llvm-project/clang/test/SemaCXX/libcxx_valarray_hack.cpp

33 lines
998 B
C++

// RUN: %clang_cc1 -fsyntax-only %s -std=c++11 -verify
// This is a test for a hack in Clang that works around an issue with libc++'s
// <valarray> implementation. The <valarray> header contains explicit
// instantiations of functions that it declared with the internal_linkage
// attribute, which are ill-formed by [temp.explicit]p13 (and meaningless).
#ifdef BE_THE_HEADER
#pragma GCC system_header
namespace std {
using size_t = __SIZE_TYPE__;
template<typename T> struct valarray {
__attribute__((internal_linkage)) valarray(size_t) {}
__attribute__((internal_linkage)) ~valarray() {}
};
extern template valarray<size_t>::valarray(size_t);
extern template valarray<size_t>::~valarray();
}
#else
#define BE_THE_HEADER
#include "libcxx_valarray_hack.cpp"
template<typename T> struct foo {
__attribute__((internal_linkage)) void x() {};
};
extern template void foo<int>::x(); // expected-error {{explicit instantiation declaration of 'x' with internal linkage}}
#endif