<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<!DOCTYPE bugzilla SYSTEM "https://bugs.webkit.org/page.cgi?id=bugzilla.dtd">

<bugzilla version="5.0.4.1"
          urlbase="https://bugs.webkit.org/"
          
          maintainer="admin@webkit.org"
>

    <bug>
          <bug_id>259394</bug_id>
          
          <creation_ts>2023-07-21 07:25:50 -0700</creation_ts>
          <short_desc>ASSERTION FAILED: decontaminate()</short_desc>
          <delta_ts>2025-05-23 17:38:40 -0700</delta_ts>
          <reporter_accessible>1</reporter_accessible>
          <cclist_accessible>1</cclist_accessible>
          <classification_id>1</classification_id>
          <classification>Unclassified</classification>
          <product>WebKit</product>
          <component>JavaScriptCore</component>
          <version>WebKit Nightly Build</version>
          <rep_platform>Unspecified</rep_platform>
          <op_sys>Unspecified</op_sys>
          <bug_status>RESOLVED</bug_status>
          <resolution>WORKSFORME</resolution>
          
          <see_also>https://bugs.webkit.org/show_bug.cgi?id=256189</see_also>
          <bug_file_loc></bug_file_loc>
          <status_whiteboard></status_whiteboard>
          <keywords>InRadar</keywords>
          <priority>P2</priority>
          <bug_severity>Normal</bug_severity>
          <target_milestone>---</target_milestone>
          
          
          <everconfirmed>1</everconfirmed>
          <reporter>anbu1024.me</reporter>
          <assigned_to name="Nobody">webkit-unassigned</assigned_to>
          <cc>mark.lam</cc>
    
    <cc>webkit-bug-importer</cc>
    
    <cc>ysuzuki</cc>
          

      

      

      

          <comment_sort_order>oldest_to_newest</comment_sort_order>  
          <long_desc isprivate="0" >
    <commentid>1967621</commentid>
    <comment_count>0</comment_count>
    <who name="">anbu1024.me</who>
    <bug_when>2023-07-21 07:25:50 -0700</bug_when>
    <thetext>JavaScriptCore version:

commit 77585442bf6a0acc7af584f838acd4653918b7e9

Test case:
```js
function foo() {
	const a = /\SK/ui;
	
	const b = a.exec(a);
	
	for (const c in b) {

		const d = a.iterator;		
		a[c] = d;
		
		const e = new Float64Array(59856);
		let f = 0;
		
		do {
		    const g = delete e[59856];
		    const h = e.buffer;
		    const i = f++;
		} while (f &lt; 1);
	}

	const x = b &gt;&gt; a;
	const y = parseInt();
	const z = parseInt(y);
	return z;
}

for(let i=0; i&lt;0x500; i++){
	foo();
}
```

Error msg:
```
ASSERTION FAILED: decontaminate()
WebKit/Source/JavaScriptCore/runtime/StructureID.h(131) : Structure *JSC::StructureID::decode() const
Aborted (core dumped)
```

backtrace
```
#3  JSC::StructureID::decode() const ()
#4  JSC::JSCell::structure() const ()
#5  JSC::slowValidateCell(JSC::JSCell*) ()
#6  void JSC::validateCell&lt;JSC::JSCell*&gt;(JSC::JSCell*) ()
#7  JSC::WriteBarrierBase&lt;JSC::PropertyTable, WTF::RawPtrTraits&lt;JSC::PropertyTable&gt; &gt;::get() const ()
#8  JSC::Structure::ensurePropertyTableIfNotEmpty(JSC::VM&amp;) ()
#9  JSC::Structure::get(JSC::VM&amp;, JSC::PropertyName, unsigned int&amp;) ()
#10 JSC::JSObject::getOwnNonIndexPropertySlot(JSC::VM&amp;, JSC::Structure*, JSC::PropertyName, JSC::PropertySlot&amp;) ()
#11 JSC::JSObject::getOwnPropertySlotImpl(JSC::JSObject*, JSC::JSGlobalObject*, JSC::PropertyName, JSC::PropertySlot&amp;) ()
#12 JSC::JSObject::getOwnPropertySlot(JSC::JSObject*, JSC::JSGlobalObject*, JSC::PropertyName, JSC::PropertySlot&amp;) ()
#13 JSC::RegExpObject::getOwnPropertySlot(JSC::JSObject*, JSC::JSGlobalObject*, JSC::PropertyName, JSC::PropertySlot&amp;) ()
#14 JSC::JSObject::getNonIndexPropertySlot(JSC::JSGlobalObject*, JSC::PropertyName, JSC::PropertySlot&amp;) ()
#15 bool JSC::JSObject::getPropertySlot&lt;false&gt;(JSC::JSGlobalObject*, JSC::PropertyName, JSC::PropertySlot&amp;) ()
#16 JSC::JSObject::get(JSC::JSGlobalObject*, JSC::PropertyName) const ()
#17 JSC::regExpProtoFuncToString(JSC::JSGlobalObject*, JSC::CallFrame*) ()
#18 vmEntryToNative ()
#19 JSC::Interpreter::executeCallImpl(JSC::VM&amp;, JSC::JSObject*, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;) ()
#20 JSC::Interpreter::executeCall(JSC::JSObject*, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;) ()
#21 JSC::call(JSC::JSGlobalObject*, JSC::JSValue, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;) ()
#22 JSC::JSValue JSC::callToPrimitiveFunction&lt;(JSC::CachedSpecialPropertyKey)1&gt;(JSC::JSGlobalObject*, JSC::JSObject const*, JSC::PropertyName, JSC::PreferredPrimitiveType) ()
#23 JSC::JSObject::ordinaryToPrimitive(JSC::JSGlobalObject*, JSC::PreferredPrimitiveType) const ()
#24 JSC::JSObject::toPrimitive(JSC::JSGlobalObject*, JSC::PreferredPrimitiveType) const ()
#25 JSC::JSCell::toPrimitive(JSC::JSGlobalObject*, JSC::PreferredPrimitiveType) const ()
#26 JSC::JSValue::toPrimitive(JSC::JSGlobalObject*, JSC::PreferredPrimitiveType) const ()
#27 JSC::JSValue::toBigIntOrInt32(JSC::JSGlobalObject*) const ()
#28 JSC::JSValue JSC::shift&lt;false&gt;(JSC::JSGlobalObject*, JSC::JSValue, JSC::JSValue) ()
#29 JSC::jsRShift(JSC::JSGlobalObject*, JSC::JSValue, JSC::JSValue) ()
#30 operationValueBitRShift ()
```</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1967622</commentid>
    <comment_count>1</comment_count>
    <who name="">anbu1024.me</who>
    <bug_when>2023-07-21 07:29:00 -0700</bug_when>
    <thetext>The exec cmd:
```
./jsc --validateOptions=true --thresholdForJITSoon=10 --thresholdForJITAfterWarmUp=10 --thresholdForOptimizeAfterWarmUp=40 --thresholdForOptimizeAfterLongWarmUp=40 --thresholdForOptimizeSoon=40 --thresholdForFTLOptimizeAfterWarmUp=80 --thresholdForFTLOptimizeSoon=80 --validateBCE=true hello.js
```</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1967699</commentid>
    <comment_count>2</comment_count>
    <who name="Radar WebKit Bug Importer">webkit-bug-importer</who>
    <bug_when>2023-07-21 18:09:24 -0700</bug_when>
    <thetext>&lt;rdar://problem/112690958&gt;</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1967924</commentid>
    <comment_count>3</comment_count>
    <who name="Yusuke Suzuki">ysuzuki</who>
    <bug_when>2023-07-24 15:57:51 -0700</bug_when>
    <thetext>Thanks! I tried this, however I cannot reproduce it.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>2119463</commentid>
    <comment_count>4</comment_count>
    <who name="Yusuke Suzuki">ysuzuki</who>
    <bug_when>2025-05-23 17:38:40 -0700</bug_when>
    <thetext>It doesn&apos;t reproduce.</thetext>
  </long_desc>
      
      

    </bug>

</bugzilla>