[libc++][NFC] Add additional test case for modules issue in Objective-C++

[philnik]

libcxx/test/libcxx/containers/sequences/vector/erase.modules.compile.pass.mm

13

Is this not implicitly checked through .pass.mm?

[ldionne]

libcxx/test/libcxx/containers/sequences/vector/erase.modules.compile.pass.mm

13

No, it's not. I thought it was better to have it explicitly.

libcxx/test/libcxx/containers/sequences/vector/erase.modules.compile.pass.mm

+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// Make sure that we don't get a compiler error when trying to use std::vector::erase
+// from Objective-C++. This happened in Objective-C++ mode with modules enabled (rdar://106813461).
+
+// REQUIRES: objective-c++
+
+#include <vector>
+
+void f(std::vector<int> vec, std::vector<int>::iterator it) {
+    (void)vec.erase(it);
+}