Bug 177215 - [JSC] JSTests/stress/ftl-put-by-id-slow-exception-no-catch.js is failing due to incorrect IC
Summary: [JSC] JSTests/stress/ftl-put-by-id-slow-exception-no-catch.js is failing due ...
Status: RESOLVED INVALID
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-09-19 18:41 PDT by Caio Lima
Modified: 2017-09-22 11:57 PDT (History)
6 users (show)

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Description Caio Lima 2017-09-19 18:41:26 PDT 
The problem is happening when an Inline Cache is created using a Structure that is collected by GC and a further Structure with a different shape is allocated at the same address. In that case, the IC code is invalid, but the Structure comparison will succeed and then the wrong offset is being used.

Steps to reproduce:

```run-jsc --count 500 JSTests/stress/ftl-put-by-id-slow-exception-no-catch.js```
Comment 1 Caio Lima 2017-09-22 11:57:47 PDT 
False alarm. The reason is a downstream Patch.