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

[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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cor3ntin wrote:

I agree with @Endilll.
We should understand _why_ the behavior in older language modes is different.
I would recommend trying to use a debugger to try to see why we are not passing in that code path.
The difference in behavior across language modes looks like a bug that should be fixed, rather than a change in expected behavior

(in all language modes, if a constructor is called, that constructor might have side effects)

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