Confirm, I experience the same crash on Xcode 13.2/13.2.1. Code inside of body if #available(iOS 15.0, *) { textField15 } else { textField // crash on iOS 14.7.1 } Stack Trace Date/Time: 2021-12-21 22:15:39.8220 -0600 Launch Time: 2021-12-21 22:02:37.5490 -0600 OS Version: iPhone OS 14.7.1 (18G82) Release Type: User Baseband Version: 1.80.02 Report Version: 104 Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000000 VM Region Info: 0 is not in any region. Bytes before following region: 4333060096 REGION TYPE START - END [ VSIZE] PRT/MAX SHRMOD REGION DETAIL UNUSED SPACE AT START ---> __TEXT 102454000-102458000 [ 16K] r-x/r-x SM=COW ...stop-appstore Termination Signal: Segmentation fault: 11 Termination Reason: Namespace SIGNAL, Code 0xb Terminating Process: exc handler [356] Triggered by Thread: 0 Thread 0 name: Thread 0 Crashed: 0 libswiftCore.dylib 0x00000001a6996750 swift::ResolveAsSymbolicReference::operator()(swift::Demangle::__runtime::SymbolicReferenceKind, swift::Demangle::__runtime::Directness, int, void const*) + 124 (MetadataValues.h:1263) 1 libswiftCore.dylib 0x00000001a69b8018 swift::Demangle::__runtime::Demangler::demangleSymbolicReference(unsigned char) + 212 (functional:1880) 2 libswiftCore.dylib 0x00000001a69b4d04 swift::Demangle::__runtime::Demangler::demangleType(__swift::__runtime::llvm::StringRef, std::__1::function<swift::Demangle::__runtime::Node* (swift::Demangle::__runtime::SymbolicReferenceKind, swi... + 200 (Demangler.cpp:589) 3 libswiftCore.dylib 0x00000001a699c660 swift_getTypeByMangledNameImpl(swift::MetadataRequest, __swift::__runtime::llvm::StringRef, void const* const*, std::__1::function<swift::TargetMetadata<swift::InProcess> const* (unsigned int, unsi... + 496 (MetadataLookup.cpp:69) 4 libswiftCore.dylib 0x00000001a6999ab0 swift::swift_getTypeByMangledName(swift::MetadataRequest, __swift::__runtime::llvm::StringRef, void const* const*, std::__1::function<swift::TargetMetadata<swift::InProcess> const* (unsigned int, u... + 604 (CompatibilityOverride.def:153) 5 libswiftCore.dylib 0x00000001a6999d08 swift_getTypeByMangledNameInContext + 152 (MetadataLookup.cpp:1735) 6 wingstop-appstore 0x000000010281bac8 __swift_instantiateConcreteTypeFromMangledName + 52 (<compiler-generated>:0) 7 wingstop-appstore 0x000000010283251c specialized HStack.init(alignment:spacing:content:) + 36 (<compiler-generated>:0)