/* Test for various situations where a new declaration of an identifier conflicts with an earlier declaration which isn't in the same scope. These are all undefined behavior per C89 sections 6.1.2.2p7, 6.1.2.6p2, and 6.3.2.2p2/footnote 38 (C99 6.2.2p7 and 6.2.7p2 - implicit declarations are invalid in C99). */ /* { dg-do compile } */ /* { dg-options "-std=c89 -pedantic -Wall -Wno-unused" } */ /* Extern at function scope, clashing with extern at file scope */ extern int foo1; /* { dg-error "previous" } */ extern int bar1(int); /* { dg-error "previous" } */ void test1(void) { extern double foo1; /* { dg-error "conflict" } */ extern double bar1(double); /* { dg-error "conflict" } */ } /* Extern at file scope, clashing with extern at function scope */ void test2(void) { extern double foo2; /* { dg-error "previous" } */ extern double bar2(double); /* { dg-error "previous" } */ } extern int foo2; /* { dg-error "conflict" } */ extern int bar2(int); /* { dg-error "conflict" } */ /* Extern at function scope, clashing with extern at earlier function scope. Also, don't be fooled by a typedef at file scope. */ typedef float baz3; /* { dg-bogus } */ void prime3(void) { extern int foo3; /* { dg-error "previous" } */ extern int bar3(int); /* { dg-error "previous" } */ extern int baz3; /* { dg-error "previous" } */ } void test3(void) { extern double foo3; /* { dg-error "conflict" } */ extern double bar3(double); /* { dg-error "conflict" } */ extern double baz3; /* { dg-error "conflict" } */ } /* Extern at function scope, clashing with previous implicit decl. */ void prime4(void) { bar4(); /* { dg-error "previous|implicit" } */ } void test4(void) { extern double bar4(double); /* { dg-error "conflict" } */ } /* Implicit decl, clashing with extern at previous function scope. */ void prime5(void) { extern double bar5(double); /* { dg-error "previous" "" } */ } void test5(void) { bar5(1); /* { dg-error "implicit" } */ } /* Extern then static, both at file scope. */ extern int test6(int); /* { dg-warning "previous" "" } */ static int test6(int x) { return x; } /* { dg-warning "follows non-static" } */ /* Extern then static, extern at previous function scope. */ void prime7(void) { extern int test7(int); /* { dg-warning "previous" "" } */ } static int test7(int x) { return x; } /* { dg-warning "follows non-static" } */ /* Implicit decl then static. */ void prime8(void) { test8(); /* { dg-warning "previous" "" } */ /* { dg-warning "implicit" "implicit" { target *-*-* } 96 } */ } static int test8(int x) { return x; } /* { dg-warning "follows non-static" } */