777883 - Avoid calling glLinkProgram when we know that a bad shader is attached

Status: RESOLVED FIXED

(Core :: Graphics: CanvasWebGL, defect)

Description

[Benoit Jacob [:bjacob] (mostly away)]

This is preventing program-test.html from passing on Mac OSX 10.8 with AMD cards. Incidentally it also is what caused us to run into ANGLE bug 351 whem we tried to update ANGLE to r1226 (bug 774755).

The issue is that when a program is currently in-use, attaching bad shaders to it and relinking it should leave its state untouched. This is tested by program-test.html. Many drivers including AMD/MacOSX10.8 fail that and ANGLE r1226 crashed on that (fixed in ANGLE 1242).

The workaround is to check if bad shaders are attached before actually calling glLinkProgram. So, more validation on our side, more shadowing of GL state such as shaders' "compile status" etc.

Note that WebGLShader already had something called its "translation success" but that is a different thing, it's about GLSL ES -> native shader translation.

Comment 1

[Benoit Jacob [:bjacob] (mostly away)]

Attachment: glLinkProgram work-around

Note, doing the work-around unconditionally because it is needed on a wide variety of drivers. I think i've seen this bug in Mesa, etc.

Comment 2

[Kelsey Gilbert [:jgilbert]]

Comment on attachment 646286 [details] [diff] [review]
glLinkProgram work-around

Review of attachment 646286 [details] [diff] [review]:
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Gross that we have to do this, but oh well.

Comment 3

[Benoit Jacob [:bjacob] (mostly away)]

http://hg.mozilla.org/integration/mozilla-inbound/rev/d641b8b46aa0

Comment 4

[(no longer active)]

https://hg.mozilla.org/mozilla-central/rev/d641b8b46aa0