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From: "raffael at casagrande dot ch" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/112307] Segmentation fault with -O1
 -fcode-hoisting
Date: Fri, 08 Mar 2024 12:58:57 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112307

--- Comment #7 from Raffael Casagrande <raffael at casagrande dot ch> ---
@Jonathan Wakely Thanks very much for the detailed analysis. But there is o=
ne
point which I don't understand:

> BUT, the self-referential pointer is set to the address of the range_ mem=
ber=20
> before the return value is copied, and so goes out of scope when that obj=
ect
> is copied via registers and then copied again into the automatic variable
> in main().


I can't follow/understand how Next() is called before the return value is
copied.
If we look at the constructor of EnumeratorRange, we see that `enumerator_`=
 is
initialized before end_reached_.

And afterwards the enumerator_ is not moved/copied anymore because of copy
elision? This can be verified by adding some extra print statements to the
copy/move constructor of Enumerator.=