[Mesa-dev] [PATCH] glsl: do not reset prog->TransformFeedback.BufferStride

[Juan A. Suarez Romero]

On Wed, 2017-06-21 at 20:24 +1000, Timothy Arceri wrote:
> On 21/06/17 18:13, Juan A. Suarez Romero wrote:
> > link_xfb_stride_layout_qualifiers() can be called multiple times, and
> > each time we call prog->TransformFeedback.BufferStride is reset to 0.
> > 
> > Thus it is loosing the values set in previous call.
> > 
> > Do not perform such reset.
> > 
> > Fixes:
> > KHR-GL45.enhanced_layouts.xfb_stride_of_empty_list
> > KHR-GL45.enhanced_layouts.xfb_stride_of_empty_list_and_api
> > 
> > Signed-off-by: Juan A. Suarez Romero <jasuarez at igalia.com>
> > ---
> >   src/compiler/glsl/linker.cpp | 4 ----
> >   1 file changed, 4 deletions(-)
> > 
> > diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp
> > index adfa3b7b1d..1fe0ccc496 100644
> > --- a/src/compiler/glsl/linker.cpp
> > +++ b/src/compiler/glsl/linker.cpp
> > @@ -1623,10 +1623,6 @@ link_xfb_stride_layout_qualifiers(struct gl_context *ctx,
> >                                     struct gl_shader **shader_list,
> >                                     unsigned num_shaders)
> >   {
> > -   for (unsigned i = 0; i < MAX_FEEDBACK_BUFFERS; i++) {
> > -      prog->TransformFeedback.BufferStride[i] = 0;
> > -   }
> 
> I think this probably needs to be moved rather than just deleted. I 
> think the idea is to reset things to 0 in case we are re-linking an 
> existing program with different shaders attached.
> 

Checking how this was done prior the refactoring in 4d65f68 (mesa/glsl:
move TransformFeedbackBufferStride to gl_shader), actually the reset
should be done if the new shaders provide an explicit xfb_stride.
Otherwise we should kept the old value.

I'm sending a new version.


> > -
> >      for (unsigned i = 0; i < num_shaders; i++) {
> >         struct gl_shader *shader = shader_list[i];
> >   
> > 
> 
>