[clang] [clang] Add some CodeGen tests for CWG 2xx issues (PR #80823)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,43 @@
+// RUN: %clang_cc1 -std=c++98 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++11 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++14 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++17 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++20 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++23 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++2c %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O0 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+
+// RUN: %clang_cc1 -std=c++98 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++11 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++14 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++17 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++20 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++23 %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++2c %s -triple x86_64-linux-gnu -emit-llvm -disable-llvm-passes -O3 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+
+#if __cplusplus == 199711L
+#define NOTHROW throw()
+#else
+#define NOTHROW noexcept(true)
+#endif
+
+namespace dr201 { // dr201: 2.8
----------------
erichkeane wrote:

> I'll update the test to make it more clear, but I test whether a temporary is destroyed at the end of full expression. Which I believe is what 201 is about, contrary to its title.

TBH, I think this is one of those "textual pendentry" type DRs where two sentences were inconsistent.  It is complaining that in the expression: `B b = A();` whether the call to `B::B` is 'part' of the full expression (so the deletion of the temporary isn't really meaningful).

It was never contentous based on my reading whether the temporary was deleted 'end of statement' (in fact, it was, in 1 sentence deleted AFTER init, which was AFTER end of statement, but that wasn't the case in the other sentence).

Because of this, I think your test is reasonably fine, except I'd add a check for the call to `B::B` before `A::~A`.

Also, it might be valuable to get the 'default argument to a default constructor called in array' is deleted BEFORE the initialization of the array.


https://github.com/llvm/llvm-project/pull/80823