xref: /llvm-project/clang/test/Analysis/builtin_overflow_notes.c (revision a017ed04cc9bcc75b3c3ef35c923dbe7dc4606f8)
1*a017ed04SPavel Skripkin // RUN: %clang_analyze_cc1 -analyzer-checker=core -analyzer-output text \
2*a017ed04SPavel Skripkin // RUN:   -verify %s
3*a017ed04SPavel Skripkin 
4*a017ed04SPavel Skripkin void test_no_overflow_note(int a, int b)
5*a017ed04SPavel Skripkin {
6*a017ed04SPavel Skripkin    int res;
7*a017ed04SPavel Skripkin 
8*a017ed04SPavel Skripkin    if (__builtin_add_overflow(a, b, &res)) // expected-note {{Assuming no overflow}}
9*a017ed04SPavel Skripkin                                            // expected-note@-1 {{Taking false branch}}
10*a017ed04SPavel Skripkin      return;
11*a017ed04SPavel Skripkin 
12*a017ed04SPavel Skripkin    if (res) { // expected-note {{Assuming 'res' is not equal to 0}}
13*a017ed04SPavel Skripkin               // expected-note@-1 {{Taking true branch}}
14*a017ed04SPavel Skripkin      int *ptr = 0; // expected-note {{'ptr' initialized to a null pointer value}}
15*a017ed04SPavel Skripkin      int var = *(int *) ptr; //expected-warning {{Dereference of null pointer}}
16*a017ed04SPavel Skripkin                              //expected-note@-1 {{Dereference of null pointer}}
17*a017ed04SPavel Skripkin    }
18*a017ed04SPavel Skripkin }
19*a017ed04SPavel Skripkin 
20*a017ed04SPavel Skripkin void test_overflow_note(int a, int b)
21*a017ed04SPavel Skripkin {
22*a017ed04SPavel Skripkin    int res; // expected-note{{'res' declared without an initial value}}
23*a017ed04SPavel Skripkin 
24*a017ed04SPavel Skripkin    if (__builtin_add_overflow(a, b, &res)) { // expected-note {{Assuming overflow}}
25*a017ed04SPavel Skripkin                                              // expected-note@-1 {{Taking true branch}}
26*a017ed04SPavel Skripkin      int var = res; // expected-warning{{Assigned value is garbage or undefined}}
27*a017ed04SPavel Skripkin                     // expected-note@-1 {{Assigned value is garbage or undefined}}
28*a017ed04SPavel Skripkin      return;
29*a017ed04SPavel Skripkin    }
30*a017ed04SPavel Skripkin }
31