[BUG] Windows fatal exception: access violation op _cpp_parse

[basberg]

• I have reviewed this project's contribution guidelines

Describe the bug
I get a "Windows fatal exception: access violation" error when i parse an RDL file.

I get the above error with the provided examples: print_hierarchy.py and tiny.rdl.
To get the logging shown above I need to run python with -X faulthandler, otherwise it closes silently: no logging.
I use Python 3.12.2 (also tried 3.14.0 and 3.12.0)

pip freeze:
antlr4-python3-runtime==4.13.2
colorama==0.4.6
Markdown==3.9
systemrdl-compiler==1.30.1
typing_extensions==4.15.0

The machine is Windows 11 Pro. I ran python via Powershell.

The weird thing is that i dont see this error on any of my other machines. Just this one.

Do you have an idea how i can debug this?

Expected behavior
I expect it to print the rdl hierarchy like the example does.

Additional context
Add any other context about the problem here.

[amykyta3]

Can you check if you have the MSVC runtime libraries installed? ( https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170#latest-microsoft-visual-c-redistributable-version ) Suspect this is the same issue as #249

…

On Wed, Oct 15, 2025, 4:19 AM basberg ***@***.***> wrote: *basberg* created an issue (SystemRDL/systemrdl-compiler#297) <#297> - I have reviewed this project's contribution guidelines <https://github.com/SystemRDL/systemrdl-compiler/blob/main/CONTRIBUTING.md> *Describe the bug* I get a "Windows fatal exception: access violation" error when i parse an RDL file. image.png (view on web) <https://github.com/user-attachments/assets/aa09edf3-525d-42a3-b392-13976676cc16> I get the above error with the provided examples: print_hierarchy.py and tiny.rdl. To get the logging shown above I need to run python with -X faulthandler, otherwise it closes silently: no logging. I use Python 3.12.2 (also tried 3.14.0 and 3.12.0) pip freeze: antlr4-python3-runtime==4.13.2 colorama==0.4.6 Markdown==3.9 systemrdl-compiler==1.30.1 typing_extensions==4.15.0 The machine is Windows 11 Pro. I ran python via Powershell. The weird thing is that i dont see this error on any of my other machines. Just this one. Do you have an idea how i can debug this? A clear and concise description of what the bug is. Details like these can be helpful: - Sample SystemRDL code - Error message - Version numbers for the tool, Python, and OS *Expected behavior* I expect it to print the rdl hierarchy like the example does. *Additional context* Add any other context about the problem here. — Reply to this email directly, view it on GitHub <#297>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AC3W6I6363QRM346OP6422D3XYUUNAVCNFSM6AAAAACJH3P27KVHI2DSMVQWIX3LMV43ASLTON2WKOZTGUYTONJWGY2DEMQ> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[basberg]

I think so. Is a specific version required?

[amykyta3]

What you have should be good. That's very odd, so we can probably rule out a missing MSVC runtime as the issue.

Can you try rolling back the compiler to the prior version?

python3 -m pip install "systemrdl-compiler == 1.29.3"

I had made an update to the Antlr runtime, which could have affected this.

[basberg]

I used these examples since the new ones didnt work anymore:
https://github.com/SystemRDL/systemrdl-compiler/tree/v1.29.3/examples

pip freeze:
antlr4-python3-runtime==4.13.2
colorama==0.4.6
Markdown==3.9
systemrdl-compiler==1.29.3
typing_extensions==4.15.0