On Tuesday 2021-10-05 22:37, Steven Rostedt wrote: > >Really, thinking about abstraction, I don't believe there's anything wrong >with returning a pointer of one type, and then typecasting it to a pointer >of another type. Is there? As long as whoever uses the returned type does >nothing with it. Illegal. https://en.cppreference.com/w/c/language/conversion subsection "Pointer conversion" "No other guarantees are offered" >struct trace_pid_list *trace_pid_list_alloc(void) >{ > struct pid_list *pid_list; > > pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); > [..] > > return (struct trace_pid_list *)pid_list; >} struct trace_pid_list { void *pid_list; }; struct trace_pid_list trace_pid_list_alloc(void) { struct trace_pid_list t; t.pid_list = kmalloc(sizeof(t.orig), GFP_KERNEL); return t; } void freethat(struct strace_pid_list x) { kfree(x.pid_list); } Might run afoul of -Waggregate-return in C.
