mesa: unmap the immediate mode VB before destroying it

Fixes failed assertion from fd.o bug 27713.

The assertion was added with the new resource/transfer changes.
This patch could apply to the 7.8 branch but it's not essential.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/mesa/vbo/vbo_exec_api.c b/src/mesa/vbo/vbo_exec_api.c
index e83bd9e404..0ccbb42383 100644
--- a/src/mesa/vbo/vbo_exec_api.c
+++ b/src/mesa/vbo/vbo_exec_api.c
@@ -850,8 +850,11 @@ void vbo_exec_vtx_destroy( struct vbo_exec_context *exec )
                                     NULL);
    }
 
-   /* Free the vertex buffer:
+   /* Free the vertex buffer.  Unmap first if needed.
     */
+   if (_mesa_bufferobj_mapped(exec->vtx.bufferobj)) {
+      ctx->Driver.UnmapBuffer(ctx, GL_ARRAY_BUFFER, exec->vtx.bufferobj);
+   }
    _mesa_reference_buffer_object(ctx, &exec->vtx.bufferobj, NULL);
 }