gcc/testsuite/gcc.dg/Wreturn-local-addr-3.c

   1 /* PR c/71924 - missing -Wreturn-local-addr returning alloca result
   2    { dg-do compile }
   3    { dg-options "-O2 -Wall" }
   4    { dg-require-effective-target alloca } */
   5
   6 #define ATTR(...) __attribute__ ((__VA_ARGS__))
   7
   8 typedef __INTPTR_TYPE__ intptr_t;
   9
  10 struct A { int a, b, c; };
  11 struct B { int a, b, c[]; };
  12
  13 extern int g1[5], g2[5], g3[5], g4[5], g5[5];
  14
  15 void sink (void*, ...);
  16
  17 /* Verify that a pointer difference expression is handled correctly
  18    even when converted to a pointer.  */
  19
  20 ATTR (noipa) void*
  21 return_local_diff_cst (void)
  22 {
  23   int a[5];
  24   void *p = (void*)(&a[4] - &a[1]);
  25   return p;
  26 }
  27
  28 ATTR (noipa) void*
  29 return_local_diff_var (int i, int j)
  30 {
  31   int a[5];
  32   void *p = (void*)(&a[j] - &a[i]);
  33   return p;
  34 }
  35
  36 ATTR (noipa) void*
  37 return_2_locals (int i)
  38 {
  39   int a[1];         /* { dg-message "declared here" } */
  40   int b[2];         /* { dg-message "declared here" } */
  41   void *p = i < 0 ? a : b;
  42   return p;         /* { dg-warning "function returns address of local" } */
  43 }
  44
  45 /* Verify that returning the address of a local converted to intptr_t
  46    is not diagnosed (see bug 90737 for a case the front-end gets wrong).  */
  47
  48 ATTR (noipa) intptr_t
  49 return_int_2_locals (int i)
  50 {
  51   int a[1];
  52   int b[2];
  53   void *p = i < 0 ? a : b;
  54   return (intptr_t)p;
  55 }
  56
  57 /* Verify that a conditional expression with a pointer first operand
  58    is handled correctly.  */
  59
  60 ATTR (noipa) void*
  61 return_2_locals_ptrcond (void *q)
  62 {
  63   int a[1];         /* { dg-message "declared here" } */
  64   int b[2];         /* { dg-message "declared here" } */
  65   void *p = q ? a : b;
  66   return p;         /* { dg-warning "function returns address of local" } */
  67 }
  68
  69 /* Verify that a preincrement expression with a pointer operand is
  70    handled correctly.  */
  71
  72 ATTR (noipa) void*
  73 return_2_locals_ptrinc (void *q)
  74 {
  75   int a[1];         /* { dg-message "declared here" } */
  76   int b[2];         /* { dg-message "declared here" } */
  77   int *p = q ? a : b;
  78   return ++p;       /* { dg-warning "function returns address of local" } */
  79 }
  80
  81 ATTR (noipa) void*
  82 return_3_locals (int i)
  83 {
  84   int a[1];         /* { dg-message "declared here" } */
  85   int b[2];         /* { dg-message "declared here" } */
  86   int c[3];         /* { dg-message "declared here" } */
  87
  88   void *p = i < 0 ? a : 0 < i ? c : b;
  89   return p;         /* { dg-warning "function returns address of local" } */
  90 }
  91
  92 /* Verify that a conditional expression with a pointer first operand
  93    is handled correctly.  */
  94
  95 ATTR (noipa) void*
  96 return_3_locals_ptrcond (void *p, void *q)
  97 {
  98   int a[1];         /* { dg-message "declared here" } */
  99   int b[2];         /* { dg-message "declared here" } */
 100   int c[3];         /* { dg-message "declared here" } */
 101
 102   void *r = q ? r ? a : b : c;
 103   return r;         /* { dg-warning "function returns address of local" } */
 104 }
 105
 106 ATTR (noipa) void*
 107 return_5_locals (int i)
 108 {
 109   int a[1];         /* { dg-message "declared here" } */
 110   int b[2];         /* { dg-message "declared here" } */
 111   int c[3];         /* { dg-message "declared here" } */
 112   int d[4];         /* { dg-message "declared here" } */
 113   int e[5];         /* { dg-message "declared here" } */
 114
 115   void *p = i < -1 ? a : i < 0 ? b : 1 < i ? e : 0 < i ? d : c;
 116   return p;         /* { dg-warning "function returns address of local" } */
 117 }
 118
 119 ATTR (noipa) void*
 120 return_1_global_4_locals (int i)
 121 {
 122   int a[1];         /* { dg-message "declared here" } */
 123   int b[2];         /* { dg-message "declared here" } */
 124   int c[3];         /* { dg-message "declared here" } */
 125   int d[4];         /* { dg-message "declared here" } */
 126
 127   void *p = i < -1 ? a : i < 0 ? b : 1 < i ? g1 : 0 < i ? d : c;
 128   return p;         /* { dg-warning "function may return address of local" } */
 129 }
 130
 131 ATTR (noipa) void*
 132 return_2_globals_3_locals (int i)
 133 {
 134   int a[1];         /* { dg-message "declared here" } */
 135   int b[2];         /* { dg-message "declared here" } */
 136   int c[3];         /* { dg-message "declared here" } */
 137
 138   void *p = i < -1 ? a : i < 0 ? b : 1 < i ? g1 : 0 < i ? g2 : c;
 139   return p;         /* { dg-warning "function may return address of local" } */
 140 }
 141
 142 ATTR (noipa) void*
 143 return_3_globals_2_locals (int i)
 144 {
 145   int a[1];         /* { dg-message "declared here" } */
 146   int b[2];         /* { dg-message "declared here" } */
 147
 148   void *p = i < -1 ? a : i < 0 ? b : 1 < i ? g1 : 0 < i ? g2 : g3;
 149   return p;         /* { dg-warning "function may return address of local" } */
 150 }
 151
 152 ATTR (noipa) void*
 153 return_4_globals_1_local (int i)
 154 {
 155   int a[1];         /* { dg-message "declared here" } */
 156
 157   void *p = i < -1 ? a : i < 0 ? g1 : 1 < i ? g2 : 0 < i ? g4 : g3;
 158   return p;         /* { dg-warning "function may return address of local" } */
 159 }
 160
 161 ATTR (noipa) void*
 162 return_all_globals (int i)
 163 {
 164   void *p = i < -1 ? g1 : i < 0 ? g2 : 1 < i ? g3 : 0 < i ? g5 : g4;
 165   return p;
 166 }
 167
 168
 169 ATTR (noipa) void*
 170 return_2_alloca_local_cstoff (int n, int i)
 171 {
 172   int *a = __builtin_alloca (n);  /* { dg-message "declared here" } */
 173   int *b = __builtin_alloca (n);  /* { dg-message "declared here" } */
 174   int *p = i < 0 ? a : b;
 175   p += 1;
 176   sink (p);
 177   return p;         /* { dg-warning "function returns address of local" } */
 178 }
 179
 180 ATTR (noipa) void*
 181 return_alloca_local_cstoff (int n, int i)
 182 {
 183   int *a = __builtin_alloca (n);  /* { dg-message "declared here" } */
 184   int b[2];                       /* { dg-message "declared here" } */
 185   int *p = i < 0 ? a : b;
 186   p += 1;
 187   sink (p);
 188   return p;         /* { dg-warning "function returns address of local" } */
 189 }
 190
 191 ATTR (noipa) void*
 192 return_local_alloca_cstoff (int n, int i)
 193 {
 194   int a[2];                       /* { dg-message "declared here" } */
 195   int *b = __builtin_alloca (n);  /* { dg-message "declared here" } */
 196   int *p = i < 0 ? a : b;
 197   p += 1;
 198   sink (p);
 199   return p;         /* { dg-warning "function returns address of local" } */
 200 }
 201
 202 ATTR (noipa) void*
 203 return_2_locals_cstoff (int i)
 204 {
 205   int a[1];         /* { dg-message "declared here" } */
 206   int b[2];         /* { dg-message "declared here" } */
 207   int *p = i < 0 ? a : b;
 208   p += 1;
 209   sink (p);
 210   return p;         /* { dg-warning "function returns address of local" } */
 211 }
 212
 213 ATTR (noipa) void*
 214 return_2_globals_3_locals_cstoff (int i)
 215 {
 216   int a[1];         /* { dg-message "declared here" } */
 217   int b[2];         /* { dg-message "declared here" } */
 218   int c[3];         /* { dg-message "declared here" } */
 219
 220   int *p = i < -1 ? a : i < 0 ? b : 1 < i ? g1 : 0 < i ? g2 : c;
 221   p += 1;
 222   sink (p);
 223   return p;         /* { dg-warning "function may return address of local" } */
 224 }
 225
 226 ATTR (noipa) void*
 227 return_3_globals_alloca_local_varoff (int n, int i, int j)
 228 {
 229   int *a = __builtin_alloca (n);  /* { dg-message "declared here" } */
 230   int b[2];                       /* { dg-message "declared here" } */
 231
 232   int *p = i < -1 ? a : i < 0 ? b : 1 < i ? g1 : 0 < i ? g2 : g3;
 233   p += j;
 234   sink (p);
 235   return p;         /* { dg-warning "function may return address of local" } */
 236 }
 237
 238 ATTR (noipa) void*
 239 return_3_globals_2_locals_varoff (int i, int j)
 240 {
 241   int a[1];         /* { dg-message "declared here" } */
 242   int b[2];         /* { dg-message "declared here" } */
 243
 244   int *p = i < -1 ? a : i < 0 ? b : 1 < i ? g1 : 0 < i ? g2 : g3;
 245   p += j;
 246   sink (p);
 247   return p;         /* { dg-warning "function may return address of local" } */
 248 }
 249