placement-new.cpp
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// RUN: %clang_analyze_cc1 -std=c++11 %s \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=cplusplus.NewDelete \
// RUN: -analyzer-checker=cplusplus.PlacementNew \
// RUN: -analyzer-output=text -verify \
// RUN: -triple x86_64-unknown-linux-gnu
#include "Inputs/system-header-simulator-cxx.h"
void f() {
short s; // expected-note {{'s' declared without an initial value}}
long *lp = ::new (&s) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 3 {{}}
(void)lp;
}
namespace testArrayNew {
void f() {
short s; // expected-note {{'s' declared without an initial value}}
char *buf = ::new (&s) char[8]; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 3 {{}}
(void)buf;
}
} // namespace testArrayNew
namespace testBufferInOtherFun {
void f(void *place) {
long *lp = ::new (place) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
void g() {
short buf; // expected-note {{'buf' declared without an initial value}}
f(&buf); // expected-note 2 {{}}
}
} // namespace testBufferInOtherFun
namespace testArrayBuffer {
void f(void *place) {
long *lp = ::new (place) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
void g() {
char buf[2]; // expected-note {{'buf' initialized here}}
f(&buf); // expected-note 2 {{}}
}
} // namespace testArrayBuffer
namespace testGlobalPtrAsPlace {
void *gptr = nullptr;
short gs;
void f() {
gptr = &gs; // expected-note {{Value assigned to 'gptr'}}
}
void g() {
f(); // expected-note 2 {{}}
long *lp = ::new (gptr) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testGlobalPtrAsPlace
namespace testRvalue {
short gs;
void *f() {
return &gs;
}
void g() {
long *lp = ::new (f()) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testRvalue
namespace testNoWarning {
void *f();
void g() {
long *lp = ::new (f()) long;
(void)lp;
}
} // namespace testNoWarning
namespace testPtrToArrayAsPlace {
void f() {
//char *st = new char [8];
char buf[3]; // expected-note {{'buf' initialized here}}
void *st = buf; // expected-note {{'st' initialized here}}
long *lp = ::new (st) long; // expected-warning{{Storage provided to placement new is only 3 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testPtrToArrayAsPlace
namespace testPtrToArrayWithOffsetAsPlace {
void f() {
int buf[3]; // expected-note {{'buf' initialized here}}
long *lp = ::new (buf + 2) long; // expected-warning{{Storage provided to placement new is only 4 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testPtrToArrayWithOffsetAsPlace
namespace testZeroSize {
void f() {
int buf[3]; // expected-note {{'buf' initialized here}}
long *lp = ::new (buf + 3) long; // expected-warning{{Storage provided to placement new is only 0 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testZeroSize
namespace testNegativeSize {
void f() {
int buf[3]; // expected-note {{'buf' initialized here}}
long *lp = ::new (buf + 4) long; // expected-warning{{Storage provided to placement new is only -4 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testNegativeSize
namespace testHeapAllocatedBuffer {
void g2() {
char *buf = new char[2]; // expected-note {{'buf' initialized here}}
long *lp = ::new (buf) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testHeapAllocatedBuffer
namespace testMultiDimensionalArray {
void f() {
char buf[2][3]; // expected-note {{'buf' initialized here}}
long *lp = ::new (buf) long; // expected-warning{{Storage provided to placement new is only 6 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testMultiDimensionalArray
namespace testMultiDimensionalArray2 {
void f() {
char buf[2][3]; // expected-note {{'buf' initialized here}}
long *lp = ::new (buf + 1) long; // expected-warning{{Storage provided to placement new is only 3 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testMultiDimensionalArray2
namespace testMultiDimensionalArray3 {
void f() {
char buf[2][3]; // expected-note {{'buf' initialized here}}
long *lp = ::new (&buf[1][1]) long; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)lp;
}
} // namespace testMultiDimensionalArray3
namespace testHierarchy {
struct Base {
char a[2];
};
struct Derived : Base {
char x[2];
int y;
};
void f() {
Base b; // expected-note {{'b' initialized here}}
Derived *dp = ::new (&b) Derived; // expected-warning{{Storage provided to placement new is only 2 bytes, whereas the allocated type requires 8 bytes}} expected-note 1 {{}}
(void)dp;
}
} // namespace testHierarchy
namespace testArrayTypesAllocation {
void f1() {
struct S {
short a;
};
// bad (not enough space).
const unsigned N = 32;
alignas(S) unsigned char buffer1[sizeof(S) * N]; // expected-note {{'buffer1' initialized here}}
::new (buffer1) S[N]; // expected-warning{{Storage provided to placement new is only 64 bytes, whereas the allocated array type requires more space for internal needs}} expected-note 1 {{}}
}
void f2() {
struct S {
short a;
};
// maybe ok but we need to warn.
const unsigned N = 32;
alignas(S) unsigned char buffer2[sizeof(S) * N + sizeof(int)]; // expected-note {{'buffer2' initialized here}}
::new (buffer2) S[N]; // expected-warning{{68 bytes is possibly not enough for array allocation which requires 64 bytes. Current overhead requires the size of 4 bytes}} expected-note 1 {{}}
}
} // namespace testArrayTypesAllocation
namespace testStructAlign {
void f1() {
struct X {
char a[9];
} Xi; // expected-note {{'Xi' initialized here}}
// bad (struct X is aligned to char).
::new (&Xi.a) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f2() {
struct X {
char a;
char b;
long c;
} Xi;
// ok (struct X is aligned to long).
::new (&Xi.a) long;
}
void f3() {
struct X {
char a;
char b;
long c;
} Xi; // expected-note {{'Xi' initialized here}}
// bad (struct X is aligned to long but field 'b' is aligned to 1 because of its offset)
::new (&Xi.b) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f4() {
struct X {
char a;
struct alignas(alignof(short)) Y {
char b;
char c;
} y;
long d;
} Xi; // expected-note {{'Xi' initialized here}}
// bad. 'b' is aligned to short
::new (&Xi.y.b) long; // expected-warning{{Storage type is aligned to 2 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f5() {
short b[10]; // expected-note {{'b' initialized here}}
::new (&b) long; // expected-warning{{Storage type is aligned to 2 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f6() {
short b[10]; // expected-note {{'b' initialized here}}
// bad (same as previous but checks ElementRegion case)
::new (&b[0]) long; // expected-warning{{Storage type is aligned to 2 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f7() {
alignas(alignof(long)) short b[10];
// ok. aligned to long(ok). offset 4*2(ok)
::new (&b[4]) long;
}
void f8() {
alignas(alignof(long)) short b[10]; // expected-note {{'b' initialized here}}
// ok. aligned to long(ok). offset 3*2(ok)
::new (&b[3]) long; // expected-warning{{Storage type is aligned to 6 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f9() {
struct X {
char a;
alignas(alignof(long)) char b[20];
} Xi; // expected-note {{'Xi' initialized here}}
// ok. aligned to long(ok). offset 8*1(ok)
::new (&Xi.b[8]) long;
// bad. aligned to long(ok). offset 1*1(ok)
::new (&Xi.b[1]) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f10() {
struct X {
char a[8];
alignas(2) char b;
} Xi; // expected-note {{'Xi' initialized here}}
// bad (struct X is aligned to 2).
::new (&Xi.a) long; // expected-warning{{Storage type is aligned to 2 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void f11() {
struct X {
char a;
char b;
struct Y {
long c;
} d;
} Xi;
// ok (struct X is aligned to long).
::new (&Xi.a) long;
}
void f12() {
struct alignas(alignof(long)) X {
char a;
char b;
} Xi;
// ok (struct X is aligned to long).
::new (&Xi.a) long;
}
void test13() {
struct Y {
char a[10];
};
struct X {
Y b[10];
} Xi; // expected-note {{'Xi' initialized here}}
// bad. X,A are aligned to 'char'
::new (&Xi.b[0].a) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void test14() {
struct Y {
char a[10];
};
struct alignas(alignof(long)) X {
Y b[10];
} Xi;
// ok. X is aligned to 'long' and field 'a' goes with zero offset
::new (&Xi.b[0].a) long;
}
void test15() {
struct alignas(alignof(long)) Y {
char a[10];
};
struct X {
Y b[10];
} Xi;
// ok. X is aligned to 'long' because it contains struct 'Y' which is aligned to 'long'
::new (&Xi.b[0].a) long;
}
void test16() {
struct alignas(alignof(long)) Y {
char p;
char a[10];
};
struct X {
Y b[10];
} Xi; // expected-note {{'Xi' initialized here}}
// bad. aligned to long(ok). offset 1(bad)
::new (&Xi.b[0].a) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void test17() {
struct alignas(alignof(long)) Y {
char p;
char a[10];
};
struct X {
Y b[10];
} Xi;
// ok. aligned to long(ok). offset 1+7*1(ok)
::new (&Xi.b[0].a[7]) long;
}
void test18() {
struct Y {
char p;
alignas(alignof(long)) char a[10];
};
struct X {
Y b[10];
} Xi; // expected-note {{'Xi' initialized here}}
// ok. aligned to long(ok). offset 8*1(ok)
::new (&Xi.b[0].a[8]) long;
// bad. aligned to long(ok). offset 1(bad)
::new (&Xi.b[0].a[1]) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void test19() {
struct Z {
char p;
char c[10];
};
struct Y {
char p;
Z b[10];
};
struct X {
Y a[10];
} Xi; // expected-note {{'Xi' initialized here}}
// bad. all structures X,Y,Z are aligned to char
::new (&Xi.a[1].b[1].c) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void test20() {
struct Z {
char p;
alignas(alignof(long)) char c[10];
};
struct Y {
char p;
Z b[10];
};
struct X {
Y a[10];
} Xi;
// ok. field 'c' is aligned to 'long'
::new (&Xi.a[1].b[1].c) long;
}
void test21() {
struct Z {
char p;
char c[10];
};
struct Y {
char p;
Z b[10];
};
struct alignas(alignof(long)) X {
Y a[10];
} Xi; // expected-note {{'Xi' initialized here}}
// ok. aligned to long(ok). offset 1+7*1(ok)
::new (&Xi.a[0].b[0].c[7]) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
void test22() {
struct alignas(alignof(long)) Y {
char p;
char a[10][10];
};
struct X {
Y b[10];
} Xi; // expected-note {{'Xi' initialized here}}
// ok. aligned to long(ok). offset ok. 1(field 'a' offset) + 0*10(index '0' * first dimension size '10') + 7*1(index '7')
::new (&Xi.b[0].a[0][7]) long;
// ok. aligned to long(ok). offset ok. 1(field 'a' offset) + 1*10(index '1' * first dimension size '10') + 5*1(index '5')
::new (&Xi.b[0].a[1][5]) long;
// bad. aligned to long(ok). offset ok. 1(field 'a' offset) + 1*10(index '1' * first dimension size '10') + 6*1(index '5')
::new (&Xi.b[0].a[1][6]) long; // expected-warning{{Storage type is aligned to 1 bytes but allocated type is aligned to 8 bytes}} expected-note 1 {{}}
}
} // namespace testStructAlign