https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104513
Bug ID: 104513
Summary: [12 Regression] goto cdtor_label failures on arm since
r12-5256
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jakub at gcc dot gnu.org
Target Milestone: ---
struct A {
int a1;
short a2;
short a3;
long a4;
constexpr A() : a1(), a2(), a3(), a4() { return; }
};
is rejected since r12-5256-g37326651b439bac55d96fb5a43f4daf25e401eda
on arm with:
mptPathString.ii: In constructor ‘constexpr A::A()’:
mptPathString.ii:6:44: error: ‘goto’ is not a constant expression
6 | constexpr A() : a1(), a2(), a3(), a4() { return; }
| ^~~~~~
for -std=c++14 and higher.
Also,
struct S { constexpr S (int x) : s (x) {} constexpr ~S () { s = 5; return; s =
6; } int s; };
constexpr S s = 42;
is rejected with -std=c++20 and higher on all arches incorrectly, but this one
for much longer (GCC 10+).
finish_return_stmt does:
if (DECL_DESTRUCTOR_P (current_function_decl)
|| (DECL_CONSTRUCTOR_P (current_function_decl)
&& targetm.cxx.cdtor_returns_this ()))
{
/* Similarly, all destructors must run destructors for
base-classes before returning. So, all returns in a
destructor get sent to the DTOR_LABEL; finish_function emits
code to return a value there. */
return finish_goto_stmt (cdtor_label);
}
and so I think we need to mark the goto or label somehow to tell
potential_constant_expression that this is an artificial goto which is ok.
