llvm-project/clang/test/SemaCXX/uninit-variables.cpp

153 lines
3.5 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -Wuninitialized -fsyntax-only -fcxx-exceptions %s -verify -std=c++1y
// Stub out types for 'typeid' to work.
namespace std { class type_info {}; }
int test1_aux(int &x);
int test1() {
int x;
test1_aux(x);
return x; // no-warning
}
int test2_aux() {
int x;
int &y = x;
return x; // no-warning
}
// Don't warn on unevaluated contexts.
void unevaluated_tests() {
int x;
(void)sizeof(x);
(void)typeid(x);
}
// Warn for glvalue arguments to typeid whose type is polymorphic.
struct A { virtual ~A() {} };
void polymorphic_test() {
A *a; // expected-note{{initialize the variable 'a' to silence this warning}}
(void)typeid(*a); // expected-warning{{variable 'a' is uninitialized when used here}}
}
// Handle cases where the CFG may constant fold some branches, thus
// mitigating the need for some path-sensitivity in the analysis.
unsigned test3_aux();
unsigned test3() {
unsigned x = 0;
const bool flag = true;
if (flag && (x = test3_aux()) == 0) {
return x;
}
return x;
}
unsigned test3_b() {
unsigned x ;
const bool flag = true;
if (flag && (x = test3_aux()) == 0) {
x = 1;
}
return x; // no-warning
}
unsigned test3_c() {
unsigned x; // expected-note{{initialize the variable 'x' to silence this warning}}
const bool flag = false;
if (flag && (x = test3_aux()) == 0) {
x = 1;
}
return x; // expected-warning{{variable 'x' is uninitialized when used here}}
}
enum test4_A {
test4_A_a, test_4_A_b
};
test4_A test4() {
test4_A a; // expected-note{{variable 'a' is declared here}}
return a; // expected-warning{{variable 'a' is uninitialized when used here}}
}
// Test variables getting invalidated by function calls with reference arguments
// *AND* there are multiple invalidated arguments.
void test5_aux(int &, int &);
int test5() {
int x, y;
test5_aux(x, y);
return x + y; // no-warning
}
// This test previously crashed Sema.
class Rdar9188004A {
public:
virtual ~Rdar9188004A();
};
template< typename T > class Rdar9188004B : public Rdar9188004A {
virtual double *foo(Rdar9188004B *next) const {
double *values = next->foo(0);
try {
}
catch(double e) {
values[0] = e;
}
return 0;
}
};
class Rdar9188004C : public Rdar9188004B<Rdar9188004A> {
virtual void bar(void) const;
};
void Rdar9188004C::bar(void) const {}
// Don't warn about uninitialized variables in unreachable code.
void PR9625() {
if (false) {
int x;
(void)static_cast<float>(x); // no-warning
}
}
// Don't warn about variables declared in "catch"
void RDar9251392_bar(const char *msg);
void RDar9251392() {
try {
throw "hi";
}
catch (const char* msg) {
RDar9251392_bar(msg); // no-warning
}
}
// Test handling of "no-op" casts.
void test_noop_cast()
{
int x = 1;
int y = (int&)x; // no-warning
}
void test_noop_cast2() {
int x; // expected-note {{initialize the variable 'x' to silence this warning}}
int y = (int&)x; // expected-warning {{uninitialized when used here}}
}
// Test handling of bit casts.
void test_bitcasts() {
int x = 1;
int y = (float &)x; // no-warning
}
void test_bitcasts_2() {
int x; // expected-note {{initialize the variable 'x' to silence this warning}}
int y = (float &)x; // expected-warning {{uninitialized when used here}}
}
void consume_const_ref(const int &n);
int test_const_ref() {
int n; // expected-note {{variable}}
consume_const_ref(n);
return n; // expected-warning {{uninitialized when used here}}
}
// Don't crash here.
auto PR19996 = [a=0]{int t; return a;};