lifetime-extension.mm
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// RUN: %clang_analyze_cc1 -Wno-unused -std=c++11 -analyzer-checker=core,debug.ExprInspection -verify %s
// RUN: %clang_analyze_cc1 -Wno-unused -std=c++17 -analyzer-checker=core,debug.ExprInspection -verify %s
// RUN: %clang_analyze_cc1 -Wno-unused -std=c++11 -analyzer-checker=core,debug.ExprInspection -DMOVES -verify %s
// RUN: %clang_analyze_cc1 -Wno-unused -std=c++17 -analyzer-checker=core,debug.ExprInspection -DMOVES -verify %s
void clang_analyzer_eval(bool);
void clang_analyzer_checkInlined(bool);
template <typename T> struct AddressVector {
T *buf[10];
int len;
AddressVector() : len(0) {}
void push(T *t) {
buf[len] = t;
++len;
}
};
class C {
AddressVector<C> &v;
public:
C(AddressVector<C> &v) : v(v) { v.push(this); }
~C() { v.push(this); }
#ifdef MOVES
C(C &&c) : v(c.v) { v.push(this); }
#endif
// Note how return-statements prefer move-constructors when available.
C(const C &c) : v(c.v) {
#ifdef MOVES
clang_analyzer_checkInlined(false); // no-warning
#else
v.push(this);
#endif
} // no-warning
};
@interface NSObject {}
@end;
@interface Foo: NSObject {}
-(C) make: (AddressVector<C> &)v;
@end
@implementation Foo
-(C) make: (AddressVector<C> &)v {
return C(v);
}
@end
void testReturnByValueFromMessage(Foo *foo) {
AddressVector<C> v;
{
const C &c = [foo make: v];
}
// 0. Construct the return value of -make (copy/move elided) and
// lifetime-extend it directly via reference 'c',
// 1. Destroy the temporary lifetime-extended by 'c'.
clang_analyzer_eval(v.len == 2); // expected-warning{{TRUE}}
clang_analyzer_eval(v.buf[0] == v.buf[1]); // expected-warning{{TRUE}}
}