clang/test/Sema/nonnull.c

   1 // RUN: %clang_cc1 -fsyntax-only -verify -Wno-strict-prototypes %s
   2 // rdar://9584012
   3 //
   4 // Verify All warnings are still issued with the option -fno-delete-null-pointer-checks
   5 // if nullptr is passed to function with nonnull attribute.
   6 // RUN: %clang_cc1 -fsyntax-only -fno-delete-null-pointer-checks -verify %s
   7
   8 typedef struct {
   9         char *str;
  10 } Class;
  11
  12 typedef union {
  13         Class *object;
  14 } Instance __attribute__((transparent_union));
  15
  16 __attribute__((nonnull(1))) void Class_init(Instance this, char *str) {
  17         this.object->str = str;
  18 }
  19
  20 int main(void) {
  21         Class *obj;
  22         Class_init(0, "Hello World"); // expected-warning {{null passed to a callee that requires a non-null argument}}
  23         Class_init(obj, "Hello World");
  24 }
  25
  26 void foo(const char *str) __attribute__((nonnull("foo"))); // expected-error{{'nonnull' attribute requires parameter 1 to be an integer constant}}
  27 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}}
  28
  29 void baz(__attribute__((nonnull)) const char *str);
  30 void baz2(__attribute__((nonnull(1))) const char *str); // expected-warning {{'nonnull' attribute when used on parameters takes no arguments}}
  31 void baz3(__attribute__((nonnull)) int x); // expected-warning {{'nonnull' attribute only applies to pointer arguments}}
  32
  33 void test_baz(void) {
  34   baz(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
  35   baz2(0); // no-warning
  36   baz3(0); // no-warning
  37 }
  38
  39 void test_void_returns_nonnull(void) __attribute__((returns_nonnull)); // expected-warning {{'returns_nonnull' attribute only applies to return values that are pointers}}
  40 int test_int_returns_nonnull(void) __attribute__((returns_nonnull)); // expected-warning {{'returns_nonnull' attribute only applies to return values that are pointers}}
  41 void *test_ptr_returns_nonnull(void) __attribute__((returns_nonnull)); // no-warning
  42
  43 int i __attribute__((nonnull)); // expected-warning {{'nonnull' attribute only applies to functions, methods, and parameters}}
  44 int j __attribute__((returns_nonnull)); // expected-warning {{'returns_nonnull' attribute only applies to Objective-C methods and functions}}
  45 void *test_no_fn_proto() __attribute__((returns_nonnull)); // no-warning
  46 void *test_with_fn_proto(void) __attribute__((returns_nonnull)); // no-warning
  47
  48 __attribute__((returns_nonnull))
  49 void *test_bad_returns_null(void) {
  50   return 0; // expected-warning {{null returned from function that requires a non-null return value}}
  51 }
  52
  53 void PR18795(int (*g)(const char *h, ...) __attribute__((nonnull(1))) __attribute__((nonnull))) {
  54   g(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
  55 }
  56 void PR18795_helper(void) {
  57   PR18795(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
  58 }
  59
  60 void vararg1(int n, ...) __attribute__((nonnull(2)));
  61 void vararg1_test(void) {
  62   vararg1(0);
  63   vararg1(1, (void*)0); // expected-warning{{null passed}}
  64   vararg1(2, (void*)0, (void*)0); // expected-warning{{null passed}}
  65   vararg1(2, (void*)&vararg1, (void*)0);
  66 }
  67
  68 void vararg2(int n, ...) __attribute__((nonnull, nonnull, nonnull));
  69 void vararg2_test(void) {
  70   vararg2(0);
  71   vararg2(1, (void*)0); // expected-warning{{null passed}}
  72   vararg2(2, (void*)0, (void*)0); // expected-warning 2{{null passed}}
  73 }
  74
  75 void vararg3(int n, ...) __attribute__((nonnull, nonnull(2), nonnull(3)));
  76 void vararg3_test(void) {
  77   vararg3(0);
  78   vararg3(1, (void*)0); // expected-warning{{null passed}}
  79   vararg3(2, (void*)0, (void*)0); // expected-warning 2{{null passed}}
  80 }
  81
  82 void redecl(void *, void *);
  83 void redecl(void *, void *) __attribute__((nonnull(1)));
  84 void redecl(void *, void *) __attribute__((nonnull(2)));
  85 void redecl(void *, void *);
  86 void redecl_test(void *p) {
  87   redecl(p, 0); // expected-warning{{null passed}}
  88   redecl(0, p); // expected-warning{{null passed}}
  89 }
  90
  91 // rdar://18712242
  92 #define NULL (void*)0
  93 __attribute__((__nonnull__))  // expected-note 2{{declared 'nonnull' here}}
  94 int evil_nonnull_func(int* pointer, void * pv)
  95 {
  96    if (pointer == NULL) {  // expected-warning {{comparison of nonnull parameter 'pointer' equal to a null pointer is 'false' on first encounter}}
  97      return 0;
  98    } else {
  99      return *pointer;
 100    }
 101
 102    pointer = pv;
 103    if (!pointer)
 104      return 0;
 105    else
 106      return *pointer;
 107
 108    if (pv == NULL) {} // expected-warning {{comparison of nonnull parameter 'pv' equal to a null pointer is 'false' on first encounter}}
 109 }
 110
 111 void set_param_to_null(int**);
 112 int another_evil_nonnull_func(int* pointer, char ch, void * pv) __attribute__((nonnull(1, 3)));  // expected-note 2{{declared 'nonnull' here}}
 113 int another_evil_nonnull_func(int* pointer, char ch, void * pv) {
 114    if (pointer == NULL) { // expected-warning {{comparison of nonnull parameter 'pointer' equal to a null pointer is 'false' on first encounter}}
 115      return 0;
 116    } else {
 117      return *pointer;
 118    }
 119
 120    set_param_to_null(&pointer);
 121    if (!pointer)
 122      return 0;
 123    else
 124      return *pointer;
 125
 126    if (pv == NULL) {} // expected-warning {{comparison of nonnull parameter 'pv' equal to a null pointer is 'false' on first encounter}}
 127 }
 128
 129 extern void *returns_null(void**);
 130 extern void FOO(void);
 131 extern void FEE(void);
 132
 133 extern void *pv;
 134 __attribute__((__nonnull__))  // expected-note {{declared 'nonnull' here}}
 135 void yet_another_evil_nonnull_func(int* pointer)
 136 {
 137  while (pv) {
 138    // This comparison will not be optimized away.
 139    if (pointer) {  // expected-warning {{nonnull parameter 'pointer' will evaluate to 'true' on first encounter}}
 140      FOO();
 141    } else {
 142      FEE();
 143    }
 144    pointer = returns_null(&pv);
 145  }
 146 }
 147
 148 void pr21668_1(__attribute__((nonnull)) const char *p, const char *s) { // expected-note {{declared 'nonnull' here}}
 149   if (p) // expected-warning {{nonnull parameter 'p' will evaluate to 'true' on first encounter}}
 150     ;
 151   if (s) // No warning
 152     ;
 153 }
 154
 155 void pr21668_2(__attribute__((nonnull)) const char *p) {
 156   p = 0;
 157   if (p) // No warning
 158     ;
 159 }
 160
 161 __attribute__((returns_nonnull)) void *returns_nonnull_whee(void);  // expected-note 6{{declared 'returns_nonnull' here}}
 162
 163 void returns_nonnull_warning_tests() {
 164   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}}
 165
 166   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}}
 167
 168   if (returns_nonnull_whee()) {} // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 169   if (!returns_nonnull_whee()) {} // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 170
 171   int and_again = !returns_nonnull_whee(); // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 172   and_again = !returns_nonnull_whee(); // expected-warning {{nonnull function call 'returns_nonnull_whee()' will evaluate to 'true' on first encounter}}
 173 }
 174
 175 void pr30828(char *p __attribute__((nonnull)));
 176 void pr30828(char *p) {}
 177
 178 void call_pr30828(void) {
 179   pr30828(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
 180 }