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| // RUN: %clang_cc1 -fsyntax-only -verify %s
namespace test1 {
extern "C" {
void test1_f() {
void test1_g(int);
}
}
}
int test1_g(int);
namespace test2 {
extern "C" {
void test2_f() {
extern int test2_x; // expected-note {{declared with C language linkage here}}
}
}
}
float test2_x; // expected-error {{declaration of 'test2_x' in global scope conflicts with declaration with C language linkage}}
namespace test3 {
extern "C" {
void test3_f() {
extern int test3_b; // expected-note {{previous declaration is here}}
}
}
extern "C" {
float test3_b; // expected-error {{redefinition of 'test3_b' with a different type: 'float' vs 'int'}}
}
}
namespace N {
extern "C" {
void test4_f() {
extern int test4_b; // expected-note {{declared with C language linkage here}}
}
}
}
static float test4_b; // expected-error {{declaration of 'test4_b' in global scope conflicts with declaration with C language linkage}}
extern "C" {
void test4c_f() {
extern int test4_c; // expected-note {{previous}}
}
}
static float test4_c; // expected-error {{redefinition of 'test4_c' with a different type: 'float' vs 'int'}}
namespace N {
extern "C" {
void test5_f() {
extern int test5_b; // expected-note {{declared with C language linkage here}}
}
}
}
extern "C" {
static float test5_b; // expected-error {{declaration of 'test5_b' in global scope conflicts with declaration with C language linkage}}
}
extern "C" {
void test5c_f() {
extern int test5_c; // expected-note {{previous}}
}
}
extern "C" {
static float test5_c; // expected-error {{redefinition of 'test5_c' with a different type: 'float' vs 'int'}}
}
extern "C" {
void f() {
extern int test6_b;
}
}
namespace foo {
extern "C" {
static float test6_b;
extern float test6_b;
}
}
namespace linkage {
namespace redecl {
extern "C" {
static void linkage_redecl();
static void linkage_redecl(int);
void linkage_redecl(); // ok, still not extern "C"
void linkage_redecl(int); // ok, still not extern "C"
void linkage_redecl(float); // expected-note {{previous}}
void linkage_redecl(double); // expected-error {{conflicting types}}
}
}
namespace from_outer {
void linkage_from_outer_1(); // expected-note {{previous}}
void linkage_from_outer_2(); // expected-note {{previous}}
extern "C" {
void linkage_from_outer_1(int);
void linkage_from_outer_1(); // expected-error {{different language linkage}}
void linkage_from_outer_2(); // expected-error {{different language linkage}}
}
}
namespace mixed {
extern "C" {
void linkage_mixed_1();
static void linkage_mixed_1(int);
static void linkage_mixed_2(int);
void linkage_mixed_2();
}
}
namespace across_scopes {
namespace X {
extern "C" void linkage_across_scopes_f() {
void linkage_across_scopes_g(); // expected-note {{previous}}
}
}
namespace Y {
extern "C" void linkage_across_scopes_g(int); // expected-error {{conflicting}}
}
}
}
int lookup_in_global_f; // expected-note {{here}}
namespace lookup_in_global {
void lookup_in_global_f();
void lookup_in_global_g();
extern "C" {
void lookup_in_global_f(int); // expected-error {{conflicts with declaration in global scope}}
void lookup_in_global_g(int); // expected-note {{here}}
}
}
int lookup_in_global_g; // expected-error {{conflicts with declaration with C language linkage}}
namespace N1 {
extern "C" int different_kind_1; // expected-note {{here}}
extern "C" void different_kind_2(); // expected-note {{here}}
}
namespace N2 {
extern "C" void different_kind_1(); // expected-error {{different kind of symbol}}
extern "C" int different_kind_2; // expected-error {{different kind of symbol}}
}
// We allow all these even though the standard says they are ill-formed.
extern "C" {
struct stat {}; // expected-warning{{empty struct has size 0 in C, size 1 in C++}}
void stat(struct stat);
}
namespace X {
extern "C" {
void stat(struct ::stat);
}
}
int stat(int *p);
void global_fn_vs_extern_c_var_1();
namespace X {
extern "C" int global_fn_vs_extern_c_var_1;
extern "C" int global_fn_vs_extern_c_var_2;
}
void global_fn_vs_extern_c_var_2();
void global_fn_vs_extern_c_fn_1();
namespace X {
extern "C" int global_fn_vs_extern_c_fn_1(int);
extern "C" int global_fn_vs_extern_c_fn_2(int);
}
void global_fn_vs_extern_c_fn_2();
extern "C" void name_with_using_decl_1(int);
namespace using_decl {
void name_with_using_decl_1();
void name_with_using_decl_2();
void name_with_using_decl_3();
}
using using_decl::name_with_using_decl_1;
using using_decl::name_with_using_decl_2;
extern "C" void name_with_using_decl_2(int);
extern "C" void name_with_using_decl_3(int);
using using_decl::name_with_using_decl_3;
// We do not allow a global variable and an extern "C" function to have the same
// name, because such entities may have the same mangled name.
int global_var_vs_extern_c_fn_1; // expected-note {{here}}
namespace X {
extern "C" void global_var_vs_extern_c_fn_1(); // expected-error {{conflicts with declaration in global scope}}
extern "C" void global_var_vs_extern_c_fn_2(); // expected-note {{here}}
}
int global_var_vs_extern_c_fn_2; // expected-error {{conflicts with declaration with C language linkage}}
int global_var_vs_extern_c_var_1; // expected-note {{here}}
namespace X {
extern "C" double global_var_vs_extern_c_var_1; // expected-error {{conflicts with declaration in global scope}}
extern "C" double global_var_vs_extern_c_var_2; // expected-note {{here}}
}
int global_var_vs_extern_c_var_2; // expected-error {{conflicts with declaration with C language linkage}}
template <class T> struct pr5065_n1 {};
extern "C" {
union pr5065_1 {}; // expected-warning{{empty union has size 0 in C, size 1 in C++}}
struct pr5065_2 { int: 0; }; // expected-warning{{struct has size 0 in C, size 1 in C++}}
struct pr5065_3 {}; // expected-warning{{empty struct has size 0 in C, size 1 in C++}}
struct pr5065_4 { // expected-warning{{empty struct has size 0 in C, size 1 in C++}}
struct Inner {}; // expected-warning{{empty struct has size 0 in C, size 1 in C++}}
};
// These should not warn
class pr5065_n3 {};
pr5065_n1<int> pr5065_v;
struct pr5065_n4 { void m() {} };
struct pr5065_n5 : public pr5065_3 {};
struct pr5065_n6 : public virtual pr5065_3 {};
}
struct pr5065_n7 {};
namespace tag_hiding {
namespace namespace_with_injected_name {
class Boo {
friend struct ExternCStruct1;
};
void ExternCStruct4(); // expected-note 2{{candidate}}
}
class Baz {
friend struct ExternCStruct2;
friend void ExternCStruct3();
};
using namespace namespace_with_injected_name;
extern "C" {
struct ExternCStruct1;
struct ExternCStruct2;
struct ExternCStruct3;
struct ExternCStruct4; // expected-note {{candidate}}
}
ExternCStruct1 *p1;
ExternCStruct2 *p2;
ExternCStruct3 *p3;
ExternCStruct4 *p4; // expected-error {{ambiguous}}
extern "C" {
struct ExternCStruct1;
struct ExternCStruct2;
struct ExternCStruct3;
struct ExternCStruct4; // expected-note {{candidate}}
}
ExternCStruct1 *q1 = p1;
ExternCStruct2 *q2 = p2;
ExternCStruct3 *q3 = p3;
ExternCStruct4 *q4 = p4; // expected-error {{ambiguous}}
}
namespace PR35697 {
typedef struct {} *ReturnStruct;
extern "C" ReturnStruct PR35697_f();
extern "C" ReturnStruct PR35697_v;
ReturnStruct PR35697_f();
ReturnStruct PR35697_v;
namespace {
extern "C" ReturnStruct PR35697_f();
extern "C" ReturnStruct PR35697_v;
void q() {
extern ReturnStruct PR35697_f();
extern ReturnStruct PR35697_v;
}
}
}
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