https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64665
Bug ID: 64665
Summary: Overload resolution not working with
std::initializer_list and bool
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: duncan.forster at mac dot com
Created attachment 34482
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34482&action=edit
gcc -v
Test case.
#include
#include
void Test1(const bool arg)
{
std::cout << "Right[" << arg << "] (standard conversion sequence)" <<
std::endl;
}
void Test1(const std::string arg)
{
std::cout << "Wrong[" << arg.size() << "] (user-defined conversion
sequence)" << std::endl;
}
void Test2(const int arg)
{
std::cout << "Wrong[" << arg << "] (no conversion, doesn't initializes
std::initializer_list)" << std::endl;
}
void Test2(const std::initializer_list arg)
{
std::cout << "Right[" << arg.size() << "] (no conversion, initializes
std::initializer_list)" << std::endl;
}
struct S
{
S(int _a) : a(_a){}
int getA() const { return a; }
private:
int a;
};
void Test3(const int arg)
{
std::cout << "Right[" << arg << "] (standard conversion sequence)" <<
std::endl;
}
void Test3(const S arg)
{
std::cout << "Wrong[" << arg.getA() << "] (user-defined conversion
sequence)" << std::endl;
}
void Test4(const bool arg)
{
std::cout << "Right[" << arg << "] (standard conversion sequence)" <<
std::endl;
}
void Test4(const std::initializer_list arg)
{
std::cout << "Wrong[" << arg.size() << "] (user-defined conversion
sequence)" << std::endl;
}
int main (int /*argc*/, char * const /*argv*/[])
{
Test1({"false"});
Test2({123});
Test3({456});
Test4({"false"});
return 0;
}
GCC should print:
Right[1] (standard conversion sequence)
Right[1] (no conversion, initializes std::initializer_list)
Right[456] (standard conversion sequence)
Right[1] (standard conversion sequence)
GCC prints this instead:
Right[1] (standard conversion sequence)
Right[1] (no conversion, initializes std::initializer_list)
Right[456] (standard conversion sequence)
Wrong[1] (user-defined conversion sequence)
Here are the two conversion sequences for Test4:
{const char[6]} -> {const char*} -> {bool} (standard conversion sequence)
{const char[6]} -> {const char*} -> {std::string::ctor} (user-defined
conversion sequence)
The standard conversion sequence should be preferred over a user-defined
conversion sequence.
