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// RUN: %clang_analyze_cc1 -Wno-unused-value -std=c++14 -verify %s -triple x86_64-pc-linux-gnu \
// RUN: -analyzer-checker=core,debug.ExprInspection,alpha.core.PointerArithm
// RUN: %clang_analyze_cc1 -Wno-unused-value -std=c++14 -verify %s -triple x86_64-pc-linux-gnu \
// RUN: -analyzer-config support-symbolic-integer-casts=true \
// RUN: -analyzer-checker=core,debug.ExprInspection,alpha.core.PointerArithm
template <typename T> void clang_analyzer_dump(T);
struct X {
int *p;
int zero;
void foo () {
reset(p - 1);
}
void reset(int *in) {
while (in != p) // Loop must be entered.
zero = 1;
}
};
int test (int *in) {
X littleX;
littleX.zero = 0;
littleX.p = in;
littleX.foo();
return 5/littleX.zero; // no-warning
}
class Base {};
class Derived : public Base {};
void checkPolymorphicUse() {
Derived d[10];
Base *p = d;
++p; // expected-warning{{Pointer arithmetic on a pointer to base class is dangerous}}
}
void checkBitCasts() {
long l;
char *p = (char*)&l;
p = p+2;
}
void checkBasicarithmetic(int i) {
int t[10];
int *p = t;
++p;
int a = 5;
p = &a;
++p; // expected-warning{{Pointer arithmetic on non-array variables relies on memory layout, which is dangerous}}
p = p + 2; // expected-warning{{}}
p = 2 + p; // expected-warning{{}}
p += 2; // expected-warning{{}}
a += p[2]; // expected-warning{{}}
p = i*0 + p;
p = p + i*0;
p += i*0;
}
void checkArithOnSymbolic(int*p) {
++p;
p = p + 2;
p = 2 + p;
p += 2;
(void)p[2];
}
struct S {
int t[10];
};
void arrayInStruct() {
S s;
int * p = s.t;
++p;
S *sp = new S;
p = sp->t;
++p;
delete sp;
}
void checkNew() {
int *p = new int;
p[1] = 1; // expected-warning{{}}
}
void InitState(int* state) {
state[1] = 1; // expected-warning{{}}
}
int* getArray(int size) {
if (size == 0)
return new int;
return new int[5];
}
void checkConditionalArray() {
int* maybeArray = getArray(0);
InitState(maybeArray);
}
void checkMultiDimansionalArray() {
int a[5][5];
*(*(a+1)+2) = 2;
}
unsigned ptrSubtractionNoCrash(char *Begin, char *End) {
auto N = End - Begin;
if (Begin)
return 0;
return N;
}
// Bug 34309
bool ptrAsIntegerSubtractionNoCrash(__UINTPTR_TYPE__ x, char *p) {
__UINTPTR_TYPE__ y = (__UINTPTR_TYPE__)p - 1;
return y == x;
}
// Bug 34374
bool integerAsPtrSubtractionNoCrash(char *p, __UINTPTR_TYPE__ m) {
auto n = p - reinterpret_cast<char*>((__UINTPTR_TYPE__)1);
return n == m;
}
namespace Bug_55934 {
struct header {
unsigned a : 1;
unsigned b : 1;
};
struct parse_t {
unsigned bits0 : 1;
unsigned bits2 : 2; // <-- header
unsigned bits4 : 4;
};
int parse(parse_t *p) {
unsigned copy = p->bits2;
clang_analyzer_dump(copy);
// expected-warning@-1 {{reg_$1<unsigned int Element{SymRegion{reg_$0<parse_t * p>},0 S64b,struct Bug_55934::parse_t}.bits2>}}
header *bits = (header *)©
clang_analyzer_dump(bits->b);
// expected-warning@-1 {{derived_$2{reg_$1<unsigned int Element{SymRegion{reg_$0<parse_t * p>},0 S64b,struct Bug_55934::parse_t}.bits2>,Element{copy,0 S64b,struct Bug_55934::header}.b}}}
return bits->b; // no-warning
}
} // namespace Bug_55934
void LValueToRValueBitCast_dumps(void *p, char (*array)[8]) {
clang_analyzer_dump(p);
clang_analyzer_dump(array);
// expected-warning@-2 {{&SymRegion{reg_$0<void * p>}}}
// expected-warning@-2 {{&SymRegion{reg_$1<char (*)[8] array>}}}
clang_analyzer_dump((unsigned long)p);
clang_analyzer_dump(__builtin_bit_cast(unsigned long, p));
// expected-warning@-2 {{&SymRegion{reg_$0<void * p>} [as 64 bit integer]}}
// expected-warning@-2 {{&SymRegion{reg_$0<void * p>} [as 64 bit integer]}}
clang_analyzer_dump((unsigned long)array);
clang_analyzer_dump(__builtin_bit_cast(unsigned long, array));
// expected-warning@-2 {{&SymRegion{reg_$1<char (*)[8] array>} [as 64 bit integer]}}
// expected-warning@-2 {{&SymRegion{reg_$1<char (*)[8] array>} [as 64 bit integer]}}
}
unsigned long ptr_arithmetic(void *p) {
return __builtin_bit_cast(unsigned long, p) + 1; // no-crash
}
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