draw: don't crash if GS doesn't emit anything

Technically it's legal for geometry shader to not emit any
vertices. It's silly, but perfectly legal, so lets make draw
stop crashing if it happens.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: José Fonseca <jfonseca@vmware.com>
Reviewed-by: Roland Scheidegger <sroland@vmware.com>

diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
index 7b871c2952d792244ef80a492f763daf4721ef12..8d66c885436ea3bf27fa4ed82692f806c88592d8 100644 (file)
--- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
+++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
@@ -299,6 +299,15 @@ static void fetch_pipeline_generic( struct draw_pt_middle_end *middle,
          }
       }
    }
+   if (prim_info->count == 0) {
+      debug_printf("GS/IA didn't emit any vertices!\n");
+      
+      FREE(vert_info->verts);
+      if (free_prim_info) {
+         FREE(prim_info->primitive_lengths);
+      }
+      return;
+   }
 
 
    /* Stream output needs to be done before clipping.

diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
index 0873e342a2d4db11af0f2d176f4da1ac373fcae8..48fb6165bdcd039055095f80caff08b8924212e4 100644 (file)
--- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
+++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
@@ -397,6 +397,15 @@ llvm_pipeline_generic( struct draw_pt_middle_end *middle,
          }
       }
    }
+   if (prim_info->count == 0) {
+      debug_printf("GS/IA didn't emit any vertices!\n");
+      
+      FREE(vert_info->verts);
+      if (free_prim_info) {
+         FREE(prim_info->primitive_lengths);
+      }
+      return;
+   }
 
    /* stream output needs to be done before clipping */
    draw_pt_so_emit( fpme->so_emit, vert_info, prim_info );