https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108993
panigstein at hotmail dot com changed:
What |Removed |Added
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CC| |panigstein at hotmail dot com
--- Comment #2 from panigstein at hotmail dot com ---
(In reply to Andrew Pinski from comment #1)
> Hmm,
> I noticed that since GCC 7 with -std=c++17, the b.x is not initialized at
> all. So the question I have is there a difference between C++ standards here?
>
> Note the issue is we call Base's constructor after doing the zero
> initialization and the Base's constructor has a clobber in it which I think
> is correct.
>
> This is all front-end generation and not exactly related to the
> optimizations directly.
There is no difference between C++ standards in this respect. For a class that
has a defaulted default constructor (Derived), value-initialization consists of
zero-initialization followed by default-initialization. The clobbering of the
Base sub-object is incorrect here and makes the implementation of
value-initialization non-conforming.
