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/*
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* Copyright (c) 2014 - present Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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*/
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#import <Foundation/Foundation.h>
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@interface A : NSObject
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@property(nonatomic) int x;
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+ (instancetype)sharedInstance;
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@end
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@implementation A {
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}
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+ (instancetype)sharedInstance {
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static dispatch_once_t once;
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static id sharedInstance;
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dispatch_once(&once, ^{
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sharedInstance = [[self alloc] init];
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});
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return sharedInstance;
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}
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+ (instancetype)trans {
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static id sharedInstance;
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void (^dummy_block)() = ^{
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sharedInstance = [[self alloc] init];
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};
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dummy_block();
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return sharedInstance;
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}
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+ (instancetype)dispatch_a_block_variable {
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static __typeof__([self new]) static_storage__;
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void (^initialization_block__)() = ^{
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static_storage__ = ([self new]);
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};
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static dispatch_once_t once_token__;
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_dispatch_once(&once_token__, initialization_block__);
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return static_storage__;
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}
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+ (instancetype)dispatch_a_block_variable_from_macro {
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return ({
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static __typeof__([self new]) static_storage__;
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void (^initialization_block__)() = ^{
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static_storage__ = ([self new]);
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};
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static dispatch_once_t once_token__;
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_dispatch_once(&once_token__, initialization_block__);
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static_storage__;
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});
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}
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+ (int)dispatch_a_block_variable_from_macro_delivers_initialised_object {
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A* a = [A dispatch_a_block_variable_from_macro];
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a->_x = 5;
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return 1 / (a->_x - 5);
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}
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@end
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int main() {
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A* b = [A sharedInstance];
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int* p = 0;
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if (b == 0)
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return *p;
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else
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return 0;
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}
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