1 /* PR tree-optimization/83776: missing -Warray-bounds indexing past the end
2 of a string literal
3 Test to exercise warnings for computations of otherwise in-bounds indices
4 into strings that temporarily exceed the bounds of the string.
5 { dg-do compile }
6 { dg-options "-O2 -Warray-bounds=2 -ftrack-macro-expansion=0" } */
7
8 #include "range.h"
9
10 #define MAX DIFF_MAX
11 #define MIN DIFF_MIN
12
13 typedef __WCHAR_TYPE__ wchar_t;
14
15 void sink (int, ...);
16
17 #define T(expr) sink (0, expr)
18
19 void test_narrow (void)
20 {
21 int i = SR (1, 2);
22
23 const char *p0 = "12";
24 const char *p1 = p0 + i; /* points at '2' or beyond */
25 const char *p2 = p1 + i; /* points at '\0' or beyond */
26 const char *p3 = p2 + i; /* points just past the end */
27 const char *p4 = p3 + i; /* invalid */
28
29 T (p0[-1]); /* { dg-warning "array subscript \(-1|\[0-9\]+) is outside array bounds of .char\\\[3]." } */
30 T (p0[0]);
31 T (p0[1]);
32 T (p0[2]);
33 T (p0[3]); /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
34
35 T (&p0[-1]); /* { dg-warning "array subscript \(-1|\[0-9\]+) is \(above|below|outside\) array bounds of .char\\\[3]." } */
36 T (&p0[0]);
37 T (&p0[1]);
38 T (&p0[2]);
39 T (&p0[3]);
40 T (&p0[4]); /* { dg-warning "array subscript 4 is \(above|outside\) array bounds of .char\\\[3]." } */
41
42 T (p1[-3]); /* { dg-warning "array subscript \\\[-2, -1] is outside array bounds of .char\\\[3]." } */
43 T (p1[-2]);
44 T (p1[-1]);
45 T (p1[ 0]);
46 T (p1[ 1]);
47 T (p1[ 2]); /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
48 T (p1[ 3]); /* { dg-warning "array subscript \\\[4, 5] is outside array bounds of .char\\\[3]." } */
49
50 T (&p1[-3]); /* { dg-warning "array subscript \\\[-2, -1] is outside array bounds of .char\\\[3]." "bug" { xfail *-*-* } } */
51 T (&p1[-2]);
52 T (&p1[-1]);
53 T (&p1[ 0]);
54 T (&p1[ 1]);
55 T (&p1[ 2]);
56 T (&p1[ 3]); /* { dg-warning "array subscript \\\[4, 6] is outside array bounds of .char\\\[3]." "bug" { xfail *-*-* } } */
57
58 T (p2[-4]); /* { dg-warning "subscript \\\[-2, -1\\\] is outside array bounds of .char\\\[3]." } */
59 T (p2[-3]);
60 T (p2[-2]);
61 T (p2[-1]);
62 T (p2[ 0]);
63
64 /* Even though the lower bound of p3's offsets is in bounds, in order
65 to subtract 4 from p3 and get a dereferenceable pointer its value
66 would have to be out-of-bounds. */
67 T (p3[-4]); /* { dg-warning "array subscript -1 is outside array bounds of .char\\\[3]." } */
68 T (p3[-3]);
69 T (p3[-2]);
70 T (p3[-1]);
71 T (p3[ 0]); /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
72
73 T (p4[-4]); /* { dg-warning "intermediate array offset 4 is outside array bounds of .char\\\[3]." } */
74 T (p4[-3]); /* { dg-warning "intermediate array offset 4 is outside array bounds of .char\\\[3]." } */
75 T (p4[-2]); /* { dg-warning "intermediate array offset 4 is outside array bounds of .char\\\[3]." } */
76
77 /* The final subscripts below are invalid. */
78 T (p4[-1]); /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
79 T (p4[ 0]); /* { dg-warning "array subscript \\\[4, 5] is outside array bounds of .char\\\[3]." } */
80 }
81
82
83 void test_narrow_vflow (void)
84 {
85 int i = SR (DIFF_MAX - 2, DIFF_MAX);
86 int j = SR (1, DIFF_MAX);
87
88 const char *p0 = "123";
89 const char *p1 = p0 + i; /* points at '2' or beyond */
90 const char *p2 = p1 + i; /* points at '\0' or beyond */
91 const char *p3 = p2 + i; /* points just past the end */
92 const char *p4 = p3 + i; /* invalid */
93 }
94
95
96 void test_wide (void)
97 {
98 int i = SR (1, 2);
99
100 const wchar_t *p0 = L"123";
101 const wchar_t *p1 = p0 + i; /* points at L'2' or beyond */
102 const wchar_t *p2 = p1 + i; /* points at L'3' or beyond */
103 const wchar_t *p3 = p2 + i; /* points at L'\0' or beyond */
104 const wchar_t *p4 = p3 + i; /* points just past the end */
105 const wchar_t *p5 = p4 + i; /* invalid */
106
107 T (p0[0]);
108 T (p0[1]);
109 T (p0[2]);
110 T (p0[3]);
111 T (p0[4]); /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
112
113 T (p1[-1]);
114 T (p1[ 0]);
115 T (p1[ 1]);
116 T (p1[ 2]);
117 T (p1[ 3]); /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
118
119 T (&p1[-1]);
120 T (&p1[ 0]);
121 T (&p1[ 1]);
122 T (&p1[ 2]);
123 T (&p1[ 3]);
124 T (&p1[ 4]); /* { dg-warning "array subscript \\\[5, 6] is outside array bounds of .\[a-z \]+\\\[4]." "bug" { xfail *-*-* } } */
125
126 T (p2[-5]); /* { dg-warning "array subscript \\\[-3, -1] is outside array bounds of .\[a-z \]+\\\[4]." } */
127 T (p2[-4]);
128 T (p2[-3]);
129 T (p2[-2]);
130 T (p2[-1]);
131 T (p2[ 0]);
132
133 /* Even though the lower bound of p3's offsets is in bounds, in order
134 to subtract 5 from p3 and get a dereferenceable pointer its value
135 would have to be out-of-bounds. */
136 T (p3[-5]); /* { dg-warning "array subscript \\\[-2, -1\\\] is outside array bounds of .\[a-z \]+\\\[4]." } */
137 T (p3[-4]);
138 T (p3[-3]);
139 T (p3[-2]);
140 T (p3[-1]);
141 T (p3[ 0]);
142 T (p3[ 1]); /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
143
144 T (p4[-5]); /* { dg-warning "array subscript -1 is outside array bounds of .\[a-z \]+\\\[4]." } */
145 T (p4[-4]);
146 T (p4[-3]);
147 T (p4[-2]);
148 T (p4[-1]);
149 T (p4[ 0]); /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
150 }