Closed
Description
We're inconsistent in how we format/word comments in examples for ill-formed and undefined behavior code. The following cases show a few of the variations used:
utilities.tex:any_cast<string&>(y); // error; cannot
g<int>(0); // error, substituting parameter type instantiates \tcode{A<int>}
S<char> s1; // error: no matching constructor
template<> enum A<char>::E : char { echar }; // ill-formed, \tcode{A<char>::E} was instantiated
struct Inner2; // ill-formed, no diagnostic required
// ill-formed, no diagnostic required: the two expressions are functionally equivalent but not equivalent
void A<Y>::B<double>::mf2() { } // ill-formed; \tcode{B<double>} is specialized but
template<class T> void f(T::R); // ill-formed (no diagnostic required), attempt to declare
p->x.j = 99; // undefined: modifies a const subobject
int m = g(false); // undefined behavior due to access of \tcode{x.n} outside its lifetime
C().C::~C(); // undefined behavior: temporary of type \tcode{C} destroyed twice
pb->f(); // undefined behavior, lifetime of \tcode{*pb} has ended
Suggestion: Change all to either of the following as appropriate:
// ill-formed, no diagnostic required: <explanation>
// error: <explanation>
// undefined behavior: <explanation>
where : <explanation> can be omitted if it is clear from the surrounding text.
This does not apply in compatibility.tex, where we should stick with:
f(u8"text"); // ill-formed; previously well-formed