clang/test/Sema/nonnull.c

   1 // RUN: %clang_cc1 -fsyntax-only -verify -Wno-strict-prototypes %s
   2 //
   3 // Verify All warnings are still issued with the option -fno-delete-null-pointer-checks
   4 // if nullptr is passed to function with nonnull attribute.
   5 // RUN: %clang_cc1 -fsyntax-only -fno-delete-null-pointer-checks -verify %s
   6
   7 typedef struct {
   8         char *str;
   9 } Class;
  10
  11 typedef union {
  12         Class *object;
  13 } Instance __attribute__((transparent_union));
  14
  15 __attribute__((nonnull(1))) void Class_init(Instance this, char *str) {
  16         this.object->str = str;
  17 }
  18
  19 int main(void) {
  20         Class *obj;
  21         Class_init(0, "Hello World"); // expected-warning {{null passed to a callee that requires a non-null argument}}
  22         Class_init(obj, "Hello World");
  23 }
  24
  25 void foo(const char *str) __attribute__((nonnull("foo"))); // expected-error{{'nonnull' attribute requires parameter 1 to be an integer constant}}
  26 void bar(int i) __attribute__((nonnull(1))); // expected-warning {{'nonnull' attribute only applies to pointer arguments}} expected-warning {{'nonnull' attribute applied to function with no pointer arguments}}
  27
  28 void baz(__attribute__((nonnull)) const char *str);
  29 void baz2(__attribute__((nonnull(1))) const char *str); // expected-warning {{'nonnull' attribute when used on parameters takes no arguments}}
  30 void baz3(__attribute__((nonnull)) int x); // expected-warning {{'nonnull' attribute only applies to pointer arguments}}
  31
  32 void test_baz(void) {
  33   baz(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
  34   baz2(0); // no-warning
  35   baz3(0); // no-warning
  36 }
  37
  38 void test_void_returns_nonnull(void) __attribute__((returns_nonnull)); // expected-warning {{'returns_nonnull' attribute only applies to return values that are pointers}}
  39 int test_int_returns_nonnull(void) __attribute__((returns_nonnull)); // expected-warning {{'returns_nonnull' attribute only applies to return values that are pointers}}
  40 void *test_ptr_returns_nonnull(void) __attribute__((returns_nonnull)); // no-warning
  41
  42 int i __attribute__((nonnull)); // expected-warning {{'nonnull' attribute only applies to functions, methods, and parameters}}
  43 int j __attribute__((returns_nonnull)); // expected-warning {{'returns_nonnull' attribute only applies to Objective-C methods and functions}}
  44 void *test_no_fn_proto() __attribute__((returns_nonnull)); // no-warning
  45 void *test_with_fn_proto(void) __attribute__((returns_nonnull)); // no-warning
  46
  47 __attribute__((returns_nonnull))
  48 void *test_bad_returns_null(void) {
  49   return 0; // expected-warning {{null returned from function that requires a non-null return value}}
  50 }
  51
  52 void PR18795(int (*g)(const char *h, ...) __attribute__((nonnull(1))) __attribute__((nonnull))) {
  53   g(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
  54 }
  55 void PR18795_helper(void) {
  56   PR18795(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
  57 }
  58
  59 void vararg1(int n, ...) __attribute__((nonnull(2)));
  60 void vararg1_test(void) {
  61   vararg1(0);
  62   vararg1(1, (void*)0); // expected-warning{{null passed}}
  63   vararg1(2, (void*)0, (void*)0); // expected-warning{{null passed}}
  64   vararg1(2, (void*)&vararg1, (void*)0);
  65 }
  66
  67 void vararg2(int n, ...) __attribute__((nonnull, nonnull, nonnull));
  68 void vararg2_test(void) {
  69   vararg2(0);
  70   vararg2(1, (void*)0); // expected-warning{{null passed}}
  71   vararg2(2, (void*)0, (void*)0); // expected-warning 2{{null passed}}
  72 }
  73
  74 void vararg3(int n, ...) __attribute__((nonnull, nonnull(2), nonnull(3)));
  75 void vararg3_test(void) {
  76   vararg3(0);
  77   vararg3(1, (void*)0); // expected-warning{{null passed}}
  78   vararg3(2, (void*)0, (void*)0); // expected-warning 2{{null passed}}
  79 }
  80
  81 void redecl(void *, void *);
  82 void redecl(void *, void *) __attribute__((nonnull(1)));
  83 void redecl(void *, void *) __attribute__((nonnull(2)));
  84 void redecl(void *, void *);
  85 void redecl_test(void *p) {
  86   redecl(p, 0); // expected-warning{{null passed}}
  87   redecl(0, p); // expected-warning{{null passed}}
  88 }
  89
  90 #define NULL (void*)0
  91 __attribute__((__nonnull__))  // expected-note 2{{declared 'nonnull' here}}
  92 int evil_nonnull_func(int* pointer, void * pv)
  93 {
  94    if (pointer == NULL) {  // expected-warning {{comparison of nonnull parameter 'pointer' equal to a null pointer is 'false' on first encounter}}
  95      return 0;
  96    } else {
  97      return *pointer;
  98    }
  99
 100    pointer = pv;
 101    if (!pointer)
 102      return 0;
 103    else
 104      return *pointer;
 105
 106    if (pv == NULL) {} // expected-warning {{comparison of nonnull parameter 'pv' equal to a null pointer is 'false' on first encounter}}
 107 }
 108
 109 void set_param_to_null(int**);
 110 int another_evil_nonnull_func(int* pointer, char ch, void * pv) __attribute__((nonnull(1, 3)));  // expected-note 2{{declared 'nonnull' here}}
 111 int another_evil_nonnull_func(int* pointer, char ch, void * pv) {
 112    if (pointer == NULL) { // expected-warning {{comparison of nonnull parameter 'pointer' equal to a null pointer is 'false' on first encounter}}
 113      return 0;
 114    } else {
 115      return *pointer;
 116    }
 117
 118    set_param_to_null(&pointer);
 119    if (!pointer)
 120      return 0;
 121    else
 122      return *pointer;
 123
 124    if (pv == NULL) {} // expected-warning {{comparison of nonnull parameter 'pv' equal to a null pointer is 'false' on first encounter}}
 125 }
 126
 127 extern void *returns_null(void**);
 128 extern void FOO(void);
 129 extern void FEE(void);
 130
 131 extern void *pv;
 132 __attribute__((__nonnull__))  // expected-note {{declared 'nonnull' here}}
 133 void yet_another_evil_nonnull_func(int* pointer)
 134 {
 135  while (pv) {
 136    // This comparison will not be optimized away.
 137    if (pointer) {  // expected-warning {{nonnull parameter 'pointer' will evaluate to 'true' on first encounter}}
 138      FOO();
 139    } else {
 140      FEE();
 141    }
 142    pointer = returns_null(&pv);
 143  }
 144 }
 145
 146 void pr21668_1(__attribute__((nonnull)) const char *p, const char *s) { // expected-note {{declared 'nonnull' here}}
 147   if (p) // expected-warning {{nonnull parameter 'p' will evaluate to 'true' on first encounter}}
 148     ;
 149   if (s) // No warning
 150     ;
 151 }
 152
 153 void pr21668_2(__attribute__((nonnull)) const char *p) {
 154   p = 0;
 155   if (p) // No warning
 156     ;
 157 }
 158
 159 __attribute__((returns_nonnull)) void *returns_nonnull_whee(void);  // expected-note 6{{declared 'returns_nonnull' here}}
 160
 161 void returns_nonnull_warning_tests() {
 162   if (returns_nonnull_whee() == NULL) {} // expected-warning {{comparison of nonnull function call 'returns_nonnull_whee()' equal to a null pointer is 'false' on first encounter}}
 163
 164   if (returns_nonnull_whee() != NULL) {} // expected-warning {{comparison of nonnull function call 'returns_nonnull_whee()' not equal to a null pointer is 'true' on first encounter}}
 165
 166   if (returns_nonnull_whee()) {} // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 167   if (!returns_nonnull_whee()) {} // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 168
 169   int and_again = !returns_nonnull_whee(); // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 170   and_again = !returns_nonnull_whee(); // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 171 }
 172
 173 void pr30828(char *p __attribute__((nonnull)));
 174 void pr30828(char *p) {}
 175
 176 void call_pr30828(void) {
 177   pr30828(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
 178 }