** Description changed:

+ [ Impact ]
+ 
+ * User can't use clang++-18 to build C++ code with -flto option.
+ 
+ [ Test Plan ]
+ 
+ * Install clang-18 from proposed updates.
+ * Try to build a C++ program with LTO (for example following the steps in 
original description.
+ 
+ [ Where problems could occur ]
+ 
+ * The missing LLVMgold.so is caused by switching to use mold in package
+ building. Using mold is introduced in llvm 18. The fix is just to revert
+ the change, and uses the same linker (gold) as old llvm versions. So the
+ change looks safe.
+ 
+ [ Other Info ]
+ 
+ * No
+ 
+ 
+ [Original Description]
+ 
+ 
  Unlike all other llvm-*-linker-tools packages, this one does not install 
`/usr/lib/llvm-18/lib/LLVMgold.so`. It does however install a broken symlink to 
it at `/usr/lib/bfd-plugins/LLVMgold-18.so`
  This results in compilation failures with clang++ when used with the `-flto` 
flag for link time optimization.
  
  To reproduce:
  
  main.cpp:
  ```c++
  int main() { return 0; }
  ```
  
  ```bash
  clang++ -flto main.cpp -o main
  ```
  
  Results in:
  ```
  /usr/bin/ld: /usr/lib/llvm-18/bin/../lib/LLVMgold.so: error loading plugin: 
/usr/lib/llvm-18/bin/../lib/LLVMgold.so: cannot open shared object file: No 
such file or directory
  clang++: error: linker command failed with exit code 1 (use -v to see 
invocation)
  ```
  
  Package version is
  
  llvm-18-linker-tools/noble,now 1:18.1.3-1 amd64
  
  llvm-18-linker-tools:
-   Installed: 1:18.1.3-1
-   Candidate: 1:18.1.3-1
-   Version table:
-  *** 1:18.1.3-1 500
-         500 http://de.archive.ubuntu.com/ubuntu noble/universe amd64 Packages
-         100 /var/lib/dpkg/status
+   Installed: 1:18.1.3-1
+   Candidate: 1:18.1.3-1
+   Version table:
+  *** 1:18.1.3-1 500
+         500 http://de.archive.ubuntu.com/ubuntu noble/universe amd64 Packages
+         100 /var/lib/dpkg/status

** Merge proposal linked:
   
https://code.launchpad.net/~zhsj/ubuntu/+source/llvm-toolchain-18/+git/llvm-toolchain-18/+merge/466494

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2064187

Title:
  llvm-18-linker-tools does not include LLVMgold.so

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