[llvm] [Offload] Implement `olShutDown` (PR #144055)

[Joseph Huber via llvm-commits]

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@@ -130,6 +131,9 @@ constexpr ol_platform_backend_t pluginNameToBackend(StringRef Name) {
 #include "Shared/Targets.def"
 
 void initPlugins() {
+  PlatformList = new PlatformVecT();
+  AllocInfoMap = new AllocInfoMapT();
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jhuber6 wrote:

Yeah that's a common problem with these libraries when you start mixing global initializers. We had to do similar hacks in the plugins. There's nothing stopping you from calling `ptr.release` instead of `delete`. Also, this is basically *the* global shared state as far as I can tell. That should be a single type instead of scattered around and put in random Meyer's singletons.

https://github.com/llvm/llvm-project/pull/144055