On Mon, Nov 15, 2021 at 12:33:16PM +0530, Prathamesh Kulkarni wrote: > On Sun, 14 Nov 2021 at 02:07, David Malcolm via Gcc-patches
> > +/* Handle "returns_zero_on_failure" and "returns_zero_on_success" > > attributes; > > + arguments as in struct attribute_spec.handler. */ > > + > > +static tree > > +handle_returns_zero_on_attributes (tree *node, tree name, tree, int, > > + bool *no_add_attrs) > > +{ > > + if (!INTEGRAL_TYPE_P (TREE_TYPE (*node))) > > + { > > + error ("%qE attribute on a function not returning an integral type", > > + name); > > + *no_add_attrs = true; > > + } > > + return NULL_TREE; > Hi David, > Just curious if a warning should be emitted if the function is marked > with the attribute but it's return value isn't actually 0 ? > > There are other constants like -1 or 1 that are often used to indicate > error, so maybe tweak the attribute to > take the integer as an argument ? > Sth like returns_int_on_success(cst) / returns_int_on_failure(cst) ? > > Also, would it make sense to extend it for pointers too for returning > NULL on success / failure ? Please also consider that in Linux we use the 'last' page for error code returns. That is, a function returning a pointer could return '(void *)-EFAULT' also see linux/err.h