gcc/testsuite/gcc.dg/Wstringop-overflow-76.c

   1 /* Verify warnings and notes for MAX_EXPRs involving either pointers
   2    to distinct objects or one to a known object and the other to
   3    an unknown one.  Unlike for the same object, for unrelated objects
   4    the expected warnings and notes are the same as for MIN_EXPR: when
   5    the order of the objects in the address space cannot be determined
   6    the larger of them is assumed to be used.  (This is different for
   7    distinct struct members where the order is given.)
   8    The relational expressions are strictly invalid but that should be
   9    diagnosed by a separate warning.
  10    { dg-do compile }
  11    { dg-options "-O2 -Wno-array-bounds" } */
  12
  13 #define MAX(p, q) ((p) > (q) ? (p) : (q))
  14
  15 /* Verify that even for MAX_EXPR and like for MIN_EXPR, the note points
  16    to the larger of the two objects and mentions the offset into it
  17    (although the offset might be better included in the warning).  */
  18 extern char a3[3];
  19 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" }
  20
  21 void max_a3_a5 (int i)
  22 {
  23   char *p = a3 + i;
  24   char *q = a5 + i;
  25
  26   /* The relational expression below is invalid and should be diagnosed
  27      by its own warning independently of -Wstringop-overflow.  */
  28   char *d = MAX (p, q);
  29
  30   d[2] = 0;         // { dg-warning "writing 4 bytes into a region of size 3" "pr102706" { target { vect_slp_v4qi_store_unalign } } }
  31   d[3] = 0;
  32   d[4] = 0;
  33   d[5] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "pr102706" { xfail { vect_slp_v4qi_store_unalign } } }
  34 }
  35
  36
  37 // Same as above but with the larger array as the first MAX_EXPR operand.
  38 extern char b4[4];
  39 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" }
  40
  41 void max_b6_b4 (int i)
  42 {
  43   char *p = b6 + i;
  44   char *q = b4 + i;
  45   char *d = MAX (p, q);
  46
  47   d[3] = 0;         // { dg-warning "writing 4 bytes into a region of size 3" "pr102706" { target { vect_slp_v4qi_store_unalign } } }
  48   d[4] = 0;
  49   d[5] = 0;
  50   d[6] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "pr102706" { xfail { vect_slp_v4qi_store_unalign } } }
  51 }
  52
  53
  54 /* Same as above but with the first MAX_EXPR operand pointing to an unknown
  55    object.  */
  56 extern char c7[7];  // { dg-message "at offset 7 into destination object 'c7' of size 7" "note"  { xfail { vect_slp_v2qi_store_unalign } } }
  57
  58 void max_p_c7 (char *p, int i)
  59 {
  60   char *q = c7 + i;
  61   char *d = MAX (p, q);
  62
  63   d[6] = 0;         // { dg-warning "writing 2 bytes into a region of size 1" "" { target { vect_slp_v2qi_store_unalign } } }
  64   d[7] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
  65 }
  66
  67
  68 /* Same as above but with the second MIN_EXPR operand pointing to an unknown
  69    object.  */
  70 extern char d8[8];  // { dg-message "at offset 8 into destination object 'd8' of size 8" "note"  { xfail { vect_slp_v2qi_store_unalign } } }
  71
  72 void max_d8_p (char *q, int i)
  73 {
  74   char *p = d8 + i;
  75   char *d = MAX (p, q);
  76
  77   d[7] = 0;         // { dg-warning "writing 2 bytes into a region of size 1" "" { target { vect_slp_v2qi_store_unalign } } }
  78   d[8] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
  79 }
  80
  81
  82 struct A3_5
  83 {
  84   char a3[3];  // { dg-message "at offset 3 into destination object 'a3' of size 3" "pr??????" { xfail *-*-* } }
  85   // refer to pr102697 for xfail
  86   char a5[5];  // { dg-message "at offset 5 into destination object 'a5' of size 5" "note" { xfail { vect_slp_v4qi_store_unalign } } }
  87 };
  88
  89 void max_A3_A5 (int i, struct A3_5 *pa3_5)
  90 {
  91   char *p = pa3_5->a3 + i;
  92   char *q = pa3_5->a5 + i;
  93
  94   char *d = MAX (p, q);
  95
  96   d[2] = 0;
  97   d[3] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "pr??????" { xfail *-*-* } }
  98   d[4] = 0;
  99   d[5] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "pr102697" { xfail { vect_slp_v4qi_store_unalign } } }
 100 }
 101
 102
 103 struct B4_B6
 104 {
 105   char b4[4];
 106   // refer to pr102697 for xfail
 107   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" { xfail { vect_slp_v4qi_store_unalign } } }
 108 };
 109
 110 void max_B6_B4 (int i, struct B4_B6 *pb4_b6)
 111 {
 112   char *p = pb4_b6->b6 + i;
 113   char *q = pb4_b6->b4 + i;
 114   char *d = MAX (p, q);
 115
 116   d[3] = 0;
 117   d[4] = 0;
 118   d[5] = 0;
 119   d[6] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "pr102697" { xfail { vect_slp_v4qi_store_unalign } } }
 120 }
 121
 122
 123 struct C7
 124 {
 125   char c7[7];       // { dg-message "at offset 7 into destination object 'c7' of size 7" "note"  { xfail { vect_slp_v2qi_store_unalign } } }
 126 };
 127
 128 void max_p_C7 (char *p, int i, struct C7 *pc7)
 129 {
 130   char *q = pc7->c7 + i;
 131   char *d = MAX (p, q);
 132
 133   d[6] = 0;
 134   d[7] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
 135 }
 136
 137
 138 struct D8
 139 {
 140   char d8[8];       // { dg-message "at offset 8 into destination object 'd8' of size 8" "note"  { xfail { vect_slp_v2qi_store_unalign } } }
 141 };
 142
 143 void max_D8_p (char *q, int i, struct D8 *pd8)
 144 {
 145   char *p = pd8->d8 + i;
 146   char *d = MAX (p, q);
 147
 148   d[7] = 0;
 149   d[8] = 0;         // { dg-warning "writing 1 byte into a region of size 0" "" { xfail { vect_slp_v2qi_store_unalign } } }
 150 }