Bug 233720 – Add static_assert the value we use to initialize a StructureID buffer should be 0.

• Status: RESOLVED
• Resolution: FIXED
• Component: New Bugs

[Keith Miller]

Fix GCC warning about memcpy into a StructureID* buffer

[Keith Miller]

Created attachment 445606 [details]
Patch

[Yusuke Suzuki]

Comment on attachment 445606 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=445606&action=review

> Source/JavaScriptCore/runtime/StructureChain.cpp:52
> +    static_assert(!StructureID().bits(), "Make sure the value we're going to memcpy below matches the default StructureID");

This part looks good.

> Source/JavaScriptCore/runtime/StructureID.h:55
> +    constexpr uint32_t bits() const { return m_bits; }

Nice.

[Keith Miller]

Created attachment 445607 [details]
Patch for landing

[Michael Catanzaro]

Comment on attachment 445607 [details]
Patch for landing

View in context: https://bugs.webkit.org/attachment.cgi?id=445607&action=review

> Source/JavaScriptCore/runtime/StructureChain.cpp:53
>      memset(vector, 0, bytes);

I'm skeptical that would be enough to suppress this warning. We'll probably need to do:

memset(static_cast<void*>(vector), 0, bytes);

If your patch alone isn't enough, I'll just commit this as a follow-up.

[Keith Miller]

(In reply to Michael Catanzaro from comment #4)
> Comment on attachment 445607 [details]
> Patch for landing
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=445607&action=review
> 
> > Source/JavaScriptCore/runtime/StructureChain.cpp:53
> >      memset(vector, 0, bytes);
> 
> I'm skeptical that would be enough to suppress this warning. We'll probably
> need to do:
> 
> memset(static_cast<void*>(vector), 0, bytes);
> 
> If your patch alone isn't enough, I'll just commit this as a follow-up.

Oh, this is just the static_assert now since Yusuke already landed a cast change.

[Michael Catanzaro]

Ack, see: bug #233379 for the warning fix.

[EWS]

Committed r286387 (244744@main): <https://commits.webkit.org/244744@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 445607 [details].

[Radar WebKit Bug Importer]

<rdar://problem/85939821>