[clang] [clang] Enable '-verify-directives' mode in C++ DR tests (PR #187219)

[via cfe-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 53312 tests passed
* 1030 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### Clang
<details>
<summary>Clang.CXX/drs/cwg390.cpp</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
c:\_work\llvm-project\llvm-project\build\bin\clang.exe -cc1 -internal-isystem C:\_work\llvm-project\llvm-project\build\lib\clang\23\include -nostdsysteminc -std=c++98 C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\clang.exe' -cc1 -internal-isystem 'C:\_work\llvm-project\llvm-project\build\lib\clang\23\include' -nostdsysteminc -std=c++98 'C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp' -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify
# .---command stderr------------
# | error: all diagnostics were successfully matched, but out-of-order directives were found: 
# |   'expected-warning' at line 13 in C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp: call to pure virtual member function 'f' has undefined behavior; overrides of 'f' in subclasses are not available in the constructor of 'cwg390::A<int>'
# |     matches diagnostic at line 12, but diagnostic at line 19 was emitted first:
# |       type 'int' cannot be used prior to '::' because it has no members
# |   'expected-note' at line 14 in C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp: in instantiation of member function 'cwg390::A<int>::A' requested here
# |     matches diagnostic at line 23, but diagnostic at line 23 was emitted first:
# |       in instantiation of member function 'cwg390::A<int>::~A' requested here
# |   'expected-note' at line 15 in C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp: 'f' declared here
# |     matches diagnostic at line 16, but diagnostic at line 12 was emitted first:
# |       call to pure virtual member function 'f' has undefined behavior; overrides of 'f' in subclasses are not available in the constructor of 'cwg390::A<int>'
# |   'expected-error' at line 20 in C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp: type 'int' cannot be used prior to '::' because it has no members
# |     matches diagnostic at line 19, but diagnostic at line 23 was emitted first:
# |       in instantiation of member function 'cwg390::A<int>::A' requested here
# |   'expected-note' at line 21 in C:\_work\llvm-project\llvm-project\clang\test\CXX\drs\cwg390.cpp: in instantiation of member function 'cwg390::A<int>::~A' requested here
# |     matches diagnostic at line 23, but diagnostic at line 16 was emitted first:
# |       'f' declared here
# | 5 errors generated.
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/187219