[llvm] [offload] Add Windows offload support (PR #187006)

[Nick Sarnie via llvm-commits]

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@@ -30,6 +30,19 @@ using namespace plugin;
 using namespace error;
 using namespace llvm::offload::debug;
 
+// Windows/MSVC doesn't support weak symbols properly, so provide a stub
+// implementation that will be used if compiler-rt is not linked.
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sarnex wrote:

Can we add a link explaining the specific problem?

https://github.com/llvm/llvm-project/pull/187006