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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/107622] Missing optimization of switch-statement
Date: Fri, 02 Dec 2022 14:45:31 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107622

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
If you use enum with fixed underlying type, then all the values of the
underlying type are valid, even with -fstrict-enums.  Otherwise
namespace std {
enum class byte : unsigned char {};
}
couldn't work properly.  Otherwise, with -fstrict-enums, enum { A, B, C } c=
an
have
values 0, 1, 2, 3 and without -fstrict-enums all the values of the underlyi=
ng
type.
See https://eel.is/c++draft/dcl.enum#8 for more details.
So, except for the https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107622#c4=
 g
case where
we should have optimized it into constant I don't see any missed optimizati=
on
here.=