Files
clang-p2996/clang/test/Analysis/diagnostics/no-store-func-path-notes.c
George Karpenkov e15451a9c0 [analyzer] mark returns of functions where the region passed as parameter was not initialized
In the wild, many cases of null pointer dereference, or uninitialized
value read occur because the value was meant to be initialized by the
inlined function, but did not, most often due to error condition in the
inlined function.
This change highlights the return branch taken by the inlined function,
in order to help user understand the error report and see why the value
was uninitialized.

rdar://36287652

Differential Revision: https://reviews.llvm.org/D41848

llvm-svn: 325976
2018-02-23 23:26:56 +00:00

227 lines
8.0 KiB
C

// RUN: %clang_analyze_cc1 -x c -analyzer-checker=core -analyzer-output=text -verify %s
typedef __typeof(sizeof(int)) size_t;
void *memset(void *__s, int __c, size_t __n);
int initializer1(int *p, int x) {
if (x) { // expected-note{{Taking false branch}}
*p = 1;
return 0;
} else {
return 1; // expected-note {{Returning without writing to '*p'}}
}
}
int param_not_initialized_by_func() {
int p; // expected-note {{'p' declared without an initial value}}
int out = initializer1(&p, 0); // expected-note{{Calling 'initializer1'}}
// expected-note@-1{{Returning from 'initializer1'}}
return p; // expected-note{{Undefined or garbage value returned to caller}}
// expected-warning@-1{{Undefined or garbage value returned to caller}}
}
int param_initialized_properly() {
int p;
int out = initializer1(&p, 1);
return p; //no-warning
}
static int global;
int initializer2(int **p, int x) {
if (x) { // expected-note{{Taking false branch}}
*p = &global;
return 0;
} else {
return 1; // expected-note {{Returning without writing to '*p'}}
}
}
int param_not_written_into_by_func() {
int *p = 0; // expected-note{{'p' initialized to a null pointer value}}
int out = initializer2(&p, 0); // expected-note{{Calling 'initializer2'}}
// expected-note@-1{{Returning from 'initializer2'}}
return *p; // expected-warning{{Dereference of null pointer (loaded from variable 'p')}}
// expected-note@-1{{Dereference of null pointer (loaded from variable 'p')}}
}
void initializer3(int *p, int param) {
if (param) // expected-note{{Taking false branch}}
*p = 0;
} // expected-note{{Returning without writing to '*p'}}
int param_written_into_by_void_func() {
int p; // expected-note{{'p' declared without an initial value}}
initializer3(&p, 0); // expected-note{{Calling 'initializer3'}}
// expected-note@-1{{Returning from 'initializer3'}}
return p; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
void initializer4(int *p, int param) {
if (param) // expected-note{{Taking false branch}}
*p = 0;
} // expected-note{{Returning without writing to '*p'}}
void initializer5(int *p, int param) {
if (!param) // expected-note{{Taking false branch}}
*p = 0;
} // expected-note{{Returning without writing to '*p'}}
int multi_init_tries_func() {
int p; // expected-note{{'p' declared without an initial value}}
initializer4(&p, 0); // expected-note{{Calling 'initializer4'}}
// expected-note@-1{{Returning from 'initializer4'}}
initializer5(&p, 1); // expected-note{{Calling 'initializer5'}}
// expected-note@-1{{Returning from 'initializer5'}}
return p; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
int initializer6(const int *p) {
return 0;
}
int no_msg_on_const() {
int p; // expected-note{{'p' declared without an initial value}}
initializer6(&p);
return p; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
typedef struct {
int x;
} S;
int initializer7(S *s, int param) {
if (param) { // expected-note{{Taking false branch}}
s->x = 0;
return 0;
}
return 1; // expected-note{{Returning without writing to 's->x'}}
}
int initialize_struct_field() {
S local;
initializer7(&local, 0); // expected-note{{Calling 'initializer7'}}
// expected-note@-1{{Returning from 'initializer7'}}
return local.x; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
void nullwriter(int **p) {
*p = 0; // expected-note{{Null pointer value stored to 'p'}}
} // no extra note
int usage() {
int x = 0;
int *p = &x;
nullwriter(&p); // expected-note{{Calling 'nullwriter'}}
// expected-note@-1{{Returning from 'nullwriter'}}
return *p; // expected-warning{{Dereference of null pointer (loaded from variable 'p')}}
// expected-note@-1{{Dereference of null pointer (loaded from variable 'p')}}
}
typedef struct {
int x;
int y;
} A;
void partial_initializer(A *a) {
a->x = 0;
} // expected-note{{Returning without writing to 'a->y'}}
int use_partial_initializer() {
A a;
partial_initializer(&a); // expected-note{{Calling 'partial_initializer'}}
// expected-note@-1{{Returning from 'partial_initializer'}}
return a.y; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
typedef struct {
int x;
int y;
} B;
typedef struct {
B b;
} C;
void partial_nested_initializer(C *c) {
c->b.x = 0;
} // expected-note{{Returning without writing to 'c->b.y'}}
int use_partial_nested_initializer() {
B localB;
C localC;
localC.b = localB;
partial_nested_initializer(&localC); // expected-note{{Calling 'partial_nested_initializer'}}
// expected-note@-1{{Returning from 'partial_nested_initializer'}}
return localC.b.y; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
void test_subregion_assignment(C* c) {
B b;
c->b = b;
}
int use_subregion_assignment() {
C c;
test_subregion_assignment(&c); // expected-note{{Calling 'test_subregion_assignment'}}
// expected-note@-1{{Returning from 'test_subregion_assignment'}}
return c.b.x; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}
int confusing_signature(int *);
int confusing_signature(int *p) {
return 0; // expected-note{{Returning without writing to '*p'}}
}
int use_confusing_signature() {
int a; // expected-note {{'a' declared without an initial value}}
confusing_signature(&a); // expected-note{{Calling 'confusing_signature'}}
// expected-note@-1{{Returning from 'confusing_signature'}}
return a; // expected-note{{Undefined or garbage value returned to caller}}
// expected-warning@-1{{Undefined or garbage value returned to caller}}
}
int coin();
int multiindirection(int **p) {
if (coin()) // expected-note{{Assuming the condition is true}}
// expected-note@-1{{Taking true branch}}
return 1; // expected-note{{Returning without writing to '**p'}}
*(*p) = 0;
return 0;
}
int usemultiindirection() {
int a; // expected-note {{'a' declared without an initial value}}
int *b = &a;
multiindirection(&b); // expected-note{{Calling 'multiindirection'}}
// expected-note@-1{{Returning from 'multiindirection'}}
return a; // expected-note{{Undefined or garbage value returned to caller}}
// expected-warning@-1{{Undefined or garbage value returned to caller}}
}
int indirectingstruct(S** s) {
if (coin()) // expected-note{{Assuming the condition is true}}
// expected-note@-1{{Taking true branch}}
return 1; // expected-note{{Returning without writing to '(*s)->x'}}
(*s)->x = 0;
return 0;
}
int useindirectingstruct() {
S s;
S* p = &s;
indirectingstruct(&p); //expected-note{{Calling 'indirectingstruct'}}
//expected-note@-1{{Returning from 'indirectingstruct'}}
return s.x; // expected-warning{{Undefined or garbage value returned to caller}}
// expected-note@-1{{Undefined or garbage value returned to caller}}
}