Failure Signature
An OPC UA server ported to an ARM Linux platform exits when pServer->start() returns -1. The more specific failure is a segmentation fault while the runtime binds OpcUa_Thread_Delete from libuastack.so.
| Observation | What it establishes |
|---|---|
start() returns -1
|
Server startup failed, but this return value alone does not identify the cause. |
Fault occurs while binding OpcUa_Thread_Delete
|
Focus the diagnosis on the executable, stack library, SDK libraries, and cross-build environment. |
nm lists the symbol in libuastack.so
|
The library exports a symbol with that name; this does not prove that all binaries are mutually compatible. |
Likely Root Cause
The evidence points to a build-environment or cross-toolchain mismatch. Check whether the OPC UA stack, SDK libraries, and server executable were all built with the same compiler and compatible toolchain setup. Treat this as the leading hypothesis rather than a confirmed cause until a consistent rebuild removes the fault.
A successful symbol lookup does not eliminate this hypothesis. The command below confirms symbol presence only; it does not verify binary-interface compatibility among separately built components.
nm libuastack.so | grep "OpcUa_Thread_Delete"Corrective Procedure
- Identify the compiler and cross-toolchain configuration used for the server executable, OPC UA stack, and SDK libraries.
- Confirm that every component targets the same ARM Linux platform and was produced with the same compiler toolchain.
- Correct any inconsistent toolchain configuration, then rebuild the stack, SDK libraries, and server application as one consistent artifact set.
- Deploy the rebuilt executable and its matching libraries together so an older or separately built
libuastack.sois not mixed with the new application.
Verification
Run the rebuilt server and verify that execution proceeds beyond pServer->start(), the return value is no longer -1, and no segmentation fault occurs while binding OpcUa_Thread_Delete. If the fault remains, preserve the exact binding message and compare the compiler and toolchain provenance of every loaded stack and SDK library; the available evidence does not establish another product-specific cause.
FAQ
Why does my OPC UA server return error code -1 on ARM Linux?
The evidence indicates a likely mismatch between the compiler or cross-toolchain used for the server, OPC UA stack, and SDK libraries. Rebuild all components with one consistent toolchain and deploy the matching artifacts together.
Why can OpcUa_Thread_Delete cause a segmentation fault when nm finds it?
nm confirms that libuastack.so exports the named symbol, but it does not prove binary compatibility with the executable and other SDK libraries. Check the complete build toolchain rather than treating symbol presence as sufficient verification.
How do I verify the OPC UA server rebuild fixed the startup failure?
Start the rebuilt application and confirm that pServer->start() does not return -1 and that binding OpcUa_Thread_Delete no longer produces a segmentation fault.
