on a recent submit to LKML https://lore.kernel.org/lkml/20230801170255.163237-1-jim.cromie@gmail.com/ I got a Patchwork CI warning in report: https://patchwork.freedesktop.org/series/113363/ 1a864a4fe7ce dyndbg-API: fix CONFIG_DRM_USE_DYNAMIC_DEBUG regression -:445: CHECK:MACRO_ARG_REUSE: Macro argument reuse '_var' - possible side-effects? #445: FILE: include/linux/dynamic_debug.h:120: +#define DYNDBG_CLASSMAP_USE_(_var, _uname) \ + extern struct ddebug_class_map _var; \ + struct ddebug_class_user __used \ + __section("__dyndbg_class_users") _uname = { \ + .user_mod_name = KBUILD_MODNAME, \ + .map = &_var, \ } _var is expanded 2x, the "extra" time is to declare it as "extern", meaning its exported elsewhere. the usual fix for macro problems like this is __typeof(); something like: #define foo(a,b,...) \ typeof(a) _a = a; \ ... but I dont see how to use it - I need _var to name the struct exported from another module, and I need to take its &-address. Is there a trick / technique I can use ?