Files
clang-p2996/clang/test/Sema/builtins.c
Richard Smith 552c6c2328 PR44406: Follow behavior of array bound constant folding in more recent versions of GCC.
Old GCC used to aggressively fold VLAs to constant-bound arrays at block
scope in GNU mode. That's non-conforming, and more modern versions of
GCC only do this at file scope. Update Clang to do the same.

Also promote the warning for this from off-by-default to on-by-default
in all cases; more recent versions of GCC likewise warn on this by
default.

This is still slightly more permissive than GCC, as pointed out in
PR44406, as we still fold VLAs to constant arrays in structs, but that
seems justifiable given that we don't support VLA-in-struct (and don't
intend to ever support it), but GCC does.

Differential Revision: https://reviews.llvm.org/D89523
2020-10-16 14:34:35 -07:00

382 lines
16 KiB
C

// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wstrlcpy-strlcat-size -Wno-string-plus-int -triple=i686-apple-darwin9
// This test needs to set the target because it uses __builtin_ia32_vec_ext_v4si
int test1(float a, int b) {
return __builtin_isless(a, b); // expected-note {{declared here}}
}
int test2(int a, int b) {
return __builtin_islessequal(a, b); // expected-error {{floating point type}}
}
int test3(double a, float b) {
return __builtin_isless(a, b);
}
int test4(int* a, double b) {
return __builtin_islessequal(a, b); // expected-error {{floating point type}}
}
int test5(float a, long double b) {
return __builtin_isless(a, b, b); // expected-error {{too many arguments}}
}
int test6(float a, long double b) {
return __builtin_islessequal(a); // expected-error {{too few arguments}}
}
#define CFSTR __builtin___CFStringMakeConstantString
void test7() {
const void *X;
X = CFSTR("\242"); // expected-warning {{input conversion stopped}}
X = CFSTR("\0"); // no-warning
X = CFSTR(242); // expected-error {{CFString literal is not a string constant}} expected-warning {{incompatible integer to pointer conversion}}
X = CFSTR("foo", "bar"); // expected-error {{too many arguments to function call}}
}
// atomics.
void test9(short v) {
unsigned i, old;
old = __sync_fetch_and_add(); // expected-error {{too few arguments to function call}}
old = __sync_fetch_and_add(&old); // expected-error {{too few arguments to function call}}
old = __sync_fetch_and_add((unsigned*)0, 42i); // expected-warning {{imaginary constants are a GNU extension}}
// PR7600: Pointers are implicitly casted to integers and back.
void *old_ptr = __sync_val_compare_and_swap((void**)0, 0, 0);
// Ensure the return type is correct even when implicit casts are stripped
// away. This triggers an assertion while checking the comparison otherwise.
if (__sync_fetch_and_add(&old, 1) == 1) {
}
}
// overloaded atomics should be declared only once.
void test9_1(volatile int* ptr, int val) {
__sync_fetch_and_add_4(ptr, val);
}
void test9_2(volatile int* ptr, int val) {
__sync_fetch_and_add(ptr, val);
}
void test9_3(volatile int* ptr, int val) {
__sync_fetch_and_add_4(ptr, val);
__sync_fetch_and_add(ptr, val);
__sync_fetch_and_add(ptr, val);
__sync_fetch_and_add_4(ptr, val);
__sync_fetch_and_add_4(ptr, val);
}
void test9_4(volatile int* ptr, int val) {
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_fetch_and_nand(ptr, val);
}
// rdar://7236819
void test10(void) __attribute__((noreturn));
void test10(void) {
__asm__("int3");
__builtin_unreachable();
// No warning about falling off the end of a noreturn function.
}
void test11(int X) {
switch (X) {
case __builtin_eh_return_data_regno(0): // constant foldable.
break;
}
__builtin_eh_return_data_regno(X); // expected-error {{argument to '__builtin_eh_return_data_regno' must be a constant integer}}
}
// PR5062
void test12(void) __attribute__((__noreturn__));
void test12(void) {
__builtin_trap(); // no warning because trap is noreturn.
}
void test_unknown_builtin(int a, int b) {
__builtin_isles(a, b); // expected-error{{use of unknown builtin}} \
// expected-note{{did you mean '__builtin_isless'?}}
}
int test13() {
__builtin_eh_return(0, 0); // no warning, eh_return never returns.
}
// <rdar://problem/8228293>
void test14() {
int old;
old = __sync_fetch_and_min((volatile int *)&old, 1);
}
// <rdar://problem/8336581>
void test15(const char *s) {
__builtin_printf("string is %s\n", s);
}
// PR7885
int test16() {
return __builtin_constant_p() + // expected-error{{too few arguments}}
__builtin_constant_p(1, 2); // expected-error {{too many arguments}}
}
// __builtin_constant_p cannot resolve non-constants as a file scoped array.
int expr;
char y[__builtin_constant_p(expr) ? -1 : 1]; // no warning, the builtin is false.
// no warning, the builtin is false.
struct foo { int a; };
struct foo x = (struct foo) { __builtin_constant_p(42) ? 37 : 927 };
const int test17_n = 0;
const char test17_c[] = {1, 2, 3, 0};
const char test17_d[] = {1, 2, 3, 4};
typedef int __attribute__((vector_size(16))) IntVector;
struct Aggregate { int n; char c; };
enum Enum { EnumValue1, EnumValue2 };
typedef __typeof(sizeof(int)) size_t;
size_t strlen(const char *);
void test17() {
#define ASSERT(...) { enum { folded = (__VA_ARGS__) }; int arr[folded ? 1 : -1]; }
#define T(...) ASSERT(__builtin_constant_p(__VA_ARGS__))
#define F(...) ASSERT(!__builtin_constant_p(__VA_ARGS__))
// __builtin_constant_p returns 1 if the argument folds to:
// - an arithmetic constant with value which is known at compile time
T(test17_n);
T(&test17_c[3] - test17_c);
T(3i + 5); // expected-warning {{imaginary constant}}
T(4.2 * 7.6);
T(EnumValue1);
T((enum Enum)(int)EnumValue2);
// - the address of the first character of a string literal, losslessly cast
// to any type
T("string literal");
T((double*)"string literal");
T("string literal" + 0);
T((long)"string literal");
// ... and otherwise returns 0.
F("string literal" + 1);
F(&test17_n);
F(test17_c);
F(&test17_c);
F(&test17_d);
F((struct Aggregate){0, 1});
F((IntVector){0, 1, 2, 3});
F(test17);
// Ensure that a technique used in glibc is handled correctly.
#define OPT(...) (__builtin_constant_p(__VA_ARGS__) && strlen(__VA_ARGS__) < 4)
// FIXME: These are incorrectly treated as ICEs because strlen is treated as
// a builtin.
ASSERT(OPT("abc"));
ASSERT(!OPT("abcd"));
// In these cases, the strlen is non-constant, but the __builtin_constant_p
// is 0: the array size is not an ICE but is foldable.
ASSERT(!OPT(test17_c)); // expected-warning {{folding}}
ASSERT(!OPT(&test17_c[0])); // expected-warning {{folding}}
ASSERT(!OPT((char*)test17_c)); // expected-warning {{folding}}
ASSERT(!OPT(test17_d)); // expected-warning {{folding}}
ASSERT(!OPT(&test17_d[0])); // expected-warning {{folding}}
ASSERT(!OPT((char*)test17_d)); // expected-warning {{folding}}
#undef OPT
#undef T
#undef F
}
void test18() {
char src[1024];
char dst[2048];
size_t result;
void *ptr;
ptr = __builtin___memccpy_chk(dst, src, '\037', sizeof(src), sizeof(dst));
result = __builtin___strlcpy_chk(dst, src, sizeof(dst), sizeof(dst));
result = __builtin___strlcat_chk(dst, src, sizeof(dst), sizeof(dst));
ptr = __builtin___memccpy_chk(dst, src, '\037', sizeof(src)); // expected-error {{too few arguments to function call}}
ptr = __builtin___strlcpy_chk(dst, src, sizeof(dst), sizeof(dst)); // expected-warning {{incompatible integer to pointer conversion}}
ptr = __builtin___strlcat_chk(dst, src, sizeof(dst), sizeof(dst)); // expected-warning {{incompatible integer to pointer conversion}}
}
void no_ms_builtins() {
__assume(1); // expected-warning {{implicit declaration}}
__noop(1); // expected-warning {{implicit declaration}}
__debugbreak(); // expected-warning {{implicit declaration}}
}
void unavailable() {
__builtin_operator_new(0); // expected-error {{'__builtin_operator_new' is only available in C++}}
__builtin_operator_delete(0); // expected-error {{'__builtin_operator_delete' is only available in C++}}
}
// rdar://18259539
size_t strlcpy(char * restrict dst, const char * restrict src, size_t size);
size_t strlcat(char * restrict dst, const char * restrict src, size_t size);
void Test19(void)
{
static char b[40];
static char buf[20];
strlcpy(buf, b, sizeof(b)); // expected-warning {{size argument in 'strlcpy' call appears to be size of the source; expected the size of the destination}} \\
// expected-note {{change size argument to be the size of the destination}}
__builtin___strlcpy_chk(buf, b, sizeof(b), __builtin_object_size(buf, 0)); // expected-warning {{size argument in '__builtin___strlcpy_chk' call appears to be size of the source; expected the size of the destination}} \
// expected-note {{change size argument to be the size of the destination}} \
// expected-warning {{'strlcpy' will always overflow; destination buffer has size 20, but size argument is 40}}
strlcat(buf, b, sizeof(b)); // expected-warning {{size argument in 'strlcat' call appears to be size of the source; expected the size of the destination}} \
// expected-note {{change size argument to be the size of the destination}}
__builtin___strlcat_chk(buf, b, sizeof(b), __builtin_object_size(buf, 0)); // expected-warning {{size argument in '__builtin___strlcat_chk' call appears to be size of the source; expected the size of the destination}} \
// expected-note {{change size argument to be the size of the destination}} \
// expected-warning {{'strlcat' will always overflow; destination buffer has size 20, but size argument is 40}}
}
// rdar://11076881
char * Test20(char *p, const char *in, unsigned n)
{
static char buf[10];
__builtin___memcpy_chk (&buf[6], in, 5, __builtin_object_size (&buf[6], 0)); // expected-warning {{'memcpy' will always overflow; destination buffer has size 4, but size argument is 5}}
__builtin___memcpy_chk (p, "abcde", n, __builtin_object_size (p, 0));
__builtin___memcpy_chk (&buf[5], "abcde", 5, __builtin_object_size (&buf[5], 0));
__builtin___memcpy_chk (&buf[5], "abcde", n, __builtin_object_size (&buf[5], 0));
__builtin___memcpy_chk (&buf[6], "abcde", 5, __builtin_object_size (&buf[6], 0)); // expected-warning {{'memcpy' will always overflow; destination buffer has size 4, but size argument is 5}}
return buf;
}
typedef void (fn_t)(int);
void test_builtin_launder(char *p, void *vp, const void *cvp,
const volatile int *ip, float *restrict fp,
fn_t *fn) {
__builtin_launder(); // expected-error {{too few arguments to function call, expected 1, have 0}}
__builtin_launder(p, p); // expected-error {{too many arguments to function call, expected 1, have 2}}
int x;
__builtin_launder(x); // expected-error {{non-pointer argument to '__builtin_launder' is not allowed}}
char *d = __builtin_launder(p);
__builtin_launder(vp); // expected-error {{void pointer argument to '__builtin_launder' is not allowed}}
__builtin_launder(cvp); // expected-error {{void pointer argument to '__builtin_launder' is not allowed}}
const volatile int *id = __builtin_launder(ip);
int *id2 = __builtin_launder(ip); // expected-warning {{discards qualifiers}}
float *fd = __builtin_launder(fp);
__builtin_launder(fn); // expected-error {{function pointer argument to '__builtin_launder' is not allowed}}
}
void test21(const int *ptr) {
__sync_fetch_and_add(ptr, 1); // expected-error{{address argument to atomic builtin cannot be const-qualified ('const int *' invalid)}}
__atomic_fetch_add(ptr, 1, 0); // expected-error {{address argument to atomic operation must be a pointer to non-const type ('const int *' invalid)}}
}
void test_ei_i42i(_ExtInt(42) *ptr, int value) {
__sync_fetch_and_add(ptr, value); // expected-error {{Atomic memory operand must have a power-of-two size}}
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_nand_and_fetch(ptr, value); // expected-error {{Atomic memory operand must have a power-of-two size}}
__atomic_fetch_add(ptr, 1, 0); // expected-error {{argument to atomic builtin of type '_ExtInt' is not supported}}
}
void test_ei_i64i(_ExtInt(64) *ptr, int value) {
__sync_fetch_and_add(ptr, value); // expect success
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_nand_and_fetch(ptr, value); // expect success
__atomic_fetch_add(ptr, 1, 0); // expected-error {{argument to atomic builtin of type '_ExtInt' is not supported}}
}
void test_ei_ii42(int *ptr, _ExtInt(42) value) {
__sync_fetch_and_add(ptr, value); // expect success
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_nand_and_fetch(ptr, value); // expect success
}
void test_ei_ii64(int *ptr, _ExtInt(64) value) {
__sync_fetch_and_add(ptr, value); // expect success
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_nand_and_fetch(ptr, value); // expect success
}
void test_ei_i42i42(_ExtInt(42) *ptr, _ExtInt(42) value) {
__sync_fetch_and_add(ptr, value); // expected-error {{Atomic memory operand must have a power-of-two size}}
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_nand_and_fetch(ptr, value); // expected-error {{Atomic memory operand must have a power-of-two size}}
}
void test_ei_i64i64(_ExtInt(64) *ptr, _ExtInt(64) value) {
__sync_fetch_and_add(ptr, value); // expect success
// expected-warning@+1 {{the semantics of this intrinsic changed with GCC version 4.4 - the newer semantics are provided here}}
__sync_nand_and_fetch(ptr, value); // expect success
}
void test22(void) {
(void)__builtin_signbit(); // expected-error{{too few arguments to function call, expected 1, have 0}}
(void)__builtin_signbit(1.0, 2.0, 3.0); // expected-error{{too many arguments to function call, expected 1, have 3}}
(void)__builtin_signbit(1); // expected-error {{floating point classification requires argument of floating point type (passed in 'int')}}
(void)__builtin_signbit(1.0);
(void)__builtin_signbit(1.0f);
(void)__builtin_signbit(1.0L);
(void)__builtin_signbitf(); // expected-error{{too few arguments to function call, expected 1, have 0}}
(void)__builtin_signbitf(1.0, 2.0, 3.0); // expected-error{{too many arguments to function call, expected 1, have 3}}
(void)__builtin_signbitf(1);
(void)__builtin_signbitf(1.0);
(void)__builtin_signbitf(1.0f);
(void)__builtin_signbitf(1.0L);
(void)__builtin_signbitl(); // expected-error{{too few arguments to function call, expected 1, have 0}}
(void)__builtin_signbitl(1.0, 2.0, 3.0); // expected-error{{too many arguments to function call, expected 1, have 3}}
(void)__builtin_signbitl(1);
(void)__builtin_signbitl(1.0);
(void)__builtin_signbitl(1.0f);
(void)__builtin_signbitl(1.0L);
}
// rdar://43909200
#define memcpy(x,y,z) __builtin___memcpy_chk(x,y,z, __builtin_object_size(x,0))
#define my_memcpy(x,y,z) __builtin___memcpy_chk(x,y,z, __builtin_object_size(x,0))
void test23() {
char src[1024];
char buf[10];
memcpy(buf, src, 11); // expected-warning{{'memcpy' will always overflow; destination buffer has size 10, but size argument is 11}}
my_memcpy(buf, src, 11); // expected-warning{{'memcpy' will always overflow; destination buffer has size 10, but size argument is 11}}
}
// Test that __builtin_is_constant_evaluated() is not allowed in C
int test_cxx_builtin() {
// expected-error@+1 {{use of unknown builtin '__builtin_is_constant_evaluated'}}
return __builtin_is_constant_evaluated();
}
void test_builtin_complex() {
__builtin_complex(); // expected-error {{too few}}
__builtin_complex(1); // expected-error {{too few}}
__builtin_complex(1, 2, 3); // expected-error {{too many}}
_Static_assert(_Generic(__builtin_complex(1.0f, 2.0f), _Complex float: 1, default: 0), "");
_Static_assert(_Generic(__builtin_complex(1.0, 2.0), _Complex double: 1, default: 0), "");
_Static_assert(_Generic(__builtin_complex(1.0l, 2.0l), _Complex long double: 1, default: 0), "");
__builtin_complex(1, 2); // expected-error {{argument type 'int' is not a real floating point type}}
__builtin_complex(1, 2.0); // expected-error {{argument type 'int' is not a real floating point type}}
__builtin_complex(1.0, 2); // expected-error {{argument type 'int' is not a real floating point type}}
__builtin_complex(1.0, 2.0f); // expected-error {{arguments are of different types ('double' vs 'float')}}
__builtin_complex(1.0f, 2.0); // expected-error {{arguments are of different types ('float' vs 'double')}}
}
_Complex double builtin_complex_static_init = __builtin_complex(1.0, 2.0);