[clang] [Clang][NFC] Mark 3106 as implemented. (PR #192256)

[Vlad Serebrennikov via cfe-commits]

================
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -std=c++98 -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+// RUN: %clang_cc1 -std=c++11 -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+// RUN: %clang_cc1 -std=c++14 -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+// RUN: %clang_cc1 -std=c++17 -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+// RUN: %clang_cc1 -std=c++20 -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+// RUN: %clang_cc1 -std=c++23 -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+// RUN: %clang_cc1 -std=c++2c -fexceptions -fcxx-exceptions -pedantic-errors %s -verify-directives -verify=expected
+
+
+// expected-no-diagnostics
+
+namespace cwg3106 { // cwg3106: 2.7
+#if __cplusplus >= 201102L
----------------
Endilll wrote:

```suggestion
#if __cplusplus >= 201103L
```
At some point I will create a header with utilities for DR testing, which would include macros with the correct values of `__cplusplus` macro to avoid mistakes like this one.

https://github.com/llvm/llvm-project/pull/192256