mesa: no-op glBufferSubData() on size==0

Fixes http://bugs.freedesktop.org/show_bug.cgi?id=31439

NOTE: this is a candidate for the 7.9 branch

diff --git a/src/mesa/main/bufferobj.c b/src/mesa/main/bufferobj.c
index 0a68008a1003fba28671f42a0f83517b54f68d87..76f8259a283912d0e53b1f81995cb660d1d00699 100644 (file)
--- a/src/mesa/main/bufferobj.c
+++ b/src/mesa/main/bufferobj.c
@@ -1189,6 +1189,9 @@ _mesa_BufferSubDataARB(GLenum target, GLintptrARB offset,
       return;
    }
 
+   if (size == 0)
+      return;
+
    bufObj->Written = GL_TRUE;
 
    ASSERT(ctx->Driver.BufferSubData);