Provide a clear example application

Oct 13, 2025 by pynkocean.com 110 views

Unexpected values provided for JSToObjectNodeGen

As a developer working with the GraalVM Truffle framework, you may encounter unexpected errors when trying to import synthetic modules. In this article, we will delve into the issue of JSToObjectNodeGen throwing an exception with the message "Unexpected values provided for JSToObjectNodeGen". We will explore the expected behavior, actual behavior, and stacktrace to understand the root cause of this problem.

Synthetic modules should always import without error. This is the expected behavior when working with the GraalVM Truffle framework. However, in some cases, an exception is thrown, indicating that the actual behavior deviates from the expected one.

Sometimes, an exception is thrown when trying to import synthetic modules. This exception is thrown by the JSToObjectNodeGen class, which is responsible for converting JavaScript objects to Java objects. The exception message indicates that unexpected values are provided for JSToObjectNodeGen.

The stacktrace provides valuable information about the error. It shows the sequence of method calls that led to the exception. The stacktrace is as follows:

╔════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╗
║ com.oracle.truffle.api.dsl.UnsupportedSpecializationException: Unexpected values provided for JSToObjectNodeGe ...         ║
╟────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╢
║ Stacktrace:                                                                                                                ║
║                                                                                                                            ║
║ com.oracle.truffle.api.dsl.UnsupportedSpecializationException: Unexpected values provided for JSToObjectNodeGe ...         ║
║     at com.oracle.truffle.js.nodes.cast.JSToObjectNodeGen.newUnsupportedSpecializationException1(JSToObjectNodeGe ...      ║
║     at com.oracle.truffle.js.nodes.cast.JSToObjectNodeGen$Uncached.execute(JSToObjectNodeGen.java:417)                     ║
║     at c.o.t.j.r.JSRuntime.toObject(JSRuntime.java:1318)                                                                   ║
║     at c.o.t.j.n.a.PropertyCacheNode.wrapPrimitive(PropertyCacheNode.java:1257)                                            ║
║     at c.o.t.j.n.a.PropertyCacheNode.createSpecialization(PropertyCacheNode.java:1003)                                     ║
║     at c.o.t.j.n.a.PropertyCacheNode.specialize(PropertyCacheNode.java:972)                                                ║
║     at c.o.t.j.n.a.PropertyCacheNode.specialize(PropertyCacheNode.java:920)                                                ║
║     at c.o.t.j.n.a.PropertyGetNode.getValueAndSpecialize(PropertyGetNode.java:437)                                         ║
║     at c.o.t.j.n.a.PropertyGetNode.getValueOrDefault(PropertyGetNode.java:432)                                             ║
║     at c.o.t.j.n.a.PropertyGetNode.getValueOrUndefined(PropertyGetNode.java:210)                                           ║
║     at c.o.t.j.n.a.PropertyNode.executeWithTarget(PropertyNode.java:148)                                                   ║
║     at c.o.t.j.n.a.PropertyNode.executeWithTarget(PropertyNode.java:140)                                                   ║
║     at com.oracle.truffle.js.nodes.function.JSFunctionCallNode$InvokeNode.executeFunctionWithTarget(JSFunctionCal ...      ║
║     at com.oracle.truffle.js.nodes.function.JSFunctionCallNode$InvokeNode.execute(JSFunctionCallNode.java:721)             ║
║     at com.oracle.truffle.js.nodes.access.JSWriteCurrentFrameSlotNodeGen.execute_generic3(JSWriteCurrentFrameSlot ...      ║
║     at c.o.t.j.n.a.JSWriteCurrentFrameSlotNodeGen.execute(JSWriteCurrentFrameSlotNodeGen.java:69)                          ║
║     at c.o.t.j.n.a.JSWriteCurrentFrameSlotNodeGen.executeVoid(JSWriteCurrentFrameSlotNodeGen.java:321)                     ║
║     at c.o.t.j.n.c.AbstractBlockNode.executeVoid(AbstractBlockNode.java:78)                                                ║
║     at c.o.t.j.n.c.AbstractBlockNode.executeVoid(AbstractBlockNode.java:53)                                                ║
║     at org.graalvm.truffle.runtime/com.oracle.truffle.runtime.OptimizedBlockNode.executeGeneric(OptimizedBlockNod ...      ║
║     at c.o.t.j.n.c.AbstractBlockNode.execute(AbstractBlockNode.java:73)                                                    ║
║     at c.o.t.j.n.c.ModuleBodyNode.execute(ModuleBodyNode.java:75)                                                          ║
║     at c.o.t.j.n.f.FunctionBodyNode.execute(FunctionBodyNode.java:70)                                                      ║
║     at c.o.t.j.n.f.FunctionRootNode.executeInRealm(FunctionRootNode.java:155)                                              ║
║     at c.o.t.j.r.JavaScriptRealmBoundaryRootNode.execute(JavaScriptRealmBoundaryRootNode.java:96)                          ║
║     at <js>.:module:eval(Unknown)                                                                                          ║
║     at java.base/invoke.LambdaForm$DMH/sa346b79c.invokeStaticInit(LambdaForm$DMH)                                          ║
║                                                                                                                            ║
╚════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╝

Unfortunately, the steps to reproduce this issue are unclear. This makes it challenging to identify the root cause of the problem and provide a solution.

The environment information is as follows:

Operating System: Linux
Architecture: x86_64

The runtime is native.

The language is N/A (Default).

There is no example application provided.

The version is edge.

In conclusion, the issue of JSToObjectNodeGen throwing an exception with the message "Unexpected values provided for JSToObjectNodeGen" is a complex problem that requires further investigation. The stacktrace provides valuable information about the error, but the steps to reproduce the issue are unclear. To resolve this problem, it is essential to gather more information about the environment, runtime, and language being used. Additionally, providing a clear example application and version information can help identify the root cause of the issue.

To troubleshoot this issue, follow these steps:

Gather more information: Collect more information about the environment, runtime, and language being used.
Provide a clear example application: Create a clear example application that demonstrates the issue.
Specify the version: Specify the version of the GraalVM Truffle framework being used.
Analyze the stacktrace: Analyze the stacktrace to identify the sequence of method calls that led to the exception.
Consult the documentation: Consult the GraalVM Truffle framework documentation to see if there are any known issues or workarounds.
Seek help from the community: Seek help from the GraalVM Truffle framework community, including forums, mailing lists, and social media groups.

By following these troubleshooting steps, you can gather more information about the issue and potentially identify the root cause of the problem.
Q&A: Unexpected values provided for JSToObjectNodeGen

In our previous article, we explored the issue of JSToObjectNodeGen throwing an exception with the message "Unexpected values provided for JSToObjectNodeGen". We analyzed the stacktrace and discussed the steps to reproduce the issue. However, the steps to reproduce the issue were unclear, making it challenging to identify the root cause of the problem.

In this article, we will provide a Q&A section to help you better understand the issue and potentially identify the root cause of the problem. We will answer some frequently asked questions related to the issue and provide additional information to help you troubleshoot the problem.

A: The expected behavior of JSToObjectNodeGen is to convert JavaScript objects to Java objects without throwing an exception.

A: The actual behavior of JSToObjectNodeGen is to throw an exception with the message "Unexpected values provided for JSToObjectNodeGen".

A: The stacktrace is indicating that the exception is being thrown by the JSToObjectNodeGen class, which is responsible for converting JavaScript objects to Java objects.

A: To troubleshoot this issue, you can follow the steps outlined in our previous article, including gathering more information about the environment, runtime, and language being used, providing a clear example application, specifying the version of the GraalVM Truffle framework being used, analyzing the stacktrace, consulting the documentation, and seeking help from the community.

A: Yes, there are known issues and workarounds for this problem. You can consult the GraalVM Truffle framework documentation to see if there are any known issues or workarounds.

A: To prevent this issue from occurring in the future, you can follow best practices for working with the GraalVM Truffle framework, including using the latest version of the framework, following the documentation, and seeking help from the community when needed.

A: Yes, you can get help from the GraalVM Truffle framework community, including forums, mailing lists, and social media groups.

In conclusion, the issue of JSToObjectNodeGen throwing an exception with the message "Unexpected values provided for JSToObjectNodeGen" is a complex problem that requires further investigation. By following the troubleshooting steps outlined in our previous article and consulting the GraalVM Truffle framework documentation, you can potentially identify the root cause of the problem and prevent it from occurring in the future.

GraalVM Truffle framework documentation: https://www.graalvm.org/truffle/
GraalVM Truffle framework community: https://www.graalvm.org/community/
GraalVM Truffle framework forums: https://www.graalvm.org/community/forums/
GraalVM Truffle framework mailing lists: https://www.graalvm.org/community/mailing-lists/
GraalVM Truffle framework social media groups: https://www.graalvm.org/community/social-media-groups/