On Fri, May 27, 2022 at 10:36:55AM +0300, Dan Carpenter wrote: > static void match_pointer(struct expression *ret_value) > { > struct symbol *type; > char *name; > > type = cur_func_return_type(); > if (!type || sval_type_max(type).value != 1) > return; > > if (!is_pointer(ret_value)) > return; > > name = expr_to_str(ret_value); > sm_msg("'%s' return pointer cast to bool", name); > free_string(name); > } I found a bug in Smatch with this check. With the Smatch bug fixed then there is only only place which does a legitimate implied pointer to bool cast. A different function returns NULL on error instead of false. drivers/gpu/drm/i915/display/intel_dmc.c:249 intel_dmc_has_payload() 'i915->dmc.dmc_info[0]->payload' return pointer cast to bool drivers/net/wireless/rndis_wlan.c:1980 rndis_bss_info_update() '(0)' return pointer cast to bool drivers/net/wireless/rndis_wlan.c:1989 rndis_bss_info_update() '(0)' return pointer cast to bool drivers/net/wireless/rndis_wlan.c:1995 rndis_bss_info_update() '(0)' return pointer cast to bool regards, dan carpenter