[llvm] [OFFLOAD] Stricter enforcement of user offload disable (PR #133470)

[Joseph Huber via llvm-commits]

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@@ -31,6 +32,12 @@ void initRuntime() {
   if (PM == nullptr)
     PM = new PluginManager();
 
+  if (OffloadPolicy::isOffloadDisabled()) {
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jhuber6 wrote:

Beat me to it, but I'm trying to look at what the code's doing. This will then call `registerLib` with the target image, which will do all the normal handling, however since we never initialized the plugins it'll find that nothing is registered and quit. The problem is that now we exit and the user destructor calls `deinitRuntime` with a ref count of zero, which underflows and now the whole thing explodes if you call it from a shard library.

https://github.com/llvm/llvm-project/pull/133470