Inheriting operator() from multiple classes doesn't cause ambiguity on overload resolution

[llvmbot]

Bugzilla Link	36226
Version	trunk
OS	Windows NT
Reporter	LLVM Bugzilla Contributor
CC	@DougGregor

Extended Description

The following code snippet (to my knowledge) should be rejected because the overload resolution can't cope with the ambiguity of which operator() to call. This ambiguity is described in [class.member.lookup] section of the C++ standard.

#include <iostream>

using namespace std;

struct IntPrinter
{
    void operator()(int i)
    {
    }
};

class FloatPrinter
{
public:
    void operator()(float f)
    {
    }
};

struct Printer: IntPrinter, FloatPrinter
{
};

int main()
{
    Printer printer;
    printer(55);
    printer(55.1f);
};

The code compiles fine but should fail to compile. It doesn't compile on gcc.

[shafik]

Duplicate of: #22413

[llvmbot]

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