https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104620
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Reduced testcase for -std=c++23
consteval int foo (int x) { return x; }
consteval int bar () { return 2; }
template <typename T>
constexpr int
qux (int x)
{
int r = 0;
if consteval
{
r += 2 * bar ();
}
else
{
r += foo (8 * x); // { dg-error "is not a constant expression" }
}
if ! consteval
{
r += foo (32 * x);// { dg-error "is not a constant expression" }
}
if consteval
{
r += 32 * bar ();
}
return r;
}
The intent of the testcase was to test whether we catch at least some of the
non-dependent consteval calls already during template parsing and so regardless
of whether we actually instantiate them or not.
Worst case it will be diagnosed during instantiation, sure.
But x is not type nor value dependent and neither is 8 * x nor 32 * x.
And make_args_non_dependent calls build_non_dependent_arg which will not wrap
say x or 8, but does wrap x * 8 even when both arguments have integral types.
So, either build_non_dependent_arg should be made smarter and not wrap even
simple arithmetics etc. where no C++ template-ish trees appear inside of it and
everything is like in normal non-template-ish code, or we should reconsider
the r12-7264 case because clearly often we can handle NON_DEPENDENT_EXPR just
fine.
