iOS TestFlight 设备上的 SIGSEGV 崩溃答案

【问题标题】：SIGSEGV Crash on iOS TestFlight DeviceiOS TestFlight 设备上的 SIGSEGV 崩溃
【发布时间】：2012-08-30 02:48:32
【问题描述】：

我有一个奇怪的崩溃，它只发生在 TestFlight ad hoc 发行版上。我知道导致崩溃的原因（一个简单的 while 循环，见下文），但我不明白为什么它不会在我的模拟器、iPhone 或 iPad（带有开发配置文件）上崩溃。

我一直在分发临时构建以跟踪崩溃，但我最终放弃了。如何更有效地跟踪此错误？

这是 TestFlight 崩溃报告：

    Exception reason

SIGSEGV

Stacktrace

PRIMARY THREAD THREAD 0

0 Meernotes 0x0019649a testflight_backtrace + 158
1 Meernotes 0x001970c4 TFSignalHandler + 244
2 libsystem_c.dylib 0x32d9d7ec _sigtramp + 48
3 libobjc.A.dylib 0x37d34eac _ZN12_GLOBAL__N_119AutoreleasePoolPage3popEPv + 224
4 libobjc.A.dylib 0x37d34eac _ZN12_GLOBAL__N_119AutoreleasePoolPage3popEPv + 224
5 libobjc.A.dylib 0x37d34dc8 _objc_autoreleasePoolPop + 12
6 CoreFoundation 0x358e1cfe _CFAutoreleasePoolPop + 18
7 UIKit 0x333d5c92 _wrapRunLoopWithAutoreleasePoolHandler + 42
8 CoreFoundation 0x35965b1a __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 18
9 CoreFoundation 0x35963d56 __CFRunLoopDoObservers + 258
10 CoreFoundation 0x359640b0 __CFRunLoopRun + 760
11 CoreFoundation 0x358e74a4 CFRunLoopRunSpecific + 300
12 CoreFoundation 0x358e736c CFRunLoopRunInMode + 104
13 GraphicsServices 0x37583438 GSEventRunModal + 136
14 UIKit 0x333f3cd4 UIApplicationMain + 1080
15 Meernotes 0x000850da main (main.m:16)
16 Meernotes 0x0008508f start + 39

这是触发它的代码（但在模拟器/iphone上很好）：

        while (textStillFits) {

        textToBeKeptBeforeCutting = textToBeKept;
        textToBeMovedBeforeCutting = textToBeMoved;

        rangeCutOffPosition = [settings determineFirstCutOffRangeOfString:textToBeMoved];
        textToBeKeptTemp = [textToBeMoved substringToIndex:rangeCutOffPosition.location];
        textToBeMovedTemp = [textToBeMoved substringFromIndex:rangeCutOffPosition.location];
        textToBeMoved = textToBeMovedTemp;
        textToBeKept = [NSString stringWithFormat:@"%@%@", textToBeKept, textToBeKeptTemp];
        NSUInteger l = [settings linesOfText:textToBeKept];
        if (l > maxLines) {
            textStillFits = NO;
            textToBeKept = textToBeKeptBeforeCutting;
            textToBeMoved = textToBeMovedBeforeCutting;
            // brakes here!
        }else {
            textStillFits = YES;
        }
    }

我看过这个，但没有帮助：ad hoc iphone sigsegv crash

更多上下文，正如@ott 提到的 NSNotFound 可能会导致：

    -(NSRange)determineFirstCutOffRangeOfString:(NSString *)s {

    NSRange rangeSpace = [s rangeOfString:@" " options:NSCaseInsensitiveSearch];
    NSRange rangeReturn = [s rangeOfString:@"\n" options:NSCaseInsensitiveSearch];
    if (rangeSpace.location == NSNotFound && rangeReturn.location == NSNotFound) {
        rangeSpace = NSMakeRange(1, 0); // don't take 0,0 as this will lead to endless loop
        rangeReturn = NSMakeRange(1, 0);
        NSLog(@"NEITHER SPACE NOR RETURN FOUND");
    }

    NSRange rangeCutOffPosition = NSMakeRange(0, 0);
    if (rangeSpace.location < rangeReturn.location) {
        // i.e. if the space char is the lowest char where you can cut off
        rangeCutOffPosition = NSMakeRange(rangeSpace.location+1,0); // +1, i.e. always cut off AFTER the space
    }  else {
        // i.e. if the return char is the lowest char where you can cut off
        rangeCutOffPosition = NSMakeRange(rangeReturn.location+1,0); // +1, i.e. always cut off AFTER the return
    }

    return rangeCutOffPosition;
}

【问题讨论】：

会不会是rangeCutOffPosition 变成了NotFound 之类的东西？该设备通常在模拟器忽略它的情况下更加挑剔。你能插入一些 NSLog() 来看看发生了什么，或者通过它。
@ott 我总是初始化 NSRange rangeCutOffPosition = NSMakeRange(0, 0);所以它不能是 NSNotFound。但是，在此之前我有一些方法可以检查其他范围，这可能会返回 NSNotFound。但这怎么会是个问题呢？
@ott 我在上面提供了更多代码上下文。感谢您的帮助！
这是使用 ARC 还是手动引用计数？

标签： iphone ios segmentation-fault ad-hoc-distribution testflight

【解决方案1】：

他们最新的sdk 1.2.4 解决了这个问题！

【讨论】：