[PATCH] D33333: Emit warning when throw exception in destruct or dealloc functions which has a (possible implicit) noexcept specifier

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


================
Comment at: test/SemaCXX/warn-throw-out-noexcept-func.cpp:27
+}
+
+struct N : A {
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jyu2 wrote:
> aaron.ballman wrote:
> > Can you add a test case like:
> > ```
> > struct Throws {
> >   ~Throws() noexcept(false);
> > };
> > 
> > struct ShouldDiagnose {
> >   Throws T;
> >   ~ShouldDiagnose() {}
> > };
> > ```
> > I would expect `~ShouldDiagnose()` to be diagnosed as allowing exceptions to escape because of the destructor for `Throws`.
> In C++11, destructors are implicitly throw() unless any member or base of the type has a destructor with a different exception specification.
> 
> In the case of:
> struct Throws {
>   ~Throws() noexcept(false);
> };
> 
> struct ShouldDiagnose {
>   Throws T;
>   ~ShouldDiagnose() {}
> };
> 
> You should not see diagnose for   ~ShouldDiagnose() , since   ShouldDiagnose has a member ofr Throws which has destructor with noexcept(false); therefor
>   ~ShouldDiagnose has  noexcept(false).
> 
> But I add test case which remove (false) part.
Good point! A test case with `noexcept(false)` would be handy as would one where `~ShouldDiagnose()` is marked `noexcept(true)` explicitly rather than picking up the `noexcept(false)` implicitly.


https://reviews.llvm.org/D33333