Debug local stack frame variables fails - Failed to get module 'Builtin' from AST context

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21

It happened in a big project that I can not share. Are there any clues what I should check in the project?

22

We found the reason and the reason is this bug

23

Was this bug resolved?

I just upgraded to the 5.1 toolchain and the debugger seems busted. To absolve may own code I downloaded the Playing Cards example. It builds without incident, and I can run

$ .build/debug/Dealer

But using the debugger leads to this sequence:

$ lldb .build/debug/Dealer
(lldb) break set -l 18
(lldb) process launch
Target 0: (Dealer) stopped.
(lldb) n
Process 8390 stopped

  • thread #1, name = 'Dealer', stop reason = step over
    frame #0: 0x0000555555557aa2 Dealer`main at main.swift:20:17
    17
    18 let numberOfCards = 10
    19
    -> 20 var deck = Deck.standard52CardDeck()
    (lldb) po numberOfCards
    error: warning: failed to get module "Dealer" from AST context

I am running Ubuntu 18.04.1, and have swift and lldb referenced from same toolchain:
$ which swift
/home/microway/swift-5.1-RELEASE-ubuntu18.04/usr/bin/swift
$ which lldb
/home/microway/swift-5.1-RELEASE-ubuntu18.04/usr/bin/lldb

Any advice appreciated,
Randy

24

Were you using SwiftPM to build the Dealer executable? If yes, then you most likely ran into [SR-11008] lldb debug error when compiling project with SPM on Ubuntu 16.04 · Issue #4857 · apple/swift-package-manager · GitHub.

25

Yes, I was using the package manager.

Despite many efforts with Google search I never landed on the specific report you show - I will follow your example and do it 'manually' .

Thanks!

26

Actually Adrian, the brief example in that thread provides no idea of how to link my executables with the libraries I made. The line

$ swiftc -g -c a.swift ...

does not create a module without -emit-module, and when I try the final step with the linker it barfs out a long string of errors.

I have relied on either Xcode or SPM to manage builds, is there any documentation or examples to build a project (that includes dependencies) that shows how to build things with a conventional Make file?

Thanks!

27

You should be able to just look at what Xcode is doing and then mimic the steps shown in the build log. I'm also hearing that @Aciid is working on adding swiftpm support for this.

28

I landed the SwiftPM fixes today: [Build] Fix debugging for products built by SwiftPM by aciidb0mb3r · Pull Request #2348 · apple/swift-package-manager · GitHub

It should be in a trunk snapshot soon so you can use that when it comes out.

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