[llvm] [Offload] Add Error Codes to PluginInterface (PR #138258)

[Ross Brunton via llvm-commits]

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@@ -0,0 +1,40 @@
+//===- OffloadError.cpp - Error extensions for offload --------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "OffloadError.h"
+#include "llvm/Support/ErrorHandling.h"
+
+using namespace llvm;
+using namespace llvm::omp::target::plugin;
+
+namespace {
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
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RossBrunton wrote:

I've reworded it to (hopefully) give more details about the context.

https://github.com/llvm/llvm-project/pull/138258