Symbol not found crashed

[swlfigo]

My Swift Project , after I add -Xlinker and -interposable flag in other linker flag , it crashed at the beginning when i run the Simulator.If not add these flag , injection worked fine exact hot reload extension swift class.
It Shows Message In Console:

dyld[7480]: Symbol not found: _$s3lhb10UrlConfingCfE
  Referenced from: <AB1B2512-64EA-3D96-BD7E-577FA1A00BDA> /Users/hi/Library/Developer/CoreSimulator/Devices/ABC6A0EF-3361-49A2-92B5-E19C13C3877F/data/Containers/Bundle/Application/0D7E6C26-F0C5-47E0-A7F7-247BEDA4A165/hi.app/hi
  Expected in:     <AB1B2512-64EA-3D96-BD7E-577FA1A00BDA> /Users/hi/Library/Developer/CoreSimulator/Devices/ABC6A0EF-3361-49A2-92B5-E19C13C3877F/data/Containers/Bundle/Application/0D7E6C26-F0C5-47E0-A7F7-247BEDA4A165/hi.app/hi

XCode Version: Version 16.4 (16F6)
MacOS Version: 15.5 (24F74)

I have read this Issues: issues535
I tried add dummy function like this , it also crash:

[swlfigo]

Also try Set ENABLE_DEBUG_DYLIB = NO; , Not worked

[johnno1962]

HI, thanks for researching and trying the dummy symbol approach. Looks like you have an extra space in your symbol name though.

[swlfigo]

HI, thanks for researching and trying the dummy symbol approach. Looks like you have an extra space in your symbol name though.

@johnno1962 Yes, I have tried delete extra space , unfortunately same problem

[johnno1962]

can you try public fund dummy()?

[swlfigo]

can you try public fund dummy()?

Same Problem. I change my machine and run the project, will get another symbol not found

dyld[18592]: Symbol not found: _$s3lhb10PhotoErrorOwug

Here is my code

[johnno1962]

Yeah, when using -interposable, it seems there are sometimes random problems with dynamic loading. I recommend you try adding another "Other Linker Flags": -fuse-ld=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld-classic to switch back to the previous version of the linker.

[swlfigo]

Yeah, when using -interposable, it seems there are sometimes random problems with dynamic loading. I recommend you try adding another "Other Linker Flags": -fuse-ld=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld-classic to switch back to the previous version of the linker.

Wow! This flag solve the crash problem and can use hot reload when i modify code in extension class in my previous machine ! will check this flag later in another machine!
If add this flag, no longer and @_cdecl ("xxx") code snippets.
So, whats the problem will cause these crashes?(BTW: Before I use Xcode.app , then I use Xcodes.app to install multiple xcodes, but different xcodes app also crash before)

[johnno1962]

It's a bug in the linker when you use -interrposing. I've filed a radar already and I'll add this issue to it. The flag just switches which linker version clang uses. If you're up and running don't forget to close this issue.

[swlfigo]

Update:
By Adding "Other Linker Flags": -fuse-ld=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld-classic , Symbol not found crashed Fixed and Injection worked fine

[mikewuu]

Thank you! This was the fix for me as well (missing rust symbol in Convex Mobile)

[johnno1962]

@mikewuu, which version of Xcode are you using?

[mikewuu]

26.4.1

dyld[91685]: Symbol not found: __ZN41_$LT$T$u20$as$u20$serde..de..Expected$GT$3fmt17h90dea608d5b9ff89E

Rust/Serde symbol

[johnno1962]

Thanks, that's definitely a current version of Xcode and I checked with https://github.com/strangeliu/InterposableLinkIssue and it still seems to be an issue with Xcode 26.5 so I have filed a radar FB22853074 if you want to back it up.