[RaphaelFakhri]

Summary

wasmtime_global_set returns a wasmtime_error_t*, but the P/Invoke in Global.Native declares it as void. When the native call fails, the error is dropped and its allocation leaks, so Global.SetValue and Global.Accessor<T>.SetValue return normally even though the global keeps its old value.

One way to trigger this is to set a funcref global to a Function that belongs to a different Store. Table.SetElement throws a WasmtimeException in that case. Global.SetValue throws nothing and leaves the global unchanged.

Fixes #392.

Changes

• Declare wasmtime_global_set as returning IntPtr, matching include/wasmtime/global.h.
• In Global.SetValue and Global.Accessor<T>.SetValue, throw WasmtimeException.FromOwnedError when the call returns an error. Table.SetElement already handles errors the same way.
• Add tests that set a funcref global to a function from another store through both APIs. The tests expect a WasmtimeException and check that the global still holds a null funcref.

Testing

• dotnet test tests/Wasmtime.Tests.csproj --filter "FullyQualifiedName~GlobalImportBindingTests": before the fix, the 2 new tests fail with "no exception was thrown". After the fix, all 14 tests pass.
• dotnet test tests/Wasmtime.Tests.csproj: 479 passed, 2 skipped, 0 failed (Linux x64, net9.0).

[martindevans]

Thanks for investigating and fixing this 👍