https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93386
Bug ID: 93386
Summary: Missing a const qualifier in the type denoted by
decltype((r))
Product: gcc
Version: 9.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: kyle.show910 at gmail dot com
Target Milestone: ---
According to the standard
timsong-cpp.github.io/cppwp/n4659/expr.prim.lambda.capture#14, we should have
the following:
void f3() {
float x, &r = x;
[=] {
decltype(x) y1; // y1 has type float
decltype((x)) y2 = y1; // y2 has type float const& because this lambda is
not mutable and x is an lvalue
decltype(r) r1 = y1; // r1 has type float& (transformation not
considered)
decltype((r)) r2 = y2; // r2 has type float const&
};
}
but we have this:
void f3() {
float x, &r = x;
[=] {
decltype(x) y1; // y1 has type float
decltype((x)) y2 = y1; // y2 has type float const&
decltype(r) r1 = y1; // r1 has type float&
decltype((r)) r2 = y2; // r2 has type float&
};
}
https://godbolt.org/z/sYXzzn
https://godbolt.org/z/unpxwV
The type denoted by decltype((r)) where r is a reference and decltype occurs
inside a const member function doesn’t contain a const qualifier.
