https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102538
Patrick Palka <ppalka at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |ppalka at gcc dot gnu.org
--- Comment #4 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Analogous constexpr testcase:
struct X { union { char r8[8]; int r32[2]; }; };
struct Y { X v; };
constexpr Y x = { { .r32 = { 5, 6 } } };
static_assert(x.v.r32[0] == 5 && x.v.r32[1] == 6);
The error is perhaps insightful:
<stdin>:4:31: error: non-constant condition for static assertion
<stdin>:4:31: error: accessing ‘X::<unnamed union>::r32’ member instead of
initialized ‘X::<unnamed union>::r8’ member in constant expression
