Bug 47914 – Hang when passing array into shader compile

• Status: RESOLVED
• Resolution: FIXED
• Component: WebGL

[Dean Jackson]

See the attached file. Notice that I forgot to make the fragment source into a string (I left off the .join("\n")). I get a hang when trying to compile an array, rather than an error.

[Dean Jackson]

Created attachment 71188 [details]
test case (WILL HANG if WebGL is enabled)

[Simon Fraser (smfr)]

<rdar://problem/8568702>

[Zhenyao Mo]

Am I the only one that can't view the test case?

[Dean Jackson]

There isn't anything to view in the test case. It simply hangs on OSX Safari.

I have not tried in Chrome or other platforms. I don't know if the hang is in webcore or the driver.

[Zhenyao Mo]

(In reply to comment #4)
> There isn't anything to view in the test case. It simply hangs on OSX Safari.
> 
> I have not tried in Chrome or other platforms. I don't know if the hang is in webcore or the driver.

I mean it's an empty test case.  I couldn't download or see the content.

[Dean Jackson]

Are you saying that when you view source there is nothing there? There is definitely 1.17kb of something :)

It sounds to me like Chrome (which I assume you're using) doesn't hang, because in Safari you'd immediately get a beach ball and be forced to kill -9.

But yes, there is actually no output. I will update this.

[Zhenyao Mo]

OK, I just figured out how to view the source of the test.  I could reproduce the hang in Chromium too.

I'll have a look at the issue.

[Zhenyao Mo]

The hang is in ANGLE.  I'll dig further to the exact cause.  cc Alok on this.

[Zhenyao Mo]

OK, here is the issue, JS/V8 will automatically map string arrays to a string, only that ','s are inserted in between.

Somehow the below text cause Angle to halt:

#ifdef GL_ES,precision mediump float;,#endif,,void main(),{,    gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);,}

[Zhenyao Mo]

Filed a bug in Angle.

http://code.google.com/p/angleproject/issues/detail?id=67

[Zhenyao Mo]

It's been fixed in ANGLE r506