1 /* Test for various situations where a new declaration of an
2 identifier conflicts with an earlier declaration which isn't in the
3 same scope. These are all undefined behavior per C89 sections
4 6.1.2.2p7, 6.1.2.6p2, and 6.3.2.2p2/footnote 38 (C99 6.2.2p7 and
5 6.2.7p2 - implicit declarations are invalid in C99). */
6
7 /* { dg-do compile } */
8 /* { dg-options "-std=c89 -pedantic -Wall -Wno-unused" } */
9
10 /* Extern at function scope, clashing with extern at file scope */
11
12 extern int foo1; /* { dg-message "note: previous" } */
13 extern int bar1(int); /* { dg-message "note: previous" } */
14
test1(void)15 void test1(void)
16 {
17 extern double foo1; /* { dg-error "conflict" } */
18 extern double bar1(double); /* { dg-error "conflict" } */
19 }
20
21 /* Extern at file scope, clashing with extern at function scope */
22
test2(void)23 void test2(void)
24 {
25 extern double foo2; /* { dg-message "note: previous" } */
26 extern double bar2(double); /* { dg-message "note: previous" } */
27 }
28
29 extern int foo2; /* { dg-error "conflict" } */
30 extern int bar2(int); /* { dg-error "conflict" } */
31
32 /* Extern at function scope, clashing with extern at earlier function
33 scope. Also, don't be fooled by a typedef at file scope. */
34
35 typedef float baz3; /* { dg-bogus } */
36
prime3(void)37 void prime3(void)
38 {
39 extern int foo3; /* { dg-message "note: previous" } */
40 extern int bar3(int); /* { dg-message "note: previous" } */
41 extern int baz3; /* { dg-message "note: previous" } */
42 }
43
test3(void)44 void test3(void)
45 {
46 extern double foo3; /* { dg-error "conflict" } */
47 extern double bar3(double); /* { dg-error "conflict" } */
48 extern double baz3; /* { dg-error "conflict" } */
49 }
50
51 /* Extern at function scope, clashing with previous implicit decl. */
52
prime4(void)53 void prime4(void)
54 {
55 bar4(); /* { dg-warning "implicit declaration of function" "implicit" } */
56 }
57
test4(void)58 void test4(void)
59 {
60 extern double bar4(double); /* { dg-error "conflict" } */
61 /* { dg-message "note: previous implicit declaration" "previous" { target *-*-* } 55 } */
62 }
63
64 /* Implicit decl, clashing with extern at previous function scope. */
65
prime5(void)66 void prime5(void)
67 {
68 extern double bar5(double); /* { dg-message "note: previous declaration" "previous 1" } */
69 } /* { dg-message "note: previous implicit declaration" "previous 2" { target *-*-* } 68 } */
70
test5(void)71 void test5(void)
72 {
73 bar5(1); /* { dg-warning "implicit declaration of function" } */
74 } /* { dg-error "incompatible implicit declaration" "" { target *-*-* } 73 } */
75
76 /* Extern then static, both at file scope. */
77
78 extern int test6(int); /* { dg-message "note: previous" "" } */
test6(int x)79 static int test6(int x) /* { dg-error "follows non-static" } */
80 { return x; }
81
82
83 /* Extern then static, extern at previous function scope. */
84
prime7(void)85 void prime7(void)
86 {
87 extern int test7(int); /* { dg-message "note: previous" "" } */
88 }
89
test7(int x)90 static int test7(int x) /* { dg-error "follows non-static" } */
91 { return x; }
92
93 /* Implicit decl then static. */
94
prime8(void)95 void prime8(void)
96 {
97 test8(); /* { dg-message "note: previous" "" } */
98 /* { dg-warning "implicit" "implicit" { target *-*-* } 97 } */
99 }
100
test8(int x)101 static int test8(int x) /* { dg-error "follows non-static" } */
102 { return x; }
103