error: type for self cannot be reconstructed: type for typename

Encountering the same issue on Sonoma 14.6.1 (23G93) and Xcode 16.0 (16A242d). Seems this one is more like Xcode-related. As for me it sometimes get fixed after navigating through code using "steps" (step over/step into, etc.) and attempting to print object one more time, even after such error.

Report after running swift-healthcheck in lldb contains such errors like:

SwiftASTContextForExpressions(module: "ModuleName", cu: "MyFile.swift")::MyMethod() -- Missing Swift module or Clang module found for "ModuleName", "imported" via SwiftDWARFImporterDelegate. Hint: Register Swift modules with the linker using -add_ast_path.

Seems like suggested hint could solve the problem, but before upgrading to new Xcode I didn't have such issue.

same problem

Xcode Version 16.0 (16A242d)

Mac 15.0.1 (24A348)

Report after running swift-healthcheck in lldb contains such errors like:

Correct.

I also have report like you after swift-healthcheck:

SwiftASTContextForExpressions(module: "moduleName", cu: "MySwiftName.swift")::LoadOneModule() -- Missing Swift module or Clang module found for "moduleName", "imported" via SwiftDWARFImporterDelegate. Hint: Register Swift modules with the linker using -add_ast_path.

My Xcode project works fine in before i upgraded my macOS and Xcode. Actually i didn't do anything after i upgraded to macOS v15.0.1(24A348), Xcode 16.0(16A242d) except fix compilation problem.

There is a possibly solution for this issue（just like you sard, the hint）, but it did't work for me actually and i still try to figure it out. I wonder how could you solve the problem specifically.

Thanks.

Same. macOS: Sonoma 14.6.1, Xcode: 16.0 16A242d

I’m curious about the build systems everyone is using in this thread. We use a custom build system with remotely built static frameworks. I'm starting to encounter the same issue since Xcode 16.

-add_ast_path didn't help.

I also have a lot of logs like this when app becomes paused by lldb:

/Users/egormerkushev/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/23S4HX6OW8E8S/MyModule-2XYB5G9W7D2Z.pcm is out-of-date (hash mismatch). Type information from this module may be incomplete or inconsistent with the rest of the program. Rebuilding the project will regenerate the needed module files.

When I try print something I get it:

(lldb) po self
0x000000015d9de300
(lldb) po self.dismissGestureRecognizer
error: type for self cannot be reconstructed: type for typename "$s5MyModule31FullscreenContentViewControllerCD" was not found (cached)
error: Couldn't realize Swift AST type of self. Hint: using `v` to directly inspect variables and fields may still work.

Same problem with Xcode 16.0, everything was ok with Xcode 15.4. Not find work around yet

Same problem, XCode 16.0, MacBook M1 Pro

Same problem, Xcode 16.0 (16A242d), MacOS 15.0.1 (24A348)

Same problem, Xcode 16.1, MacOS 15.0

Same issue Xcode 16.1 and in Xcode 16.2.0-Beta.3 too

Same problem, Xcode 16.1 (16B40), MacOS 15.1.1 (24B91)

How many bugs does Xcode should have?

Apple: YESSSSSS