1 /* PR 85623 - strncmp() warns about attribute 'nonstring' incorrectly
2 in -Wstringop-overflow
3 { dg-do compile }
4 { dg-options "-O2 -Wstringop-overread -ftrack-macro-expansion=0" } */
5
6 #include "../gcc.dg/range.h"
7
8 #if __cplusplus
9 extern "C" {
10 #endif
11
12 extern int strcmp (const char*, const char*);
13 extern int strncmp (const char*, const char*, size_t);
14 extern int strncasecmp (const char*, const char*, size_t);
15
16 extern size_t strspn (const char*, const char*);
17 extern size_t strcspn (const char*, const char*);
18
19 #if __cplusplus
20 }
21 #endif
22
23 #define S26 "0123456789abcdefghijklmnopqrstuvwxyz"
24 #define S(n) (S26 + sizeof S26 - 1 - (n))
25
26 char __attribute__ ((nonstring)) a3[3];
27 char __attribute__ ((nonstring)) a5[5];
28
29 void sink (int);
30
31 #define T(call) sink (call)
32
33 void test_strcmp_cst (void)
34 {
35 /* Verify that no warning is issued for strcmp() calls with a non-string
36 array argument when the other argument is a string whose length is
37 less than the size of the array. Because the function stops reading
38 at the first nul character there is no chance that it will read past
39 the end of the array. */
40 T (strcmp (S (0), a3));
41 T (strcmp (S (1), a3));
42 T (strcmp (S (2), a3));
43 /* The following reads a3[3]. */
44 T (strcmp (S (3), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
45 /* The following also reads past the end of a3. */
46 T (strcmp (S (9), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
47
48 T (strcmp (a3, S (0)));
49 T (strcmp (a3, S (1)));
50 T (strcmp (a3, S (2)));
51 T (strcmp (a3, S (3))); /* { dg-warning "\\\[-Wstringop-overread" } */
52 T (strcmp (a3, S (9))); /* { dg-warning "\\\[-Wstringop-overread" } */
53 }
54
55
56 void test_strcmp_range (const char *s)
57 {
58 s = signed_value () < 0 ? S (0) : S (1);
59 T (strcmp (a3, s));
60
61 s = signed_value () < 0 ? S (0) : S (2);
62 T (strcmp (a3, s));
63
64 s = signed_value () < 0 ? S (0) : S (3);
65 T (strcmp (a3, s)); /* { dg-warning "\\\[-Wstringop-overread" } */
66
67 s = signed_value () < 0 ? S (1) : S (2);
68 T (strcmp (a3, s));
69
70 s = signed_value () < 0 ? S (1) : S (3);
71 T (strcmp (a3, s)); /* { dg-warning "\\\[-Wstringop-overread" } */
72
73 s = signed_value () < 0 ? S (3) : S (4);
74 T (strcmp (a3, s)); /* { dg-warning "\\\[-Wstringop-overread" } */
75 }
76
77
78 void test_strncmp_cst (void)
79 {
80 T (strncmp (S (0), a3, 1));
81 T (strncmp (S (1), a3, 2));
82 T (strncmp (S (2), a3, 3));
83 T (strncmp (S (3), a3, 3));
84 T (strncmp (S (3), a3, 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
85
86 T (strncmp (S (9), a3, 3));
87 T (strncmp (S (9), a3, 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
88 T (strncmp (S (9), a3, 5)); /* { dg-warning "\\\[-Wstringop-overread" } */
89
90 T (strncmp (a3, S (0), 1));
91 T (strncmp (a3, S (1), 2));
92 T (strncmp (a3, S (2), 3));
93 T (strncmp (a3, S (3), 3));
94 T (strncmp (a3, S (3), 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
95
96 T (strncmp (a3, S (9), 3));
97 T (strncmp (a3, S (9), 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
98 T (strncmp (a3, S (9), 5)); /* { dg-warning "\\\[-Wstringop-overread" } */
99 }
100
101 void test_strncmp_range (const char *s)
102 {
103 T (strncmp (a3, S (2), UR (0, 3)));
104 T (strncmp (a3, S (2), UR (1, 4)));
105 T (strncmp (a3, S (2), UR (2, 5)));
106 T (strncmp (a3, S (2), UR (3, 6)));
107 T (strncmp (a3, S (2), UR (4, 7)));
108
109 T (strncmp (a3, S (5), UR (0, 3)));
110 T (strncmp (a3, S (5), UR (1, 4)));
111 T (strncmp (a3, S (5), UR (2, 5)));
112 T (strncmp (a3, S (5), UR (3, 6)));
113 T (strncmp (a3, S (5), UR (4, 7))); /* { dg-warning "\\\[-Wstringop-overread" } */
114 T (strncmp (a3, S (5), UR (7, 9))); /* { dg-warning "\\\[-Wstringop-overread" } */
115
116 s = signed_value () < 0 ? S (0) : S (1);
117 T (strncmp (a3, s, UR (1, 3)));
118 T (strncmp (a3, s, UR (2, 5)));
119
120 s = signed_value () < 0 ? S (2) : S (5);
121 T (strncmp (a3, s, UR (1, 3)));
122
123 s = signed_value () < 0 ? S (2) : S (5);
124 T (strncmp (a3, s, UR (1, 4)));
125 T (strncmp (a3, s, UR (2, 5)));
126 T (strncmp (a3, s, UR (3, 6)));
127 T (strncmp (a3, s, UR (4, 7))); /* { dg-warning "\\\[-Wstringop-overread" } */
128 }
129
130 void test_strncasecmp (void)
131 {
132 T (strncasecmp (S (0), a3, 1));
133 T (strncasecmp (S (1), a3, 2));
134 T (strncasecmp (S (2), a3, 3));
135 T (strncasecmp (S (3), a3, 3));
136 T (strncasecmp (S (3), a3, 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
137
138 T (strncasecmp (S (9), a3, 3));
139 T (strncasecmp (S (9), a3, 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
140 T (strncasecmp (S (9), a3, 5)); /* { dg-warning "\\\[-Wstringop-overread" } */
141
142 T (strncasecmp (a3, S (0), 1));
143 T (strncasecmp (a3, S (1), 2));
144 T (strncasecmp (a3, S (2), 3));
145 T (strncasecmp (a3, S (3), 3));
146 T (strncasecmp (a3, S (3), 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
147
148 T (strncasecmp (a3, S (9), 3));
149 T (strncasecmp (a3, S (9), 4)); /* { dg-warning "\\\[-Wstringop-overread" } */
150 T (strncasecmp (a3, S (9), 5)); /* { dg-warning "\\\[-Wstringop-overread" } */
151 }
152
153 void test_strspn (void)
154 {
155 /* strspn must traverse all characters in the second argument except
156 when the first string is empty. */
157 T (strspn (S (0), a3));
158 T (strspn (S (1), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
159 T (strspn (S (2), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
160 T (strspn (S (3), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
161 T (strspn (S (9), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
162
163 /* Similarly, strspn must traverse all characters in the first argument
164 except when the second string is empty. */
165 T (strspn (a3, S (0)));
166 T (strspn (a3, S (1))); /* { dg-warning "\\\[-Wstringop-overread" } */
167 T (strspn (a3, S (2))); /* { dg-warning "\\\[-Wstringop-overread" } */
168 T (strspn (a3, S (3))); /* { dg-warning "\\\[-Wstringop-overread" } */
169 T (strspn (a3, S (9))); /* { dg-warning "\\\[-Wstringop-overread" } */
170 }
171
172 void test_strcspn (void)
173 {
174 T (strcspn (S (0), a3));
175 T (strcspn (S (1), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
176 T (strcspn (S (2), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
177 T (strcspn (S (3), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
178 T (strcspn (S (9), a3)); /* { dg-warning "\\\[-Wstringop-overread" } */
179
180 T (strcspn (a3, S (0))); /* { dg-warning "\\\[-Wstringop-overread" } */
181 T (strcspn (a3, S (1))); /* { dg-warning "\\\[-Wstringop-overread" } */
182 T (strcspn (a3, S (2))); /* { dg-warning "\\\[-Wstringop-overread" } */
183 T (strcspn (a3, S (3))); /* { dg-warning "\\\[-Wstringop-overread" } */
184 T (strcspn (a3, S (9))); /* { dg-warning "\\\[-Wstringop-overread" } */
185 }