- if (!ctx->Extensions.ARB_draw_buffers) {
- _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffersARB");
- return;
- }
- if (n < 1 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
+ /* Turns out n==0 is a valid input that should not produce an error.
+ * The remaining code below correctly handles the n==0 case.
+ */
+ if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {