Bug 67926

[softpipe] piglit tesselation polygon wireframe regression

mesa: 2c2e64edaba0f6aeb181ca5b51eb8dea8e9b39f9 (master)


$ ./bin/ext_transform_feedback-tessellation polygon wireframe -auto
Segmentation fault (core dumped)

(gdb) bt
#0  0x00007fb5df2ba92e in sp_setup_line (setup=0x9ed330, v0=0xac4280, v1=0xbc21c0) at sp_setup.c:1074
#1  0x00007fb5df2a8f42 in sp_vbuf_draw_elements (vbr=0x9ed290, indices=0x9effd0, nr=6) at sp_prim_vbuf.c:180
#2  0x00007fb5df18f6c8 in vbuf_flush_vertices (vbuf=0x9eff10) at draw/draw_pipe_vbuf.c:327
#3  0x00007fb5df18f8ca in vbuf_flush (stage=0x9eff10, flags=4) at draw/draw_pipe_vbuf.c:392
#4  0x00007fb5df18ddde in unfilled_flush (stage=0x933860, flags=4) at draw/draw_pipe_unfilled.c:209
#5  0x00007fb5df189303 in cull_flush (stage=0x9e7210, flags=4) at draw/draw_pipe_cull.c:231
#6  0x00007fb5df188acd in clip_flush (stage=0x9e0b10, flags=4) at draw/draw_pipe_clip.c:748
#7  0x00007fb5df182226 in draw_pipeline_flush (draw=0x9dc800, flags=4) at draw/draw_pipe.c:353
#8  0x00007fb5df17b9b6 in draw_do_flush (draw=0x9dc800, flags=4) at draw/draw_context.c:722
#9  0x00007fb5df17ad9e in draw_flush (draw=0x9dc800) at draw/draw_context.c:225
#10 0x00007fb5df2a8b2a in softpipe_draw_vbo (pipe=0x945080, info=0x7ffff056a420) at sp_draw_arrays.c:145
#11 0x00007fb5df17968a in cso_draw_vbo (cso=0xa775a0, info=0x7ffff056a420) at cso_cache/cso_context.c:1413
#12 0x00007fb5df084526 in st_draw_vbo (ctx=0xa0b920, prims=0x7ffff056a4e0, nr_prims=1, ib=0x0, index_bounds_valid=1 '\001', min_index=0, max_index=4, 
    tfb_vertcount=0x0) at ../../src/mesa/state_tracker/st_draw.c:286
#13 0x00007fb5df04082d in vbo_draw_arrays (ctx=0xa0b920, mode=9, start=0, count=5, numInstances=1, baseInstance=0)
    at ../../src/mesa/vbo/vbo_exec_array.c:624
#14 0x00007fb5df04127e in vbo_exec_DrawArrays (mode=9, start=0, count=5) at ../../src/mesa/vbo/vbo_exec_array.c:776
#15 0x00007fb5e2c43d9c in stub_glDrawArrays (mode=9, first=0, count=5) at piglit/tests/util/generated_dispatch.c:6223
#16 0x00000000004021b0 in draw (prog=3, use_xfb=false, y_offset=64, mode=9, num_vertices=5)
    at piglit/tests/spec/ext_transform_feedback/tessellation.c:446
#17 0x0000000000402836 in piglit_display () at piglit/tests/spec/ext_transform_feedback/tessellation.c:618
#18 0x00007fb5e2c35e1c in display () at piglit/tests/util/piglit-framework-gl/piglit_glut_framework.c:60
#19 0x00007fb5e23d3fc4 in fghRedrawWindow (window=0x91a140) at freeglut_main.c:210
#20 fghcbDisplayWindow (window=0x91a140, enumerator=0x7ffff056a9c0) at freeglut_main.c:227
#21 0x00007fb5e23d7719 in fgEnumWindows (enumCallback=enumCallback@entry=0x7fb5e23d3f20 <fghcbDisplayWindow>, enumerator=enumerator@entry=0x7ffff056a9c0)
    at freeglut_structure.c:394
#22 0x00007fb5e23d445c in fghDisplayAll () at freeglut_main.c:249
#23 glutMainLoopEvent () at freeglut_main.c:1450
#24 0x00007fb5e23d4d81 in glutMainLoop () at freeglut_main.c:1498
#25 0x00007fb5e2c3604b in run_test (gl_fw=0x7fb5e2f1e040 <glut_fw>, argc=3, argv=0x7ffff056ad78)
    at piglit/tests/util/piglit-framework-gl/piglit_glut_framework.c:142
#26 0x00007fb5e2c340e9 in piglit_gl_test_run (argc=3, argv=0x7ffff056ad78, config=0x7ffff056ac60)
    at piglit/tests/util/piglit-framework-gl.c:141
#27 0x0000000000401a81 in main (argc=3, argv=0x7ffff056ad78) at piglit/tests/spec/ext_transform_feedback/tessellation.c:131
(gdb) frame 0
#0  0x00007fb5df2ba92e in sp_setup_line (setup=0x9ed330, v0=0xac4280, v1=0xbc21c0) at sp_setup.c:1074
1074	   int x1 = (int) v1[0][0];
(gdb) print v1[0]
Cannot access memory at address 0xbc21c0


d6b3a193d4d525c5048ebf793e6a63fd98f92d64 is the first bad commit
commit d6b3a193d4d525c5048ebf793e6a63fd98f92d64
Author: Zack Rusin <zackr@vmware.com>
Date:   Wed Jul 31 07:34:49 2013 -0400

    draw: inject frontface info into wireframe outputs
    
    Draw module can decompose primitives into wireframe models, which
    is a fancy word for 'lines', unfortunately that decomposition means
    that we weren't able to preserve the original front-face info which
    could be derived from the original primitives (lines don't have a
    'face'). To fix it allow draw module to inject a fake face semantic
    into outputs from which the backends can figure out the original
    frontfacing info of the primitives.
    
    Signed-off-by: Zack Rusin <zackr@vmware.com>
    Reviewed-by: Roland Scheidegger <sroland@vmware.com>
    Reviewed-by: Jose Fonseca <jfonseca@vmware.com>

:040000 040000 c03c3c58f6b2d41a576aa2c1388323bc4fdfb21e cb98c963ea0f7797496053122ad6b5c3f56a1861 M	src
bisect run success