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| // RUN: %clang_cc1 -fsyntax-only -verify -std=c++1y %s
// expected-no-diagnostics
// C++11 [basic.link]p6:
// The name of a function declared in block scope and the name
// of a variable declared by a block scope extern declaration
// have linkage. If there is a visible declaration of an entity
// with linkage having the same name and type, ignoring entities
// declared outside the innermost enclosing namespace scope, the
// block scope declaration declares that same entity and
// receives the linkage of the previous declaration.
extern int same_entity;
constexpr int *get1() {
int same_entity = 0; // not the same entity
{
extern int same_entity;
return &same_entity;
}
}
static_assert(get1() == &same_entity, "failed to find previous decl");
static int same_entity_2[3];
constexpr int *get2() {
// This is a redeclaration of the same entity, even though it doesn't
// inherit the type of the prior declaration.
extern int same_entity_2[];
return same_entity_2;
}
static_assert(get2() == same_entity_2, "failed to find previous decl");
static int different_entities;
constexpr int *get3() {
int different_entities = 0;
{
// FIXME: This is not a redeclaration of the prior entity, because
// it is not visible here. Under DR426, this is ill-formed, and without
// it, the static_assert below should fail.
extern int different_entities;
return &different_entities;
}
}
static_assert(get3() == &different_entities, "failed to find previous decl");
|