GCRuntime::minorGC(JS::gcreason::Reason reason, gcstats::Phase phase)
 
     blocksToFreeAfterMinorGC.freeAll();
 
-#ifdef JS_GC_ZEAL
-    if (rt->hasZealMode(ZealMode::CheckHeapAfterGC))
-        CheckHeapAfterGC(rt);
-#endif
-
     {
         AutoLockGC lock(rt);
         for (ZonesIter zone(rt, WithAtoms); !zone.done(); zone.next())
@@ -6756,59 +6238,6 @@ gc::MergeCompartments(JSCompartment* source, JSCompartment* target)
 void
 GCRuntime::runDebugGC()
 {
-#ifdef JS_GC_ZEAL
-    if (rt->mainThread.suppressGC)
-        return;
-
-    if (hasZealMode(ZealMode::GenerationalGC))
-        return minorGC(JS::gcreason::DEBUG_GC);
-
-    PrepareForDebugGC(rt);
-
-    auto budget = SliceBudget::unlimited();
-    if (hasZealMode(ZealMode::IncrementalRootsThenFinish) ||
-        hasZealMode(ZealMode::IncrementalMarkAllThenFinish) ||
-        hasZealMode(ZealMode::IncrementalMultipleSlices))
-    {
-        js::gc::State initialState = incrementalState;
-        if (hasZealMode(ZealMode::IncrementalMultipleSlices)) {
-            /*
-             * Start with a small slice limit and double it every slice. This
-             * ensure that we get multiple slices, and collection runs to
-             * completion.
-             */
-            if (!isIncrementalGCInProgress())
-                incrementalLimit = zealFrequency / 2;
-            else
-                incrementalLimit *= 2;
-            budget = SliceBudget(WorkBudget(incrementalLimit));
-        } else {
-            // This triggers incremental GC but is actually ignored by IncrementalMarkSlice.
-            budget = SliceBudget(WorkBudget(1));
-        }
-
-        if (!isIncrementalGCInProgress())
-            invocationKind = GC_SHRINK;
-        collect(false, budget, JS::gcreason::DEBUG_GC);
-
-        /*
-         * For multi-slice zeal, reset the slice size when we get to the sweep
-         * or compact phases.
-         */
-        if (hasZealMode(ZealMode::IncrementalMultipleSlices)) {
-            if ((initialState == State::Mark && incrementalState == State::Sweep) ||
-                (initialState == State::Sweep && incrementalState == State::Compact))
-            {
-                incrementalLimit = zealFrequency / 2;
-            }
-        }
-    } else if (hasZealMode(ZealMode::Compact)) {
-        gc(GC_SHRINK, JS::gcreason::DEBUG_GC);
-    } else {
-        gc(GC_NORMAL, JS::gcreason::DEBUG_GC);
-    }
-
-#endif
 }
 
 void
@@ -6818,28 +6247,6 @@ GCRuntime::setFullCompartmentChecks(bool enabled)
     fullCompartmentChecks = enabled;
 }
 
-#ifdef JS_GC_ZEAL
-bool
-GCRuntime::selectForMarking(JSObject* object)
-{
-    MOZ_ASSERT(!rt->isHeapMajorCollecting());
-    return selectedForMarking.append(object);
-}
-
-void
-GCRuntime::clearSelectedForMarking()
-{
-    selectedForMarking.clearAndFree();
-}
-
-void
-GCRuntime::setDeterministic(bool enabled)
-{
-    MOZ_ASSERT(!rt->isHeapMajorCollecting());
-    deterministicOnly = enabled;
-}
-#endif
-
 #ifdef DEBUG
 
 /* Should only be called manually under gdb */
diff --git a/js/src/jsgc.h b/js/src/jsgc.h
index 79ac9596c5..c0d86781d5 100644
--- a/js/src/jsgc.h
+++ b/js/src/jsgc.h
@@ -1264,19 +1264,6 @@ enum VerifierType {
     PreBarrierVerifier
 };
 
-#ifdef JS_GC_ZEAL
-
-extern const char* ZealModeHelpText;
-
-/* Check that write barriers have been used correctly. See jsgc.cpp. */
-void
-VerifyBarriers(JSRuntime* rt, VerifierType type);
-
-void
-MaybeVerifyBarriers(JSContext* cx, bool always = false);
-
-#else
-
 static inline void
 VerifyBarriers(JSRuntime* rt, VerifierType type)
 {
@@ -1287,8 +1274,6 @@ MaybeVerifyBarriers(JSContext* cx, bool always = false)
 {
 }
 
-#endif
-
 /*
  * Instances of this class set the |JSRuntime::suppressGC| flag for the duration
  * that they are live. Use of this class is highly discouraged. Please carefully
diff --git a/js/src/jspubtd.h b/js/src/jspubtd.h
index 309b9d7466..20ea1ef8b1 100644
--- a/js/src/jspubtd.h
+++ b/js/src/jspubtd.h
@@ -22,7 +22,7 @@
 #include "js/TraceKind.h"
 #include "js/TypeDecls.h"
 
-#if defined(JS_GC_ZEAL) || defined(DEBUG)
+#if defined(DEBUG)
 # define JSGC_HASH_TABLE_CHECKS
 #endif
 
diff --git a/js/src/jsutil.h b/js/src/jsutil.h
index 790b97ddca..8ef4cac908 100644
--- a/js/src/jsutil.h
+++ b/js/src/jsutil.h
@@ -368,7 +368,7 @@ Poison(void* ptr, uint8_t value, size_t num)
 #endif
 
 /* Enable poisoning in crash-diagnostics and zeal builds. */
-#if defined(JS_CRASH_DIAGNOSTICS) || defined(JS_GC_ZEAL)
+#if defined(JS_CRASH_DIAGNOSTICS)
 # define JS_POISON(p, val, size) Poison(p, val, size)
 #else
 # define JS_POISON(p, val, size) ((void) 0)
diff --git a/js/src/old-configure.in b/js/src/old-configure.in
index 1c5c9e2145..e4589b951b 100644
--- a/js/src/old-configure.in
+++ b/js/src/old-configure.in
@@ -1806,17 +1806,6 @@ if test -n "$MOZ_DEBUG"; then
 fi
 
 dnl ========================================================
-dnl Zealous JavaScript GC
-dnl ========================================================
-MOZ_ARG_ENABLE_BOOL(gczeal,
-[  --enable-gczeal         Enable zealous GCing],
-    JS_GC_ZEAL=1,
-    JS_GC_ZEAL= )
-if test -n "$JS_GC_ZEAL" -o -n "$MOZ_DEBUG"; then
-    AC_DEFINE(JS_GC_ZEAL)
-fi
-
-dnl ========================================================
 dnl Enable breakpoint for artificial OOMs
 dnl ========================================================
 MOZ_ARG_ENABLE_BOOL(oom-breakpoint,
diff --git a/js/src/shell/js.cpp b/js/src/shell/js.cpp
index 00a4a503ce..88d482a238 100644
--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -323,10 +323,6 @@ static bool enableNativeRegExp = false;
 static bool enableUnboxedArrays = false;
 static bool enableSharedMemory = SHARED_MEMORY_DEFAULT;
 static bool enableWasmAlwaysBaseline = false;
-#ifdef JS_GC_ZEAL
-static uint32_t gZealBits = 0;
-static uint32_t gZealFrequency = 0;
-#endif
 static bool printTiming = false;
 static const char* jsCacheDir = nullptr;
 static const char* jsCacheAsmJSPath = nullptr;
@@ -7517,16 +7513,6 @@ SetContextOptions(JSContext* cx, const OptionParser& op)
     dumpEntrainedVariables = op.getBoolOption("dump-entrained-variables");
 #endif
 
-#ifdef JS_GC_ZEAL
-    const char* zealStr = op.getStringOption("gc-zeal");
-    if (zealStr) {
-        if (!cx->gc.parseAndSetZeal(zealStr))
-            return false;
-        uint32_t nextScheduled;
-        cx->gc.getZealBits(&gZealBits, &gZealFrequency, &nextScheduled);
-    }
-#endif
-
     return true;
 }
 
@@ -7544,16 +7530,6 @@ SetWorkerContextOptions(JSContext* cx)
     cx->setOffthreadIonCompilationEnabled(offthreadCompilation);
     cx->profilingScripts = enableCodeCoverage || enableDisassemblyDumps;
 
-#ifdef JS_GC_ZEAL
-    if (gZealBits && gZealFrequency) {
-#define ZEAL_MODE(_, value)                        \
-        if (gZealBits & (1 << value))              \
-            cx->gc.setZeal(value, gZealFrequency);
-        JS_FOR_EACH_ZEAL_MODE(ZEAL_MODE)
-#undef ZEAL_MODE
-    }
-#endif
-
     JS_SetNativeStackQuota(cx, gMaxStackSize);
 }
 
@@ -7838,9 +7814,6 @@ main(int argc, char** argv, char** envp)
                             "NUMBER of instructions.", -1)
 #endif
         || !op.addIntOption('\0', "nursery-size", "SIZE-MB", "Set the maximum nursery size in MB", 16)
-#ifdef JS_GC_ZEAL
-        || !op.addStringOption('z', "gc-zeal", "LEVEL(;LEVEL)*[,N]", gc::ZealModeHelpText)
-#endif
         || !op.addStringOption('\0', "module-load-path", "DIR", "Set directory to load modules from")
     )
     {
diff --git a/js/src/vm/EnvironmentObject.h b/js/src/vm/EnvironmentObject.h
index 6bdaac89e8..d457ca8392 100644
--- a/js/src/vm/EnvironmentObject.h
+++ b/js/src/vm/EnvironmentObject.h
@@ -930,9 +930,6 @@ class DebugEnvironments
     void mark(JSTracer* trc);
     void sweep(JSRuntime* rt);
     void finish();
-#ifdef JS_GC_ZEAL
-    void checkHashTablesAfterMovingGC(JSRuntime* rt);
-#endif
 
     // If a live frame has a synthesized entry in missingEnvs, make sure it's not
     // collected.
diff --git a/js/xpconnect/src/XPCComponents.cpp b/js/xpconnect/src/XPCComponents.cpp
index ca78234c9a..02b0b4d148 100644
--- a/js/xpconnect/src/XPCComponents.cpp
+++ b/js/xpconnect/src/XPCComponents.cpp
@@ -3007,9 +3007,6 @@ GENERATE_JSCONTEXTOPTION_GETTER_SETTER(Ion, ion, setIon)
 NS_IMETHODIMP
 nsXPCComponents_Utils::SetGCZeal(int32_t aValue, JSContext* cx)
 {
-#ifdef JS_GC_ZEAL
-    JS_SetGCZeal(cx, uint8_t(aValue), JS_DEFAULT_ZEAL_FREQ);
-#endif
     return NS_OK;
 }
 
diff --git a/js/xpconnect/src/XPCJSContext.cpp b/js/xpconnect/src/XPCJSContext.cpp
index 6981b525c5..defd1b7852 100644
--- a/js/xpconnect/src/XPCJSContext.cpp
+++ b/js/xpconnect/src/XPCJSContext.cpp
@@ -1473,16 +1473,6 @@ ReloadPrefsCallback(const char* pref, void* data)
     sExtraWarningsForSystemJS = Preferences::GetBool(JS_OPTIONS_DOT_STR "strict.debug");
 #endif
 
-#ifdef JS_GC_ZEAL
-    int32_t zeal = Preferences::GetInt(JS_OPTIONS_DOT_STR "gczeal", -1);
-    int32_t zeal_frequency =
-        Preferences::GetInt(JS_OPTIONS_DOT_STR "gczeal.frequency",
-                            JS_DEFAULT_ZEAL_FREQ);
-    if (zeal >= 0) {
-        JS_SetGCZeal(cx, (uint8_t)zeal, zeal_frequency);
-    }
-#endif // JS_GC_ZEAL
-
     JS::ContextOptionsRef(cx).setBaseline(useBaseline)
                              .setIon(useIon)
                              .setAsmJS(useAsmJS)
diff --git a/js/xpconnect/src/XPCShellImpl.cpp b/js/xpconnect/src/XPCShellImpl.cpp
index d86b5c5d3e..d9629bfeda 100644
--- a/js/xpconnect/src/XPCShellImpl.cpp
+++ b/js/xpconnect/src/XPCShellImpl.cpp
@@ -440,21 +440,6 @@ GC(JSContext* cx, unsigned argc, Value* vp)
     return true;
 }
 
-#ifdef JS_GC_ZEAL
-static bool
-GCZeal(JSContext* cx, unsigned argc, Value* vp)
-{
-    CallArgs args = CallArgsFromVp(argc, vp);
-    uint32_t zeal;
-    if (!ToUint32(cx, args.get(0), &zeal))
-        return false;
-
-    JS_SetGCZeal(cx, uint8_t(zeal), JS_DEFAULT_ZEAL_FREQ);
-    args.rval().setUndefined();
-    return true;
-}
-#endif
-
 static bool
 SendCommand(JSContext* cx, unsigned argc, Value* vp)
 {
@@ -652,9 +637,6 @@ static const JSFunctionSpec glob_functions[] = {
     JS_FS("dumpXPC",         DumpXPC,        1,0),
     JS_FS("dump",            Dump,           1,0),
     JS_FS("gc",              GC,             0,0),
-#ifdef JS_GC_ZEAL
-    JS_FS("gczeal",          GCZeal,         1,0),
-#endif
     JS_FS("options",         Options,        0,0),
     JS_FS("sendCommand",     SendCommand,    1,0),
     JS_FS("atob",            xpc::Atob,      1,0),