Introduction: I’m encountering a consistent crash in production on iOS 26.2 (build 23C55). The crash occurs deep within libicucore when calling [NSDateFormatter dateFromString:]. Crash Summary: Exception Type: SIGSEGV (SEGV_ACCERR) Fault Address: 0xffffffff Thread: Crashed on Main Thread (Thread 0) Library: libicucore.A.dylib Code Snippet: The crash is triggered by the following method. It converts a string to an NSDate using a specific format and locale: // 获取日期date - (NSDate *)getDateWithTime:(NSString *)time formatter:(NSString *)formatterStr { NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:formatterStr]; formatter.timeZone = [NSTimeZone timeZoneWithName:@"Asia/Shanghai"]; formatter.locale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"]; return [formatter dateFromString:time]; } Backtrace: Here is the relevant part of the crash report: Incident Identifier: E24485B6-C53E-4115-A6CF-A7E4A952AD50 CrashReporter Key: 21FAC1CF-F56B-409A-98AA-351D3D2EB06C Hardware Model: iPhone18,2 Code Type: ARM-64 Parent Process: [1] Date/Time: 2026-01-12T01:32:25Z OS Version: iPhone OS 26.2 (23C55) Report Version: 105 SDK Version: 0.0.4 Exception Type: SIGSEGV Exception Codes: SEGV_ACCERR at 0xffffffff Crashed Thread: 0 Thread 0 Crashed: 0 libicucore.A.dylib 0x000000019b81def8 0x19b74a000 + 868088 1 libicucore.A.dylib 0x000000019b7da91c 0x19b74a000 + 592156 2 libicucore.A.dylib 0x000000019b8d8340 0x19b74a000 + 1631040 3 libicucore.A.dylib 0x000000019b8eae18 0x19b74a000 + 1707544 4 libicucore.A.dylib 0x000000019b8eb600 0x19b74a000 + 1709568 5 libicucore.A.dylib 0x000000019b878be4 0x19b74a000 + 1240036 6 libicucore.A.dylib 0x000000019b87ae84 0x19b74a000 + 1248900 7 libicucore.A.dylib 0x000000019b87b2dc 0x19b74a000 + 1250012 8 libicucore.A.dylib 0x000000019b9564ac 0x19b74a000 + 2147500 9 libicucore.A.dylib 0x000000019b954afc 0x19b74a000 + 2140924 10 libicucore.A.dylib 0x000000019b952794 0x19b74a000 + 2131860 11 libicucore.A.dylib 0x000000019b98689c 0x19b74a000 + 2345116 12 CoreFoundation 0x00000001895dbfe0 0x18953d000 + 651232 13 CoreFoundation 0x00000001895dbaa0 0x18953d000 + 649888 14 Foundation 0x0000000186d2029c 0x186b88000 + 1671836 15 Foundation 0x00000001874a62dc 0x186b88000 + 9560796 16 Foundation 0x00000001874a6384 0x186b88000 + 9560964 17 xxxx 0x0000000105ea6e30 -[xxxxx getDateWithTime:formatter:] + 168 and Thread 0 crashed with ARM-64 Thread State: pc: 0x000000019b81def8 fp: 0x000000016f96bc10 sp: 0x000000016f96bbd0 x0: 0x00000000ffffffff x1: 0x000000019ba1e8e0 x2: 0x0000000000000002 x3: 0x000000000000000b x4: 0x0000000000000074 x5: 0x0000000000000069 x6: 0x0000000000000000 x7: 0xfffff0003ffff800 x8: 0x000000009ba18014 x9: 0x00000001148dffd0 x10: 0x0000000000000002 x11: 0x0000000000000004 x12: 0x0000000000000220 x13: 0x0000000000000030 x14: 0x000000015b6f36b8 x15: 0x000000015cfe0000 x16: 0x00000002a19d0ff0 x17: 0x00000001f5590a70 x18: 0x0000000000000000 x19: 0x000000016f96bc30 x20: 0x0000000000000000 x21: 0x000000015cfe3200 x22: 0x000000019ba18014 x23: 0x0000000000000000 x24: 0x000000015cfe32a0 x25: 0x0000000000000003 x26: 0x0000000000000000 x27: 0x0000000000000000 x28: 0x000000015cfe3200 lr: 0x000000019b7da958 cpsr: 0x00000000a0000000

I encountered a crash when calling the tabBarView:didSelectIndex: method, and it only happens on iOS 18. Here is crash report: `OS Version: iPhone OS 18.0.1 (22A3370) Report Version: 105 SDK Version: 0.0.4 Exception Type: SIGABRT Exception Codes: #0 at 0x1f0acb274 Crashed Thread: 0 Application Specific Information: *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Layout requested for visible navigation bar, <UINavigationBar: 0x11266ef80; frame = (0 -91; 428 44); autoresize = W; tintColor = UIExtendedSRGBColorSpace 1 1 1 0.8; layer = <CALayer: 0x301e14800>> delegate=0x112670600 standardAppearance=0x3035b3720 scrollEdgeAppearance=0x3035b3b10, when the top item belongs to a different navigation bar. topItem = <UINavigationItem: 0x14309cf00> title='' titleView=0x15b1af700 style=navigator leftBarButtonItems=0x301c08940 rightBarButtonItems=0x301caa180, navigation bar = <UINavigationBar: 0x11266e080; frame = (0 -91; 428 44); autoresize = W; tintColor = UIExtendedSRGBColorSpace 1 1 1 0.8; layer = <CALayer: 0x301e1d0a0>> delegate=0x112670000 standardAppearance=0x30355ae60 scrollEdgeAppearance=0x30355aed0, possibly from a client attempt to nest wrapped navigation controllers.' Last Exception Backtrace: 0 CoreFoundation 0x00000001a0cad08c 0x1a0c29000 + 540812 1 libobjc.A.dylib 0x000000019dfaf2e4 0x19df98000 + 94948 2 Foundation 0x00000001a007e15c 0x19f85c000 + 8528220 3 UIKitCore 0x00000001a36b6028 0x1a33f4000 + 2891816 4 UIKitCore 0x00000001a3404248 0x1a33f4000 + 66120 5 UIKitCore 0x00000001a354d878 0x1a33f4000 + 1415288 6 QuartzCore 0x00000001a2749630 0x1a26d1000 + 493104 7 UIKitCore 0x00000001a3447cd0 0x1a33f4000 + 343248 8 UIKitCore 0x00000001a34e9a60 0x1a33f4000 + 1006176 9 UIKitCore 0x00000001a354aa48 0x1a33f4000 + 1403464 10 UIKitCore 0x00000001a34f1c64 0x1a33f4000 + 1039460 11 UIKitCore 0x00000001a368e2c8 0x1a33f4000 + 2728648 12 UIKitCore 0x00000001a368c504 0x1a33f4000 + 2721028 13 UIKitCore 0x00000001a34193c8 0x1a33f4000 + 152520 14 UIKitCore 0x00000001a34191f4 0x1a33f4000 + 152052 15 UIKitCore 0x00000001a340ae84 0x1a33f4000 + 93828 16 CoreAutoLayout 0x00000001c3ad7030 0x1c3ac5000 + 73776 17 UIKitCore 0x00000001a340ddc8 0x1a33f4000 + 105928 18 UIKitCore 0x00000001a340c7f0 0x1a33f4000 + 100336 19 UIKitCore 0x00000001a378087c 0x1a33f4000 + 3721340 20 UIKitCore 0x00000001a37804f0 0x1a33f4000 + 3720432 21 UIKitCore 0x00000001a377e814 0x1a33f4000 + 3713044 22 UIKitCore 0x00000001a37ee8a4 0x1a33f4000 + 4171940 23 UIKitCore 0x00000001a37edf14 0x1a33f4000 + 4169492`

When I call the iconv function in the iOS 17.1 beta version to convert from GBK encoding to GBK encoding, character conversion is abnormal. However, in the same scenario, it works fine in iOS 17. Iconv is used extensively in our project. Can you please tell me what changes have been made in the latest version?