# Error running hello world using pixi shell in cursor

**URL:** <https://forum.modular.com/t/error-running-hello-world-using-pixi-shell-in-cursor/1918>\
**Category:** VS Code Extension\
**Created:** [July 7, 2025, 9:37am UTC](https://forum.modular.com/t/error-running-hello-world-using-pixi-shell-in-cursor/1918 "2025-07-07T09:37:48Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![cyrillzadra](https://avatars.discourse-cdn.com/v4/letter/c/46a35a/32.png) [@cyrillzadra](https://forum.modular.com/u/cyrillzadra)\
**Post date:** [July 7, 2025, 9:37am UTC](https://forum.modular.com/t/error-running-hello-world-using-pixi-shell-in-cursor/1918/1 "2025-07-07T09:37:48Z")

</div>

Hello .. I just installed Mojo with Pixi on my Windows system using WSL. I’m editing my Mojo code with Cursor + Mojo Vscode extension (nightly) and Remote Development (OpenSSH).

When I run a Mojo hello world program, it works without any issues.

 ![image](https://us1.discourse-cdn.com/flex001/uploads/modular/original/1X/7bf4fa516f1c1198b1a094a630c13a72bb16eb0e.png)

But as soon as I start a `pixi shell`, I get some unclear error messages to me 🙂

 ![image](https://us1.discourse-cdn.com/flex001/uploads/modular/original/1X/df9ce983cb5481798ad0ad91c1d4d6ecad914d89.png)

Running mojo in terminal works without error.

 ![image](https://us1.discourse-cdn.com/flex001/uploads/modular/original/1X/ad91bce507afe27b37fa255fd6960cd8f1c0c285.png)

Complete error

```auto
/home/cyrill/.cursor-server/data/User/globalStorage/modular-mojotools.vscode-mojo-nightly/magic-data-home/envs/max/bin/mojo run /home/cyrill/mojo-playground/mojo-playground/hello.🔥
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x1" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x2" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x2" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x5" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: unit
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x1" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"group`9" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: unit
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x6" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: unit
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"idx`7" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"idx`2x1" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x11" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x1" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x2" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`1" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`5" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`8" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`4" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x5" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"_`2x8" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x5" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`21" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x2" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x3" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`2x1" : !lit.struct<@stdlib::@builtin::@int::@Int>>
/home/cyrill/mojo-playground/.pixi/envs/default/lib/mojo/stdlib.mojopkg:0:0: error: expected mlir::TypedAttr, but got: #kgen<param.decl *"i`7" : !lit.struct<@stdlib::@builtin::@int::@Int>>
[430243:430243:20250707,112852.153754:ERROR elf_dynamic_array_reader.h:64] tag not found
[430243:430243:20250707,112852.158152:ERROR file_io_posix.cc:144] open /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq: No such file or directory (2)
[430243:430243:20250707,112852.158256:ERROR file_io_posix.cc:144] open /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq: No such file or directory (2)
Please submit a bug report to https://github.com/modular/modular/issues and include the crash backtrace along with all the relevant source codes.
Stack dump:
0. Program arguments: /home/cyrill/.cursor-server/data/User/globalStorage/modular-mojotools.vscode-mojo-nightly/magic-data-home/envs/max/bin/mojo run /home/cyrill/mojo-playground/mojo-playground/hello.\360\237\224\245
 #0 0x00005ef23b19e95b llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) Signals.cpp:0:0
 #1 0x00005ef23b19c72b llvm::sys::RunSignalHandlers() Signals.cpp:0:0
 #2 0x00005ef23b19f00a SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #3 0x00007726bb445330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
 #4 0x00007726bb49eb2c pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x9eb2c)
 #5 0x00007726bb44527e raise (/lib/x86_64-linux-gnu/libc.so.6+0x4527e)
 #6 0x00007726bd7b4142 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #7 0x00007726bb445330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
 #8 0x00005ef23893b92f void llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>::callback_fn<mlir::bytecode::detail::IRNumberingState::computeGlobalNumberingState(mlir::Operation*)::$_0>(long, mlir::Operation*, mlir::WalkStage const&) IRNumbering.cpp:0:0
 #9 0x00005ef23b11d65e mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#10 0x00005ef23b11d646 mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#11 0x00005ef23b11d646 mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#12 0x00005ef23b11d646 mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#13 0x00005ef23b11d646 mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#14 0x00005ef23b11d646 mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#15 0x00005ef23b11d646 mlir::detail::walk(mlir::Operation*, llvm::function_ref<void (mlir::Operation*, mlir::WalkStage const&)>) Visitors.cpp:0:0
#16 0x00005ef23892fcb2 mlir::bytecode::detail::IRNumberingState::IRNumberingState(mlir::Operation*, mlir::BytecodeWriterConfig const&) IRNumbering.cpp:0:0
#17 0x00005ef2389246f2 mlir::writeBytecodeToFile(mlir::Operation*, llvm::raw_ostream&, mlir::BytecodeWriterConfig const&) BytecodeWriter.cpp:0:0
#18 0x00005ef2381cdae0 M::Cache::cachedTransform(mlir::Operation*, M::RCRef<M::Cache::BlobCache<M::Cache::TransformCacheKey>>, M::AsyncRT::AnyAsyncValueRef, mlir::PassManager&, std::function<void (mlir::Operation*)> const&, std::function<void (mlir::Operation*)> const&) CachedTransform.cpp:0:0
#19 0x00005ef237ca5cd7 M::KGEN::KGENCompiler::runKGENPipeline(mlir::ModuleOp, M::TargetInfoAttr, M::RCRef<M::Cache::BlobCache<M::Cache::TransformCacheKey>>, M::AsyncRT::AnyAsyncValueRef, std::function<void (mlir::Operation*)>, std::function<void (mlir::Operation*)>) KGENCompiler.cpp:0:0
#20 0x00005ef237ca5514 M::KGEN::KGENCompiler::runKGENPipeline(mlir::ModuleOp, M::TargetInfoAttr) KGENCompiler.cpp:0:0
#21 0x00005ef237ad5b4a run(M::State const&) mojo-run.cpp:0:0
#22 0x00005ef237ae05f3 main mojo.cpp:0:0
#23 0x00007726bb42a1ca (/lib/x86_64-linux-gnu/libc.so.6+0x2a1ca)
#24 0x00007726bb42a28b __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2a28b)
#25 0x00005ef237ab2965 _start (/home/cyrill/.cursor-server/data/User/globalStorage/modular-mojotools.vscode-mojo-nightly/magic-data-home/envs/max/bin/mojo+0x271a965)
mojo crashed!
Please file a bug report.
Segmentation fault (core dumped)

```

thanks for help

---

<div class="post-metadata">

**Author:** ![Ehsan](https://sea1.discourse-cdn.com/flex001/user_avatar/forum.modular.com/ehsan/32/142_2.png) [@Ehsan](https://forum.modular.com/u/Ehsan)\
**Post date:** [July 7, 2025, 6:44pm UTC](https://forum.modular.com/t/error-running-hello-world-using-pixi-shell-in-cursor/1918/2 "2025-07-07T18:44:24Z")

</div>

Looks like shell has already been activated. An active shell has `(project name)` prepended to the line in terminal. To deactivate the shell simply run `exit`. Note that if you’re _not_ in a shell you’d need to have `pixi run mojo code.mojo` to run the code and with an activate shell, it’s as usual `mojo code.mojo`. Hope it’s clear now.