StackOverflowError if HomotopyContinuation.System is passed a SymEngine.Basic

[GGooeytoe]

I was trying to use SymEngine's slightly more powerful symbolic facilities to build by expressions for eventual use in a HomotopyContinuation.System when I discovered that if you pass a SymEngine.Basic to HomotopyContinuation.System, it will try to convert it, fail, and overflow the stack. Presumably this capability is not supported, but this seems like a pretty undesirable way to fail. On a related note, is there a recommended way to interface SymEngine and HomotopyContinuation/ModelKit? I see from the source that ModelKit uses some SymEngine features, but they apparently aren't transparently compatible.

Reproducer:

import HomotopyContinuation
import SymEngine
x=SymEngine.symbols("x")
C=HomotopyContinuation.System([x],variables=[x])

Produces:

Warning: detected a stack overflow; program state may be corrupted, so further execution might be unreliable.
ERROR: StackOverflowError:
Stacktrace:
     [1] convert(::Type{HomotopyContinuation.ModelKit.Expression}, x::SymEngine.Basic)
       @ Base .\number.jl:7
     [2] HomotopyContinuation.ModelKit.Expression(T::SymEngine.Basic)
       @ HomotopyContinuation.ModelKit C:\Users\gmgutow\.julia\packages\HomotopyContinuation\98yZ2\src\model_kit\symengine.jl:46
--- the above 2 lines are repeated 39990 more times ---
 [79983] convert(::Type{HomotopyContinuation.ModelKit.Expression}, x::SymEngine.Basic)
       @ Base .\number.jl:7

System Info
Windows 11
Julia 1.12.6
HomotopyContinuation v2.20.0
SymEngine v0.13.2

[PBrdng]

Hi, this is true: there is no complete compatibility (yet) with SymEngine. I think no one has had the time to do this so far. I will try to look into it, but understand that this is not top priority at the moment.

[GGooeytoe]

I was able to convert from SymEngine to ModelKit using SymEngine’s lambdify so this isn’t blocking me or anything. Just wanted to document the current behavior.On Jul 11, 2026, at 1:45 AM, Paul Breiding ***@***.***> wrote:PBrdng left a comment (JuliaHomotopyContinuation/HomotopyContinuation.jl#716) Hi, this is true: there is no complete compatibility (yet) with SymEngine. I think no one has had the time to do this so far. I will try to look into it, but understand that this is not top priority at the moment. —Reply to this email directly, view it on GitHub, or unsubscribe.Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS and Android. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.***>