// RUN: %clang_cc1 -Wuninitialized -Wconditional-uninitialized -fsyntax-only -fblocks %s -verify
// RUN: %clang_cc1 -Wuninitialized -Wconditional-uninitialized -ftrivial-auto-var-init=pattern -fsyntax-only -fblocks %s -verify
typedef __typeof(sizeof(int)) size_t;
void *malloc(size_t);
int test1(void) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
return x; // expected-warning{{variable 'x' is uninitialized when used here}}
}
int test2(void) {
int x = 0;
return x; // no-warning
}
int test3(void) {
int x;
x = 0;
return x; // no-warning
}
int test4(void) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
++x; // expected-warning{{variable 'x' is uninitialized when used here}}
return x;
}
int test5(void) {
int x, y; // expected-note{{initialize the variable 'y' to silence this warning}}
x = y; // expected-warning{{variable 'y' is uninitialized when used here}}
return x;
}
int test6(void) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
x += 2; // expected-warning{{variable 'x' is uninitialized when used here}}
return x;
}
int test7(int y) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
if (y) // expected-warning{{variable 'x' is used uninitialized whenever 'if' condition is false}} \
// expected-note{{remove the 'if' if its condition is always true}}
x = 1;
return x; // expected-note{{uninitialized use occurs here}}
}
int test7b(int y) {
int x = x; // expected-note{{variable 'x' is declared here}}
if (y)
x = 1;
// Warn with "may be uninitialized" here (not "is sometimes uninitialized"),
// since the self-initialization is intended to suppress a -Wuninitialized
// warning.
return x; // expected-warning{{variable 'x' may be uninitialized when used here}}
}
int test8(int y) {
int x;
if (y)
x = 1;
else
x = 0;
return x;
}
int test9(int n) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
for (unsigned i = 0 ; i < n; ++i) {
if (i == n - 1)
break;
x = 1;
}
return x; // expected-warning{{variable 'x' may be uninitialized when used here}}
}
int test10(unsigned n) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
for (unsigned i = 0 ; i < n; ++i) {
x = 1;
}
return x; // expected-warning{{variable 'x' may be uninitialized when used here}}
}
int test11(unsigned n) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
for (unsigned i = 0 ; i <= n; ++i) {
x = 1;
}
return x; // expected-warning{{variable 'x' may be uninitialized when used here}}
}
void test12(unsigned n) {
for (unsigned i ; n ; ++i) ; // expected-warning{{variable 'i' is uninitialized when used here}} expected-note{{initialize the variable 'i' to silence this warning}}
}
int test13(void) {
static int i;
return i; // no-warning
}
// Simply don't crash on this test case.
void test14(void) {
const char *p = 0;
for (;;) {}
}
void test15(void) {
int x = x; // no-warning: signals intended lack of initialization.
}
int test15b(void) {
// Warn here with the self-init, since it does result in a use of
// an uninitialized variable and this is the root cause.
int x = x; // expected-warning {{variable 'x' is uninitialized when used within its own initialization}}
return x;
}
// Don't warn in the following example; shows dataflow confluence.
char *test16_aux(void);
void test16(void) {
char *p = test16_aux();
for (unsigned i = 0 ; i < 100 ; i++)
p[i] = 'a'; // no-warning
}
void test17(void) {
// Don't warn multiple times about the same uninitialized variable
// along the same path.
int *x; // expected-note{{initialize the variable 'x' to silence this warning}}
*x = 1; // expected-warning{{variable 'x' is uninitialized when used here}}
*x = 1; // no-warning
}
int test18(int x, int y) {
int z;
if (x && y && (z = 1)) {
return z; // no-warning
}
return 0;
}
int test19_aux1(void);
int test19_aux2(void);
int test19_aux3(int *x);
int test19(void) {
int z;
if (test19_aux1() + test19_aux2() && test19_aux1() && test19_aux3(&z))
return z; // no-warning
return 0;
}
int test20(void) {
int z; // expected-note{{initialize the variable 'z' to silence this warning}}
if ((test19_aux1() + test19_aux2() && test19_aux1()) || test19_aux3(&z)) // expected-warning {{variable 'z' is used uninitialized whenever '||' condition is true}} expected-note {{remove the '||' if its condition is always false}}
return z; // expected-note {{uninitialized use occurs here}}
return 0;
}
int test21(int x, int y) {
int z; // expected-note{{initialize the variable 'z' to silence this warning}}
if ((x && y) || test19_aux3(&z) || test19_aux2()) // expected-warning {{variable 'z' is used uninitialized whenever '||' condition is true}} expected-note {{remove the '||' if its condition is always false}}
return z; // expected-note {{uninitialized use occurs here}}
return 0;
}
int test22(void) {
int z;
while (test19_aux1() + test19_aux2() && test19_aux1() && test19_aux3(&z))
return z; // no-warning
return 0;
}
int test23(void) {
int z;
for ( ; test19_aux1() + test19_aux2() && test19_aux1() && test19_aux3(&z) ; )
return z; // no-warning
return 0;
}
// The basic uninitialized value analysis doesn't have enough path-sensitivity
// to catch initializations relying on control-dependencies spanning multiple
// conditionals. This possibly can be handled by making the CFG itself
// represent such control-dependencies, but it is a niche case.
int test24(int flag) {
unsigned val; // expected-note{{initialize the variable 'val' to silence this warning}}
if (flag)
val = 1;
if (!flag)
val = 1;
return val; // expected-warning{{variable 'val' may be uninitialized when used here}}
}
float test25(void) {
float x; // expected-note{{initialize the variable 'x' to silence this warning}}
return x; // expected-warning{{variable 'x' is uninitialized when used here}}
}
typedef int MyInt;
MyInt test26(void) {
MyInt x; // expected-note{{initialize the variable 'x' to silence this warning}}
return x; // expected-warning{{variable 'x' is uninitialized when used here}}
}
// Test handling of sizeof().
int test27(void) {
struct test_27 { int x; } *y;
return sizeof(y->x); // no-warning
}
int test28(void) {
int len; // expected-note{{initialize the variable 'len' to silence this warning}}
return sizeof(int[len]); // expected-warning{{variable 'len' is uninitialized when used here}}
}
void test29(void) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
(void) ^{ (void) x; }; // expected-warning{{variable 'x' is uninitialized when captured by block}}
}
void test30(void) {
static int x; // no-warning
(void) ^{ (void) x; };
}
void test31(void) {
__block int x; // no-warning
(void) ^{ (void) x; };
}
int test32_x;
void test32(void) {
(void) ^{ (void) test32_x; }; // no-warning
}
void test_33(void) {
int x; // no-warning
(void) x;
}
int test_34(void) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
(void) x;
return x; // expected-warning{{variable 'x' is uninitialized when used here}}
}
// Test that this case doesn't crash.
void test35(int x) {
__block int y = 0;
^{ y = (x == 0); }();
}
// Test handling of indirect goto.
void test36(void)
{
void **pc; // expected-note{{initialize the variable 'pc' to silence this warning}}
void *dummy[] = { &&L1, &&L2 };
L1:
goto *pc; // expected-warning{{variable 'pc' is uninitialized when used here}}
L2:
goto *pc;
}
// Test && nested in ||.
int test37_a(void);
int test37_b(void);
int test37(void)
{
int identifier;
if ((test37_a() && (identifier = 1)) ||
(test37_b() && (identifier = 2))) {
return identifier; // no-warning
}
return 0;
}
// Test merging of path-specific dataflow values (without asserting).
int test38(int r, int x, int y)
{
int z;
return ((r < 0) || ((r == 0) && (x < y)));
}
int test39(int x) {
int y; // expected-note{{initialize the variable 'y' to silence this warning}}
int z = x + y; // expected-warning {{variable 'y' is uninitialized when used here}}
return z;
}
int test40(int x) {
int y; // expected-note{{initialize the variable 'y' to silence this warning}}
return x ? 1 : y; // expected-warning {{variable 'y' is uninitialized when used here}}
}
int test41(int x) {
int y; // expected-note{{initialize the variable 'y' to silence this warning}}
if (x) y = 1; // expected-warning{{variable 'y' is used uninitialized whenever 'if' condition is false}} \
// expected-note{{remove the 'if' if its condition is always true}}
return y; // expected-note{{uninitialized use occurs here}}
}
void test42(void) {
int a;
a = 30; // no-warning
}
void test43_aux(int x);
void test43(int i) {
int x; // expected-note{{initialize the variable 'x' to silence this warning}}
for (i = 0 ; i < 10; i++)
test43_aux(x++); // expected-warning {{variable 'x' is uninitialized when used here}}
}
void test44(int i) {
int x = i;
int y; // expected-note{{initialize the variable 'y' to silence this warning}}
for (i = 0; i < 10; i++ ) {
test43_aux(x++); // no-warning
x += y; // expected-warning {{variable 'y' is uninitialized when used here}}
}
}
int test45(int j) {
int x = 1, y = x + 1;
if (y) // no-warning
return x;
return y;
}
void test46(void)
{
int i; // expected-note{{initialize the variable 'i' to silence this warning}}
int j = i ? : 1; // expected-warning {{variable 'i' is uninitialized when used here}}
}
void *test47(int *i)
{
return i ? : 0; // no-warning
}
void *test49(int *i)
{
int a;
return &a ? : i; // no-warning
}
void test50(void)
{
char c[1 ? : 2]; // no-warning
}
int test51(void)
{
__block int a;
^(void) {
a = 42;
}();
return a; // no-warning
}
// FIXME: This is a false positive, but it tests logical operations in switch statements.
int test52(int a, int b) {
int x; // expected-note {{initialize the variable 'x' to silence this warning}}
switch (a || b) { // expected-warning {{switch condition has boolean value}}
case 0:
x = 1;
break;
case 1:
x = 2;
break;
}
return x; // expected-warning {{variable 'x' may be uninitialized when used here}}
}
void test53(void) {
int x; // expected-note {{initialize the variable 'x' to silence this warning}}
int y = (x); // expected-warning {{variable 'x' is uninitialized when used here}}
}
// This CFG caused the uninitialized values warning to inf-loop.
extern int PR10379_g(void);
void PR10379_f(int *len) {
int new_len; // expected-note{{initialize the variable 'new_len' to silence this warning}}
for (int i = 0; i < 42 && PR10379_g() == 0; i++) {
if (PR10379_g() == 1)
continue;
if (PR10379_g() == 2)
PR10379_f(&new_len);
else if (PR10379_g() == 3)
PR10379_f(&new_len);
*len += new_len; // expected-warning {{variable 'new_len' may be uninitialized when used here}}
}
}
// Test that sizeof(VLA) doesn't trigger a warning.
void test_vla_sizeof(int x) {
double (*memory)[2][x] = malloc(sizeof(*memory)); // no-warning
}
// Test absurd case of deadcode + use of blocks. This previously was a false positive
// due to an analysis bug.
int test_block_and_dead_code(void) {
__block int x;
^{ x = 1; }();
if (0)
return x;
return x; // no-warning
}
// This previously triggered an infinite loop in the analysis.
void PR11069(int a, int b) {
unsigned long flags;
for (;;) {
if (a && !b)
break;
}
for (;;) {
// This does not trigger a warning because it isn't a real use.
(void)(flags); // no-warning
}
}
// Test uninitialized value used in loop condition.
void rdar9432305(float *P) {
int i; // expected-note {{initialize the variable 'i' to silence this warning}}
for (; i < 10000; ++i) // expected-warning {{variable 'i' is uninitialized when used here}}
P[i] = 0.0f;
}
// Test that fixits are not emitted inside macros.
#define UNINIT(T, x, y) T x; T y = x;
#define ASSIGN(T, x, y) T y = x;
void test54(void) {
UNINIT(int, a, b); // expected-warning {{variable 'a' is uninitialized when used here}} \
// expected-note {{variable 'a' is declared here}}
int c; // expected-note {{initialize the variable 'c' to silence this warning}}
ASSIGN(int, c, d); // expected-warning {{variable 'c' is uninitialized when used here}}
}
// Taking the address is fine
struct { struct { void *p; } a; } test55 = { { &test55.a }}; // no-warning
struct { struct { void *p; } a; } test56 = { { &(test56.a) }}; // no-warning
void uninit_in_loop(void) {
int produce(void);
void consume(int);
for (int n = 0; n < 100; ++n) {
int k; // expected-note {{initialize}}
consume(k); // expected-warning {{variable 'k' is uninitialized}}
k = produce();
}
}
void uninit_in_loop_goto(void) {
int produce(void);
void consume(int);
for (int n = 0; n < 100; ++n) {
goto skip_decl;
int k; // expected-note {{initialize}}
skip_decl:
// FIXME: This should produce the 'is uninitialized' diagnostic, but we
// don't have enough information in the CFG to easily tell that the
// variable's scope has been left and re-entered.
consume(k); // expected-warning {{variable 'k' may be uninitialized}}
k = produce();
}
}
typedef char jmp_buf[256];
extern int setjmp(jmp_buf env); // implicitly returns_twice
void do_stuff_and_longjmp(jmp_buf env, int *result) __attribute__((noreturn));
int returns_twice(void) {
int a; // expected-note {{initialize}}
if (!a) { // expected-warning {{variable 'a' is uninitialized}}
jmp_buf env;
int b;
if (setjmp(env) == 0) {
do_stuff_and_longjmp(env, &b);
} else {
a = b; // no warning
}
}
return a;
}
int compound_assign(int *arr, int n) {
int sum; // expected-note {{initialize}}
for (int i = 0; i < n; ++i)
sum += arr[i]; // expected-warning {{variable 'sum' is uninitialized}}
return sum / n;
}
int compound_assign_2(void) {
int x; // expected-note {{initialize}}
return x += 1; // expected-warning {{variable 'x' is uninitialized}}
}
int compound_assign_3(void) {
int x; // expected-note {{initialize}}
x *= 0; // expected-warning {{variable 'x' is uninitialized}}
return x;
}
int self_init_in_cond(int *p) {
int n = ((p && (0 || 1)) && (n = *p)) ? n : -1; // ok
return n;
}
void test_analyzer_noreturn_aux(void) __attribute__((analyzer_noreturn));
void test_analyzer_noreturn(int y) {
int x; // expected-note {{initialize the variable 'x' to silence this warning}}
if (y) {
test_analyzer_noreturn_aux();
++x; // no-warning
}
else {
++x; // expected-warning {{variable 'x' is uninitialized when used here}}
}
}
void test_analyzer_noreturn_2(int y) {
int x;
if (y) {
test_analyzer_noreturn_aux();
}
else {
x = 1;
}
++x; // no-warning
}
// Do not diagnose (functionally) empty structures as being uninitalized
// variables; see GH26842
struct empty {};
struct full_of_empty {
int : 0;
int : 12;
struct empty e;
};
struct empty empty_test_1(void) {
struct empty e;
return e; // no-warning
}
struct full_of_empty empty_test_2(void) {
struct full_of_empty e;
return e; // no-warning
}
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