Runtime crash in property wrapper init

[AdamCmiel]

Description

Also found when investigating #85441:

When initializing a struct with a property wrapper PW of type C where C is a swift class with generic parameter T where T is constrained by objc protocol P but not meeting the PW's generic constraint, we get a crash in the getTypeContextDescriptor rather than a type-checking error.

Reproduction

// -- executable
// main.swift
import Wrapper

class CFromSwift<Param: Constraint>: @unchecked Sendable {}

struct WithObjCGenerics {
    @Wrapper private var wrappedProperty: CFromSwift<SomeModel>? = nil
}

let wog = WithObjCGenerics()

// main-bridging-header.h
#import "interface.h"

// interface.h
#import <Foundation/Foundation.h>
#import <ModelAndConstraint/ModelAndConstraint.h>

NS_ASSUME_NONNULL_BEGIN

@protocol SomeInterface <Constraint>
@end

typedef Model<SomeInterface> *SomeModel;

NS_ASSUME_NONNULL_END

// lib wrapper
// wrapper.swift
@propertyWrapper
public struct Wrapper<Value: Sendable>: Sendable {
    private let value: Value

    public init(wrappedValue valueProvider: @Sendable @escaping @autoclosure () -> Value) {
        self.value = valueProvider()
    }
    
    public var wrappedValue: Value {
        get { value }
    }
}

// lib modelAndConstraint
// ModelAndConstraint.h
#import <Foundation/Foundation.h>

@protocol Constraint
@end

NS_SWIFT_SENDABLE
@interface Model: NSObject
@end

// ModelAndConstraint.m
@implementation Model
@end

executable depends on libWrapper, libModelAndConstraint

Stack dump

* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff8)
    frame #0: 0x0000000100001590 StructGenericsCrash`Wrapper.init(valueProvider=0x0000000000000000) at <stdin>:0
    frame #1: 0x0000000100000e14 StructGenericsCrash`property wrapper backing initializer of WithObjCGenerics.wrappedProperty() at main.swift:0
    frame #2: 0x0000000100000c80 StructGenericsCrash`StructGenericsCrash.WithObjCGenerics.init() -> StructGenericsCrash.WithObjCGenerics at main.swift:0
  * frame #3: 0x0000000100000c44 StructGenericsCrash`main at main.swift:19:11
    frame #4: 0x000000018319eb98 dyld`start + 6076

Expected behavior

Either a type-checking error for the property wrapper or no crash at runtime

Environment

Xcode Version 26.0 (17A324)

Additional information

swapping SomeModel in main.swift for any SomeInterface will no longer crash