llvm-project/clang/test/Sema/warn-cast-align.c

78 lines
1.9 KiB
C

// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fsyntax-only -Wcast-align -verify %s
// Simple casts.
void test0(char *P) {
char *a = (char*) P;
short *b = (short*) P; // expected-warning {{cast from 'char *' to 'short *' increases required alignment from 1 to 2}}
int *c = (int*) P; // expected-warning {{cast from 'char *' to 'int *' increases required alignment from 1 to 4}}
}
// Casts from void* are a special case.
void test1(void *P) {
char *a = (char*) P;
short *b = (short*) P;
int *c = (int*) P;
const volatile void *P2 = P;
char *d = (char*) P2;
short *e = (short*) P2;
int *f = (int*) P2;
const char *g = (const char*) P2;
const short *h = (const short*) P2;
const int *i = (const int*) P2;
const volatile char *j = (const volatile char*) P2;
const volatile short *k = (const volatile short*) P2;
const volatile int *l = (const volatile int*) P2;
}
// Aligned struct.
struct __attribute__((aligned(16))) A {
char buffer[16];
};
void test2(char *P) {
struct A *a = (struct A*) P; // expected-warning {{cast from 'char *' to 'struct A *' increases required alignment from 1 to 16}}
}
// Incomplete type.
void test3(char *P) {
struct B *b = (struct B*) P;
}
// Do not issue a warning. The aligned attribute changes the alignment of the
// variables and fields.
char __attribute__((aligned(4))) a[16];
struct S0 {
char a[16];
};
struct S {
char __attribute__((aligned(4))) a[16];
struct S0 __attribute__((aligned(4))) s0;
};
void test4() {
struct S s;
int *i = (int *)s.a;
i = (int *)&s.s0;
i = (int *)a;
}
// No warnings.
typedef int (*FnTy)(void);
unsigned int func5(void);
FnTy test5(void) {
return (FnTy)&func5;
}
void test6() {
struct {
int hello;
doesnotexist world; // expected-error {{unknown type name 'doesnotexist'}}
} foo;
void **repro = (void **)&foo.hello; // expected-warning {{cast from 'int *' to 'void **' increases required alignment from 4 to 8}}
}