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 14 extern int same_entity; 15 constexpr int *get1() { 16 int same_entity = 0; // not the same entity 17 { 18 extern int same_entity; 19 return &same_entity; 20 } 21 } 22 static_assert(get1() == &same_entity, "failed to find previous decl"); 23 24 static int same_entity_2[3]; 25 constexpr 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 } 31 static_assert(get2() == same_entity_2, "failed to find previous decl"); 32 33 static int different_entities; 34 constexpr 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 } 44 static_assert(get3() == &different_entities, "failed to find previous decl"); 45
