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// RUN: %clang_cc1 -std=c++14 -verify=expected,cxx14 -fsyntax-only -Wshadow -D AVOID %s
// RUN: %clang_cc1 -std=c++14 -verify=expected,cxx14 -fsyntax-only -Wshadow -Wshadow-uncaptured-local %s
// RUN: %clang_cc1 -std=c++14 -verify=expected,cxx14 -fsyntax-only -Wshadow-all %s
// RUN: %clang_cc1 -std=c++17 -verify -fsyntax-only -Wshadow-all %s
// RUN: %clang_cc1 -std=c++20 -verify -fsyntax-only -Wshadow-all %s
void foo(int param) { // expected-note 1+ {{previous declaration is here}}
int var = 0; // expected-note 1+ {{previous declaration is here}}
// Avoid warnings for variables that aren't implicitly captured.
{
#ifdef AVOID
auto f1 = [=] { int var = 1; }; // no warning
auto f2 = [&] { int var = 2; }; // no warning
auto f3 = [=] (int param) { ; }; // no warning
auto f4 = [&] (int param) { ; }; // no warning
auto f5 = [=] { static int var = 1; }; // no warning
auto f6 = [&] { static int var = 2; }; // no warning
#else
auto f1 = [=] { int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f2 = [&] { int var = 2; }; // expected-warning {{declaration shadows a local variable}}
auto f3 = [=] (int param) { ; }; // expected-warning {{declaration shadows a local variable}}
auto f4 = [&] (int param) { ; }; // expected-warning {{declaration shadows a local variable}}
auto f5 = [=] { static int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f6 = [&] { static int var = 2; }; // expected-warning {{declaration shadows a local variable}}
#endif
}
// Warn for variables that are implicitly captured.
{
auto f1 = [=] () {
{
int var = 1; // expected-warning {{declaration shadows a local variable}}
}
int x = var; // expected-note {{variable 'var' is captured here}}
};
auto f2 = [&]
#ifdef AVOID
(int param) {
#else
(int param) { // expected-warning {{declaration shadows a local variable}}
#endif
int x = var; // expected-note {{variable 'var' is captured here}}
int var = param; // expected-warning {{declaration shadows a local variable}}
};
}
// Warn for variables that are explicitly captured when a lambda has a default
// capture specifier.
{
auto f1 = [=, &var] () { // expected-note {{variable 'var' is captured here}}
int x = param; // expected-note {{variable 'param' is captured here}}
int var = 0; // expected-warning {{declaration shadows a local variable}}
int param = 0; // expected-warning {{declaration shadows a local variable}}
};
}
// Warn normally inside of lambdas.
auto l1 = [] { // expected-note {{previous declaration is here}}
int x = 1; // expected-note {{previous declaration is here}}
{ int x = 2; } // expected-warning {{declaration shadows a local variable}}
};
auto l2 = [] (int x) { // expected-note {{previous declaration is here}}
{ int x = 1; } // expected-warning {{declaration shadows a local variable}}
};
// Avoid warnings for variables that aren't explicitly captured.
{
#ifdef AVOID
auto f1 = [] { int var = 1; }; // no warning
auto f2 = [] (int param) { ; }; // no warning
auto f3 = [param] () { int var = 1; }; // no warning
auto f4 = [var] (int param) { ; }; // no warning
auto f5 = [param] () { static int var = 1; }; // no warning
auto f6 = [] { static int var = 1; }; // no warning
#else
auto f1 = [] { int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f2 = [] (int param) { ; }; // expected-warning {{declaration shadows a local variable}}
auto f3 = [param] () { int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f4 = [var] (int param) { ; }; // expected-warning {{declaration shadows a local variable}}
auto f5 = [param] () { static int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f6 = [] { static int var = 1; }; // expected-warning {{declaration shadows a local variable}}
#endif
};
// Warn for variables that are explicitly captured.
{
auto f1 = [var] () { // expected-note {{variable 'var' is explicitly captured here}}
int var = 1; // expected-warning {{declaration shadows a local variable}}
};
auto f2 = [param] // expected-note {{variable 'param' is explicitly captured here}}
(int param) { ; }; // expected-error {{a lambda parameter cannot shadow an explicitly captured entity}}
}
// Warn for variables defined in the capture list.
auto l3 = [z = var] { // expected-note {{previous declaration is here}}
#ifdef AVOID
int var = 1; // no warning
#else
int var = 1; // expected-warning {{declaration shadows a local variable}}
#endif
{ int z = 1; } // expected-warning {{declaration shadows a local variable}}
};
#ifdef AVOID
auto l4 = [var = param] (int param) { ; }; // no warning
#else
auto l4 = [var = param](int param) { ; }; // expected-warning 2{{declaration shadows a local variable}}
#endif
// Make sure that inner lambdas work as well.
auto l5 = [var, l1] { // expected-note {{variable 'l1' is explicitly captured here}}
auto l1 = [] { // expected-warning {{declaration shadows a local variable}}
#ifdef AVOID
int var = 1; // no warning
#else
int var = 1; // expected-warning {{declaration shadows a local variable}}
#endif
};
#ifdef AVOID
auto f1 = [] { int var = 1; }; // no warning
auto f2 = [=] { int var = 1; }; // no warning
#else
auto f1 = [] { int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f2 = [=] { int var = 1; }; // expected-warning {{declaration shadows a local variable}}
#endif
auto f3 = [var] // expected-note {{variable 'var' is explicitly captured here}}
{ int var = 1; }; // expected-warning {{declaration shadows a local variable}}
auto f4 = [&] {
int x = var; // expected-note {{variable 'var' is captured here}}
int var = 2; // expected-warning {{declaration shadows a local variable}}
};
};
auto l6 = [&] {
auto f1 = [param] { // expected-note {{variable 'param' is explicitly captured here}}
int param = 0; // expected-warning {{declaration shadows a local variable}}
};
};
auto l7 = [&] {
auto f1 = [param] { // expected-note {{variable 'param' is explicitly captured here}}
static int param = 0; // expected-warning {{declaration shadows a local variable}}
};
};
// Generic lambda arguments should work.
#ifdef AVOID
auto g1 = [](auto param) { ; }; // no warning
auto g2 = [=](auto param) { ; }; // no warning
#else
auto g1 = [](auto param) { ; }; // expected-warning {{declaration shadows a local variable}}
auto g2 = [=](auto param) { ; }; // expected-warning {{declaration shadows a local variable}}
#endif
auto g3 = [param] // expected-note {{variable 'param' is explicitly captured here}}
(auto param) { ; }; // expected-error {{a lambda parameter cannot shadow an explicitly captured entity}}
}
void avoidWarningWhenRedefining() {
int a = 1;
auto l = [b = a] { // expected-note {{previous definition is here}}
// Don't warn on redefinitions.
int b = 0; // expected-error {{redefinition of 'b'}}
};
}
namespace GH61105 {
void f() {
int y = 0;
int x = 0;
#if __cplusplus >= 202002L
auto l1 = [y]<typename y>(y) { return 0; }; // expected-error {{declaration of 'y' shadows template parameter}} \
// expected-note {{template parameter is declared here}}
auto l2 = [=]<typename y>() { int a = y; return 0; }; // expected-error {{'y' does not refer to a value}} \
// expected-note {{declared here}}
auto l3 = [&, y]<typename y, typename>(y) { int a = x; return 0; }; // expected-error {{declaration of 'y' shadows template parameter}} \
// expected-note {{template parameter is declared here}}
auto l4 = [x, y]<typename y, int x>() { return 0; }; // expected-error {{declaration of 'y' shadows template parameter}} \
// expected-error {{declaration of 'x' shadows template parameter}} \
// expected-note 2{{template parameter is declared here}}
auto l5 = []<typename y>(y) { return 0; }; // No diagnostic
#endif
}
}
namespace GH71976 {
#ifdef AVOID
struct A {
int b = 5;
int foo() {
return [b = b]() { return b; }(); // no -Wshadow diagnostic, init-capture does not shadow b due to not capturing this
}
};
struct B {
int a;
void foo() {
auto b = [a = this->a] {}; // no -Wshadow diagnostic, init-capture does not shadow a due to not capturing his
}
};
struct C {
int b = 5;
int foo() {
return [a = b]() {
return [=, b = a]() { // no -Wshadow diagnostic, init-capture does not shadow b due to outer lambda
return b;
}();
}();
}
};
#else
struct A {
int b = 5; // expected-note {{previous}}
int foo() {
return [b = b]() { return b; }(); // expected-warning {{declaration shadows a field}}
}
};
struct B {
int a; // expected-note {{previous}}
void foo() {
auto b = [a = this->a] {}; // expected-warning {{declaration shadows a field}}
}
};
struct C {
int b = 5; // expected-note {{previous}}
int foo() {
return [a = b]() {
return [=, b = a]() { // expected-warning {{declaration shadows a field}}
return b;
}();
}();
}
};
struct D {
int b = 5; // expected-note {{previous}}
int foo() {
return [b = b, this]() { return b; }(); // expected-warning {{declaration shadows a field}}
}
};
struct E {
int b = 5;
int foo() {
return [a = b]() { // expected-note {{previous}}
return [=, a = a]() { // expected-warning {{shadows a local}}
return a;
}();
}();
}
};
#endif
struct S {
int a ;
};
int foo() {
auto [a] = S{0}; // expected-note {{previous}} \
// cxx14-warning {{decomposition declarations are a C++17 extension}}
[a = a] () { // expected-warning {{declaration shadows a structured binding}}
}();
}
}
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