[Bug c++/99452] Inconsistent constinit handling

[nathan at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99452

--- Comment #1 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
Here's another:

using value_t = unsigned long;
unsigned obj;

constinit value_t failed
  = reinterpret_cast<value_t> (&obj) + (11 << 0);

constinit value_t accepted
  = reinterpret_cast<value_t> (&obj) + (11);

bester:309>gcc-current/bin/g++ -c -std=gnu++20 r.ii

r.ii:5:19: error: ‘constinit’ variable ‘failed’ does not have a constant
initializer
    5 | constinit value_t failed
      |                   ^~~~~~
r.ii:6:5: error: conversion from pointer type ‘unsigned int*’ to arithmetic
type ‘value_t’ {aka ‘long unsigned int’} in a constant expression
    6 |   = reinterpret_cast<value_t> (&obj) + (11 << 0);