----- Original Message ----- > On Mon, 23 Apr 2012 10:30:41 -0700 (PDT), Benoit Jacob > <bja...@mozilla.com> wrote: > > > > > > ----- Original Message ----- > > > On Sat, 21 Apr 2012 08:09:33 -0700 (PDT), Benoit Jacob > > > <bja...@mozilla.com> wrote: > > > > > > conformance/programs/program-test.html: 1 tests failed > > > > > > > > > > > PASS linking should fail with in-use formerly good program, > > > > > > with > > > > > > new bad shader attached > > > > > > FAIL getError expected: NO_ERROR. Was INVALID_OPERATION : > > > > > > drawing > > > > > > with a > > > > > > valid program shouldn't generate a GL error > > > > > > > > > > This sounded like it was going to be a Mesa bug, but this > > > > > testcase > > > > > passes: > > > > > > > > This is indeed Mesa's bug: on failure, glLinkProgram should > > > > leave a > > > > previously-successfully-linked program intact. The testcase in > > > > your email doesn't seem to be re-linking the program with the > > > > bad > > > > shader, which would explain why it doesn't reproduce this > > > > issue. > > > > > > It should? I read the opposite in this quote from the GL 3.0 > > > spec: > > > > > > "Linking will also fail if one or more of the shader objects, > > > attached to program are not compiled successfully, or if > > > more > > > active uniform or active sampler variables are used in > > > program > > > than > > > allowed (see section 2.20.3). If LinkProgram failed, any > > > information about a previous link of that program object is > > > lost. Thus, a failed link does not restore the old state of > > > program." > > > > Thanks, I hadn't questioned that the test might be wrong, but now I > > agree with you. Also, the same phrasing is found in the OpenGL ES > > 2.0.25 spec page 30: > > > > "If LinkProgram failed, any information about a previous link of > > that program object is lost. Thus, a failed link does not restore > > the old state of program." > > > > Reporting this to the WebGL mailing list. > > I did find this gem later: > > "If that program object that is in use is re-linked > unsuccessfully, > the link status will be set to FALSE, but existing executable > and > associated state will remain part of the current rendering state > until a subsequent call to UseProgram removes it from use." > > Maybe they're testing that. I wonder what possible use was imagined > for > forcing that sort of complexity on driver developers.
Yes, the public_webgl list got a reply quoting that sentence as the reason for the unit test's behavior. I must say I sympathize with you on this, but since it's what the spec says and what a majority of GL implementations do, let's keep it that way. Cheers, Benoit > _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
