我在 arc4random 调用期间遇到了奇怪的崩溃，该调用仅在应用程序运行大约 4 分钟后才出现，而且并非每次都这样做。这是崩溃日志：
Incident Identifier: 25C8C57F-0434-40B2-A2E8-FE88F58ABF60
CrashReporter Key: 8683ce910e9db4ba69f61266b606396f941d08ee
Hardware Model: iPhone2,1
Version: ??? (???)
Code Type: ARM (Native)
Parent Process: launchd [1]
Date/Time: 2011-01-16 18:46:45.170 +0000
OS Version: iPhone OS 4.2.1 (8C148a)
Report Version: 104
Exception Type: 00000020
Exception Codes: 0x8badf00d
Highlighted Thread: 0
Application Specific Information:
<App> failed to resume in time
Elapsed total CPU time (seconds): 5.930 (user 5.380, system 0.550), 100% CPU
Elapsed application CPU time (seconds): 4.790, 81% CPU
Thread 0:
0 libSystem.B.dylib 0x31168006 pthread_mutex_lock + 50
1 libSystem.B.dylib 0x3118cb10 arc4random + 24
2 <App> 0x0000f658 -[BasicGameLayer updateBoard] (BasicGameScreen.mm:318)
3 <App> 0x00010790 -[BasicGameLayer handleTouches:withEvent:] (BasicGameScreen.mm:238)
4 <App> 0x0000e504 -[BasicGameLayer ccTouchesBegan:withEvent:] (BasicGameScreen.mm:276)
BasicGameScreen.mm 的第 318 行是一个左大括号。我假设编译器正在删除空格，所以我认为它崩溃的行是
int selection = arc4random() % 16;