Isn't comma operator suppose to honor left-to-right associativity?
When I try it on this test case, it exhibits right-to-left associativity.
#include <iostream>
struct CBI;
struct EC;
struct CET;
struct CBI {
CBI& operator,(const CBI& rhs)
{ return *const_cast<CBI*>(&rhs); }
};
struct EC : CBI {
explicit EC(CET* cet) : cet_(cet)
{}
CET* cet_;
};
struct CET {
CBI& operator,(const CBI& rhs) const
{ return *const_cast<CBI*>(&rhs); }
operator EC&() const
{ return *new EC(const_cast<CET*>(this)); }
};
static const CET&
hello() {
std::cout << "Hello " << std::endl;
return *new CET();
}
static const CET&
world() {
std::cout << "World " << std::endl;
return *new CET();
}
static void
test_comma_operator(CBI&) {
}
int main()
{
test_comma_operator ((
hello(),
world()
));
}
CLANG appears to do it right.
us01odcvde08782> clang++ -g test.cpp
us01odcvde08782> ./a.out
*Hello*
World
us01odcvde08782> g++ -g test.cpp
us01odcvde08782> ./a.out
World
*Hello*
us01odcvde08782>
I was using CentOS6.8 with gcc 6.2. However, trying other versions of GCC
didn't make any difference.
Is this a bug in GCC?
