1 /* PR c/83656 - missing -Wbuiltin-declaration-mismatch on declaration
2 without prototype
3 { dg-do compile }
4 { dg-options "-Wbuiltin-declaration-mismatch" } */
5
6 typedef __SIZE_TYPE__ size_t;
7
8 /* Built-ins declared without a prototype are not diagnosed by default
9 (without -Wextra) except when their return type doesn't match. */
10 int abort (); /* { dg-warning "\\\[-Wbuiltin-declaration-mismatch]" } */
11
12 /* Built-ins declared without a prototype are not diagnosed without -Wextra. */
13 void exit ();
14 void* memcpy ();
15 void* memset ();
16
17
test_call_abort(void)18 void test_call_abort (void)
19 {
20 /* Verify that a valid call to abort() is not diagnosed. */
21 abort ();
22
23 /* Unfortunately, the incompatible declaration above makes GCC "forget"
24 that abort() is a built-in and so the invalid calls below aren't
25 diagnosed. The only saving grace is that the invalid declaration
26 that differs in the return type is diagnosed by default. */
27 abort (1); /* { dg-warning "too many arguments to built-in function .abort. expecting 0" "pr?????" { xfail *-*-* } } */
28
29 abort (1, 2); /* { dg-warning "too many arguments" "pr?????" { xfail *-*-* } } */
30 }
31
32
test_call_exit(void)33 void test_call_exit (void)
34 {
35 /* Verify that valid calls to exit are not diagnosed. */
36 exit ('\0');
37 exit (0);
38
39 /* Also verify calls to the built-in. */
40 __builtin_exit ('\0');
41 __builtin_exit (0);
42 __builtin_exit (0.0);
43
44 exit (); /* { dg-warning "too few arguments to built-in function 'exit' expecting 1" } */
45
46 exit (1, 2); /* { dg-warning "too many arguments" } */
47
48 /* Verify that passing incompatible arguments triggers a warning. */
49 exit (""); /* { dg-warning "\\\[-Wint-conversion]" } */
50
51 struct S { int i; } s = { 0 };
52 exit (s); /* { dg-warning "incompatible type for argument 1" } */
53 }
54
55
test_call_memcpy(void * p,const void * q,size_t n)56 void test_call_memcpy (void *p, const void *q, size_t n)
57 {
58 memcpy (p, q, n);
59
60 memcpy (); /* { dg-warning "too few arguments to built-in function 'memcpy' expecting 3" } */
61
62 memcpy (p); /* { dg-warning "too few arguments to built-in function 'memcpy' expecting 3" } */
63
64 memcpy (p, q); /* { dg-warning "too few arguments to built-in function 'memcpy' expecting 3" } */
65
66 memcpy (q, p, n); /* { dg-warning "\\\[-Wdiscarded-qualifiers]" } */
67
68 memcpy (p, n, q); /* { dg-warning "\\\[-Wint-conversion]" } */
69
70 memcpy (p, q, n, 0); /* { dg-warning "too many arguments to built-in function 'memcpy' expecting 3" } */
71 }
72
73
74 typedef void* (memcpy_t)(void*, const void*, size_t);
75 typedef void* (memset_t)(void*, int, size_t);
76
test_init(void)77 void test_init (void)
78 {
79 /* Verify that initialization of a pointer by the address of a built-in
80 function of a matching type declared without a prototype doesn't
81 trigger a warning... */
82 memset_t *pmemset = memset;
83
84 /* ...but initialization by the address of an incompatible built-in
85 does even without -Wextra. */
86 memcpy_t *pmemcpy = memset; /* { dg-warning "\\\[-Wincompatible-pointer-types]" } */
87 }
88
89
test_assign(void)90 void test_assign (void)
91 {
92 /* Same as above but for assignment. */
93 memset_t *pmemset;
94 pmemset = memset;
95
96 memcpy_t *pmemcpy;
97 pmemcpy = memset; /* { dg-warning "\\\[-Wincompatible-pointer-types]" } */
98 }
99
100
101 /* Verify that passing built-ins declared without a prototype to
102 functions that expect a pointer to a function of a specific type
103 is diagnosed. Ditto for return statements. */
104
105 void take_memcpy (memcpy_t*);
106 void take_any (int, ...);
107
pass_args(int i)108 memset_t* pass_args (int i)
109 {
110 take_memcpy (memcpy);
111 take_memcpy (memset); /* { dg-warning "\\\[-Wincompatible-pointer-types]" } */
112
113 take_any (0, i ? memcpy : memset); /* { dg-warning "\\\[-Wincompatible-pointer-types]" } */
114
115 return memcpy; /* { dg-warning "\\\[-Wincompatible-pointer-types]" } */
116 }
117