gcc/testsuite/gcc.dg/Wstringop-overflow-75.c

   1 /* Verify warnings and notes for MIN_EXPRs involving either pointers
   2    to distinct objects or one to a known object and the other to
   3    an unknown one.  The relational expressions are strictly invalid
   4    but that should be diagnosed by a separate warning.
   5    { dg-do compile }
   6    { dg-options "-O2 -Wno-array-bounds" } */
   7
   8 /* Verify the note points to the larger of the two objects and mentions
   9    the offset into it (although the offset might be better included in
  10    the warning).  */
  11 extern char a3[3];
  12 extern char a5[5];  // { dg-message "at offset \[^a-zA-Z\n\r\]*5\[^a-zA-Z0-9\]* into destination object 'a5' of size 5" "note" }
  13
  14 void min_a3_a5 (int i)
  15 {
  16   char *p = a3 + i;
  17   char *q = a5 + i;
  18
  19   /* The relational expression below is invalid and should be diagnosed
  20      by its own warning independently of -Wstringop-overflow.  */
  21   char *d = p < q ? p : q;
  22
  23   d[4] = 0;         // { dg-warning "writing 2 bytes into a region of size 1" "" { target { vect_slp_v2qi_store_unalign } } }
  24   d[5] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
  25 }
  26
  27
  28 // Same as above but with the larger array as the first MIN_EXPR operand.
  29 extern char b4[4];
  30 extern char b6[6];  // { dg-message "at offset \[^a-zA-Z\n\r\]*6\[^a-zA-Z0-9\]* into destination object 'b6' of size 6" "note" }
  31
  32 void min_b6_b4 (int i)
  33 {
  34   char *p = b6 + i;
  35   char *q = b4 + i;
  36   char *d = p < q ? p : q;
  37
  38   d[5] = 0;         // { dg-warning "writing 2 bytes into a region of size 1" "" { target { vect_slp_v2qi_store_unalign } } }
  39   d[6] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
  40 }
  41
  42
  43 /* Same as above but with the first MIN_EXPR operand pointing to an unknown
  44    object.  */
  45 extern char c7[7];  // { dg-message "at offset 7 into destination object 'c7' of size 7" "note" { xfail { vect_slp_v2qi_store_unalign } } }
  46
  47 void min_p_c7 (char *p, int i)
  48 {
  49   char *q = c7 + i;
  50   char *d = p < q ? p : q;
  51
  52   d[6] = 0;         // { dg-warning "writing 2 bytes into a region of size 1" "" { target { vect_slp_v2qi_store_unalign } } }
  53   d[7] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
  54 }
  55
  56
  57 /* Same as above but with the second MIN_EXPR operand pointing to an unknown
  58    object.  */
  59 extern char d8[8];  // { dg-message "at offset 8 into destination object 'd8' of size 8" "note" { xfail { vect_slp_v2qi_store_unalign } } }
  60
  61 void min_d8_p (char *q, int i)
  62 {
  63   char *p = d8 + i;
  64   char *d = p < q ? p : q;
  65
  66   d[7] = 0;         // { dg-warning "writing 2 bytes into a region of size 1" "" { target { vect_slp_v2qi_store_unalign } } }
  67   d[8] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
  68 }
  69
  70
  71 struct A3_5
  72 {
  73   char a3[3];
  74   char a5[5];  // { dg-message "at offset 5 into destination object 'a5' of size 5" "note" }
  75 };
  76
  77 void min_A3_A5 (int i, struct A3_5 *pa3_5)
  78 {
  79   char *p = pa3_5->a3 + i;
  80   char *q = pa3_5->a5 + i;
  81
  82   char *d = p < q ? p : q;
  83
  84   // d[4] = 0;
  85   d[5] = 0;         // { dg-warning "writing 1 byte into a region of size 0" }
  86 }
  87
  88
  89 struct B4_B6
  90 {
  91   char b4[4];
  92   char b6[6];       // { dg-message "at offset 6 into destination object 'b6' of size 6" "note" { xfail { vect_slp_v2qi_store_unalign } } }
  93 };
  94
  95 void min_B6_B4 (int i, struct B4_B6 *pb4_b6)
  96 {
  97   char *p = pb4_b6->b6 + i;
  98   char *q = pb4_b6->b4 + i;
  99   char *d = p < q ? p : q;
 100
 101   d[5] = 0;
 102   d[6] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
 103 }
 104
 105
 106 struct C7
 107 {
 108   char c7[7];       // { dg-message "at offset 7 into destination object 'c7' of size 7" "note" { xfail { vect_slp_v2qi_store_unalign } } }
 109 };
 110
 111 void min_p_C7 (char *p, int i, struct C7 *pc7)
 112 {
 113   char *q = pc7->c7 + i;
 114   char *d = p < q ? p : q;
 115
 116   d[6] = 0;
 117   d[7] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
 118 }
 119
 120
 121 struct D8
 122 {
 123   char d8[8];       // { dg-message "at offset 8 into destination object 'd8' of size 8" "note" { xfail { vect_slp_v2qi_store_unalign } } }
 124 };
 125
 126 void min_D8_p (char *q, int i, struct D8 *pd8)
 127 {
 128   char *p = pd8->d8 + i;
 129   char *d = p < q ? p : q;
 130
 131   d[7] = 0;
 132   d[8] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
 133 }