[llvm] [Offload] Ensure all `llvm::Error`s are handled (PR #137339)

[Ross Brunton via llvm-commits]

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@@ -308,9 +308,11 @@ ol_impl_result_t olMemAlloc_impl(ol_device_handle_t Device,
                                  void **AllocationOut) {
   auto Alloc =
       Device->Device->dataAlloc(Size, nullptr, convertOlToPluginAllocTy(Type));
-  if (!Alloc)
+  if (!Alloc) {
+    llvm::consumeError(Alloc.takeError());
     return {OL_ERRC_OUT_OF_RESOURCES,
             formatv("Could not create allocation on device {0}", Device).str()};
+  }
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RossBrunton wrote:

I only used that function in cases where there was no existing error code. For functions like this, all errors from allocations should result in `OL_ERRC_OUT_OF_RESOURCES`.

https://github.com/llvm/llvm-project/pull/137339