[clang] [Clang][Sema]: Allow copy constructor side effects (PR #81127)

[Vlad Serebrennikov via cfe-commits]

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@@ -1,5 +1,5 @@
 // RUN: %clang_cc1 -fsyntax-only -Wunused-variable -Wunused-label -Wno-c++1y-extensions -verify %s
-// RUN: %clang_cc1 -fsyntax-only -Wunused-variable -Wunused-label -Wno-c++1y-extensions -verify -std=gnu++11 %s
+// RUN: %clang_cc1 -fsyntax-only -Wunused-variable -Wunused-label -Wno-c++1y-extensions -verify -std=gnu++17 %s
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Endilll wrote:

As much as hate to say this, this is a point to investigate. What should happen in language modes before 17? Maybe mandatory copy elision introduced in 17 is involved?
I don't think this patch is supposed to remove a language mode all other tests have been tested in. That's simply out of scope of the PR.

https://github.com/llvm/llvm-project/pull/81127