[clang] [llvm] [openmp] ReworkCtorDtor (PR #71739)

[Joseph Huber via cfe-commits]

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@@ -95,7 +95,7 @@ using namespace llvm;
 static cl::opt<bool>
     LowerCtorDtor("nvptx-lower-global-ctor-dtor",
                   cl::desc("Lower GPU ctor / dtors to globals on the device."),
-                  cl::init(false), cl::Hidden);
+                  cl::init(true), cl::Hidden);
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jhuber6 wrote:

This was the easiest way to get the desired effect. Passing `--nvptx-lower-glocal-ctor-dtor` is subtly broken because I think it will fail if the user didn't build with the NVPTX target. The OpenMP runtime is supposed to be buildable for NVPTX even without backend support so I was worried it would degrade that. Do you think I could check for `openmp` module data and set it based off of that? OpenMP always emits an `openmp` global flag.

https://github.com/llvm/llvm-project/pull/71739