https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97221
Bug ID: 97221
Summary: Returning an array unexpectedly favors const overload
in return value's constructor
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: blubban at gmail dot com
Target Milestone: ---
struct string {
const char * m;
template<int N> string(const char (&str)[N]) { m = "CONST"; }
template<int N> string(char (&str)[N]) { m = "MUT"; }
};
string foo()
{
char bar[8];
return bar;
}
With Clang 10.0.1 -O2 -std=c++11, this returns "MUT".
With GCC 10.2 -O2 -std=c++98, this returns "MUT".
With GCC 7.5 -O2 -std=c++11, this returns "MUT".
With GCC 10.2 -O2 -std=c++11, this returns "CONST".
This one should give same result for every configuration, or at least throw a
warning from -Wc++11-compat, right?
Compiler Explorer: https://godbolt.org/z/r3Yo64
(Context: I encountered this when trying to make my string class distinguish
between string literals and char arrays/pointers, and call sizeof instead of
strlen for the former.)
