[clang] [clang] Add test for CWG1807 (PR #77637)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,31 @@
+// 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,CXX98
+// 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 dr1807 { // dr1807: 3.0
+struct S {
+  S() {}
+  ~S() {}
+};
+
+void f() {
+  try {
+    S s[3];
+  } catch (...) {}
+}
+}
+
+// CHECK:              invoke void @dr1807::S::S(){{.+}}
+// CHECK-NEXT:         {{.+}} unwind label %lpad
+
+// CHECK-LABEL:      lpad:
----------------
erichkeane wrote:

> This test is using clang_cc1 with a fixed target. I don't see how different output is possible here.

See `-fdiscard-value-names`, which is pretty common on as a default on some downstreams, resource sensitive build bots, and even some folk's local builds.  

https://github.com/llvm/llvm-project/pull/77637