1// RUN: %clang_cc1 -fsyntax-only -verify -std=c++1y %s 2 3// expected-no-diagnostics 4 5// C++11 [basic.link]p6: 6// The name of a function declared in block scope and the name 7// of a variable declared by a block scope extern declaration 8// have linkage. If there is a visible declaration of an entity 9// with linkage having the same name and type, ignoring entities 10// declared outside the innermost enclosing namespace scope, the 11// block scope declaration declares that same entity and 12// receives the linkage of the previous declaration. 13 14extern int same_entity; 15constexpr int *get1() { 16 int same_entity = 0; // not the same entity 17 { 18 extern int same_entity; 19 return &same_entity; 20 } 21} 22static_assert(get1() == &same_entity, "failed to find previous decl"); 23 24static int same_entity_2[3]; 25constexpr int *get2() { 26 // This is a redeclaration of the same entity, even though it doesn't 27 // inherit the type of the prior declaration. 28 extern int same_entity_2[]; 29 return same_entity_2; 30} 31static_assert(get2() == same_entity_2, "failed to find previous decl"); 32 33static int different_entities; 34constexpr int *get3() { 35 int different_entities = 0; 36 { 37 // FIXME: This is not a redeclaration of the prior entity, because 38 // it is not visible here. Under DR426, this is ill-formed, and without 39 // it, the static_assert below should fail. 40 extern int different_entities; 41 return &different_entities; 42 } 43} 44static_assert(get3() == &different_entities, "failed to find previous decl"); 45