dispatch-once.m
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// RUN: %clang_analyze_cc1 -w -fblocks -verify %s \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=osx.API \
// RUN: -analyzer-checker=unix.Malloc \
// RUN: -analyzer-config display-checker-name=false
// RUN: %clang_analyze_cc1 -w -fblocks -fobjc-arc -verify %s \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=osx.API \
// RUN: -analyzer-checker=unix.Malloc \
// RUN: -analyzer-config display-checker-name=false
#include "Inputs/system-header-simulator-objc.h"
typedef unsigned long size_t;
void *calloc(size_t nmemb, size_t size);
typedef void (^dispatch_block_t)(void);
typedef long dispatch_once_t;
void dispatch_once(dispatch_once_t *predicate, dispatch_block_t block);
void test_stack() {
dispatch_once_t once;
dispatch_once(&once, ^{}); // expected-warning{{Call to 'dispatch_once' uses the local variable 'once' for the predicate value. Using such transient memory for the predicate is potentially dangerous. Perhaps you intended to declare the variable as 'static'?}}
}
void test_static_local() {
static dispatch_once_t once;
dispatch_once(&once, ^{}); // no-warning
}
void test_heap_var() {
dispatch_once_t *once = calloc(1, sizeof(dispatch_once_t));
// Use regexps to check that we're NOT suggesting to make this static.
dispatch_once(once, ^{}); // expected-warning-re{{{{^Call to 'dispatch_once' uses heap-allocated memory for the predicate value. Using such transient memory for the predicate is potentially dangerous$}}}}
}
void test_external_pointer(dispatch_once_t *once) {
// External pointer does not necessarily point to the heap.
dispatch_once(once, ^{}); // no-warning
}
typedef struct {
dispatch_once_t once;
} Struct;
void test_local_struct() {
Struct s;
dispatch_once(&s.once, ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the local variable 's' for the predicate value.}}
}
void test_heap_struct() {
Struct *s = calloc(1, sizeof(Struct));
dispatch_once(&s->once, ^{}); // expected-warning{{Call to 'dispatch_once' uses heap-allocated memory for the predicate value.}}
}
@interface Object : NSObject {
@public
dispatch_once_t once;
Struct s;
dispatch_once_t once_array[2];
}
- (void)test_ivar_from_inside;
- (void)test_ivar_struct_from_inside;
@end
@implementation Object
- (void)test_ivar_from_inside {
dispatch_once(&once, ^{}); // expected-warning{{Call to 'dispatch_once' uses the instance variable 'once' for the predicate value.}}
}
- (void)test_ivar_struct_from_inside {
dispatch_once(&s.once, ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the instance variable 's' for the predicate value.}}
}
- (void)test_ivar_array_from_inside {
dispatch_once(&once_array[1], ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the instance variable 'once_array' for the predicate value.}}
}
@end
void test_ivar_from_alloc_init() {
Object *o = [[Object alloc] init];
dispatch_once(&o->once, ^{}); // expected-warning{{Call to 'dispatch_once' uses the instance variable 'once' for the predicate value.}}
}
void test_ivar_struct_from_alloc_init() {
Object *o = [[Object alloc] init];
dispatch_once(&o->s.once, ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the instance variable 's' for the predicate value.}}
}
void test_ivar_array_from_alloc_init() {
Object *o = [[Object alloc] init];
dispatch_once(&o->once_array[1], ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the instance variable 'once_array' for the predicate value.}}
}
void test_ivar_from_external_obj(Object *o) {
// ObjC object pointer always points to the heap.
dispatch_once(&o->once, ^{}); // expected-warning{{Call to 'dispatch_once' uses the instance variable 'once' for the predicate value.}}
}
void test_ivar_struct_from_external_obj(Object *o) {
dispatch_once(&o->s.once, ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the instance variable 's' for the predicate value.}}
}
void test_ivar_array_from_external_obj(Object *o) {
dispatch_once(&o->once_array[1], ^{}); // expected-warning{{Call to 'dispatch_once' uses memory within the instance variable 'once_array' for the predicate value.}}
}
void test_block_var_from_block() {
__block dispatch_once_t once;
^{
dispatch_once(&once, ^{}); // expected-warning{{Call to 'dispatch_once' uses the block variable 'once' for the predicate value.}}
};
}
void use_block_var(dispatch_once_t *once);
void test_block_var_from_outside_block() {
__block dispatch_once_t once;
^{
use_block_var(&once);
};
dispatch_once(&once, ^{}); // expected-warning{{Call to 'dispatch_once' uses the block variable 'once' for the predicate value.}}
}
void test_static_var_from_outside_block() {
static dispatch_once_t once;
^{
dispatch_once(&once, ^{}); // no-warning
};
}