2 ms·

Mangling is mentioned in the standard. In this case though the underlying reason is that its part of the type (system) not because of the mangle specifically.

• Dylan16807 3y ago
  > Mangling is mentioned in the standard. Forgive me, but can you be clearer than "mentioned"? Is the mangling required to contain template parameters for return types? > In this case though the underlying reason is that its part of the type (system) not because of the mangle specifically. I'm not sure. The compiler knows it will always be the same type, so under many uses of this function I could easily imagine a compiler that doesn't actually fill in .value until runtime.
  • mhh__ 3y ago
    Mangling isn't technically required as per se but it's by far the most common approach (basically a local minimum in terms of cost) I think this subset of C++ templates is probably undecidable still.
  • jcelerier 3y ago
    > Forgive me, but can you be clearer than "mentioned"? Is the mangling required to contain template parameters for return types? The mangling will contain template parameters, as you can have: foo.hpp template<typename T> T f(); foo.cpp template<> int f<int>() { return 123; } template<> float f<float>() { return 123; } bar.cpp std::cout << f<int>(); and the right function has to be found. demo: https://gcc.godbolt.org/z/rMjYoEzaK https://gcc.godbolt.org/z/rMjYoEzaK
    • Dylan16807 3y ago
      Sorry, I meant parameters that only are being returned, and not passed in. So in the example several layers above, T uniquely identifies the function. I don't see any need to involve std::integral_constant<int, x> in the mangling.
      • jcelerier 3y ago
        long story short: https://stackoverflow.com/questions/30057635/why-is-the-return-type-of-c-function-template-instantiations-included-in-the-m https://stackoverflow.com/questions/30057635/why-is-the-retu...