[clang] [clang] Add tests for DRs about inheriting constructors (PR #79981)

[via cfe-commits]

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@@ -0,0 +1,33 @@
+// RUN: %clang_cc1 -std=c++98 %s -triple x86_64-linux-gnu -emit-llvm -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 -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK,SINCE-CXX11
+// RUN: %clang_cc1 -std=c++14 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK,SINCE-CXX11
+// RUN: %clang_cc1 -std=c++17 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK,SINCE-CXX11
+// RUN: %clang_cc1 -std=c++20 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK,SINCE-CXX11
+// RUN: %clang_cc1 -std=c++23 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK,SINCE-CXX11
+// RUN: %clang_cc1 -std=c++2c %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK,SINCE-CXX11
+
+namespace dr2504 { // dr2504: no
+#if __cplusplus >= 201103L
+struct V { V() = default; V(int); };
+struct Q { Q(); };
+struct A : virtual V, Q {
+  using V::V;
+  A() = delete;
+};
+int bar() { return 42; }
+struct B : A {
+  B() : A(bar()) {}  // ok
+};
+struct C : B {};
+void foo() { C c; } // bar is not invoked, because the V subobject is not initialized as part of B
+#endif
+}
+
+// CHECK: {{.*}}
+
+// SINCE-CXX11-LABEL: define linkonce_odr void @dr2504::B::B()
+// SINCE-CXX11-NOT:     br
+// SINCE-CXX11:         call noundef i32 @dr2504::bar()
+// SINCE-CXX11-NOT:     br
+// SINCE-CXX11:         call void @dr2504::A::A(int)
+// SINCE-CXX11-LABEL: }
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cor3ntin wrote:

Can you add a fixme and create an issue?

https://github.com/llvm/llvm-project/pull/79981