Bug 101247

Summary: Mesa fails to link GLSL programs with unused output blocks
Product: Mesa Reporter: Józef Kucia <joseph.kucia>
Component: glsl-compilerAssignee: mesa-dev
Status: RESOLVED FIXED QA Contact: Intel 3D Bugs Mailing List <intel-3d-bugs>
Severity: normal    
Priority: medium    
Version: git   
Hardware: All   
OS: All   
See Also: https://bugs.winehq.org/show_bug.cgi?id=43057
i915 platform: i915 features:

Description Józef Kucia 2017-05-31 11:42:16 UTC
Mesa fails to link GLSL programs with unused output blocks declared in a shader object other than the main one.

piglit: https://lists.freedesktop.org/archives/piglit/2017-May/022302.html

This bugs affects multiple application in Wine when GL core profiles are enabled.
Comment 1 Samuel Pitoiset 2017-05-31 13:02:16 UTC
Thanks for reporting this. I saw your piglit test yesterday. It's a bug yes.
Comment 2 vadym 2018-08-22 11:19:09 UTC
Patch: https://patchwork.freedesktop.org/patch/245518/
Comment 3 vadym 2018-08-27 10:37:00 UTC
Patch merged to master:

commit 4a8444d5bc865119218eca8674e5614535f4829e (HEAD -> new_master, origin/master, origin/HEAD)
Author: vadym.shovkoplias <vadim.shovkoplias@gmail.com>
Date:   Thu Aug 23 13:12:16 2018 +0300

    glsl/linker: Allow unused in blocks which are not declated on previous stage
    >From Section 4.3.4 (Inputs) of the GLSL 1.50 spec:
        "Only the input variables that are actually read need to be written
         by the previous stage; it is allowed to have superfluous
         declarations of input variables."
        * interstage-multiple-shader-objects.shader_test
      Update comment in ir.h since the usage of "used" field
      has been extended.
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101247
    Signed-off-by: Vadym Shovkoplias <vadym.shovkoplias@globallogic.com>
    Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
    Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>

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