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// RUN: %clang_analyze_cc1 -triple x86_64-apple-darwin10 -analyzer-checker=core,alpha.core.StackAddressAsyncEscape -fblocks -fobjc-arc -verify %s
typedef struct dispatch_queue_s *dispatch_queue_t;
typedef void (^dispatch_block_t)(void);
void dispatch_async(dispatch_queue_t queue, dispatch_block_t block);
typedef long dispatch_once_t;
void dispatch_once(dispatch_once_t *predicate, dispatch_block_t block);
typedef long dispatch_time_t;
void dispatch_after(dispatch_time_t when, dispatch_queue_t queue, dispatch_block_t block);
void dispatch_barrier_sync(dispatch_queue_t queue, dispatch_block_t block);
extern dispatch_queue_t queue;
extern dispatch_once_t *predicate;
extern dispatch_time_t when;
void test_block_expr_async() {
int x = 123;
int *p = &x;
dispatch_async(queue, ^{
*p = 321;
});
// expected-warning@-3 {{Address of stack memory associated with local variable 'x' \
is captured by an asynchronously-executed block}}
}
void test_block_expr_once_no_leak() {
int x = 123;
int *p = &x;
// synchronous, no warning
dispatch_once(predicate, ^{
*p = 321;
});
}
void test_block_expr_after() {
int x = 123;
int *p = &x;
dispatch_after(when, queue, ^{
*p = 321;
});
// expected-warning@-3 {{Address of stack memory associated with local variable 'x' \
is captured by an asynchronously-executed block}}
}
void test_block_expr_async_no_leak() {
int x = 123;
int *p = &x;
// no leak
dispatch_async(queue, ^{
int y = x;
++y;
});
}
void test_block_var_async() {
int x = 123;
int *p = &x;
void (^b)(void) = ^void(void) {
*p = 1;
};
dispatch_async(queue, b);
// expected-warning@-1 {{Address of stack memory associated with local variable 'x' \
is captured by an asynchronously-executed block}}
}
void test_block_with_ref_async() {
int x = 123;
int &r = x;
void (^b)(void) = ^void(void) {
r = 1;
};
dispatch_async(queue, b);
// expected-warning@-1 {{Address of stack memory associated with local variable 'x' \
is captured by an asynchronously-executed block}}
}
dispatch_block_t get_leaking_block() {
int leaked_x = 791;
int *p = &leaked_x;
return ^void(void) {
*p = 1;
};
// expected-warning@-3 {{Address of stack memory associated with local variable 'leaked_x' \
is captured by a returned block}}
}
void test_returned_from_func_block_async() {
dispatch_async(queue, get_leaking_block());
// expected-warning@-1 {{Address of stack memory associated with local variable 'leaked_x' \
is captured by an asynchronously-executed block}}
}
// synchronous, no leak
void test_block_var_once() {
int x = 123;
int *p = &x;
void (^b)(void) = ^void(void) {
*p = 1;
};
dispatch_once(predicate, b); // no-warning
}
void test_block_var_after() {
int x = 123;
int *p = &x;
void (^b)(void) = ^void(void) {
*p = 1;
};
dispatch_after(when, queue, b);
// expected-warning@-1 {{Address of stack memory associated with local variable 'x' \
is captured by an asynchronously-executed block}}
}
void test_block_var_async_no_leak() {
int x = 123;
int *p = &x;
void (^b)(void) = ^void(void) {
int y = x;
++y;
};
dispatch_async(queue, b); // no-warning
}
void test_block_inside_block_async_no_leak() {
int x = 123;
int *p = &x;
void (^inner)(void) = ^void(void) {
int y = x;
++y;
};
void (^outer)(void) = ^void(void) {
int z = x;
++z;
inner();
};
dispatch_async(queue, outer); // no-warning
}
dispatch_block_t accept_and_pass_back_block(dispatch_block_t block) {
block();
return block; // no-warning
}
void test_passing_continuation_no_leak() {
int x = 123;
int *p = &x;
void (^cont)(void) = ^void(void) {
*p = 128;
};
accept_and_pass_back_block(cont); // no-warning
}
@interface NSObject
@end
@protocol OS_dispatch_semaphore
@end
typedef NSObject<OS_dispatch_semaphore> *dispatch_semaphore_t;
dispatch_semaphore_t dispatch_semaphore_create(long value);
long dispatch_semaphore_wait(dispatch_semaphore_t dsema, dispatch_time_t timeout);
long dispatch_semaphore_signal(dispatch_semaphore_t dsema);
void test_no_leaks_on_semaphore_pattern() {
int x = 0;
int *p = &x;
dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);
dispatch_async(queue, ^{
*p = 1;
// Some work.
dispatch_semaphore_signal(semaphore);
}); // no-warning
// Do some other work concurrently with the asynchronous work
// Wait for the asynchronous work to finish
dispatch_semaphore_wait(semaphore, 1000);
}
void test_dispatch_barrier_sync() {
int buf[16];
for (int n = 0; n < 16; ++n) {
int *ptr = &buf[n];
// FIXME: Should not warn. The dispatch_barrier_sync() call ensures
// that the block does not outlive 'buf'.
dispatch_async(queue, ^{ // expected-warning{{Address of stack memory associated with local variable 'buf' is captured by an asynchronously-executed block}}
(void)ptr;
});
}
dispatch_barrier_sync(queue, ^{});
}
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