[libcxx-commits] [libcxx] [libc++] Fix header deprecations (PR #163356)

[Louis Dionne via libcxx-commits]

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@@ -14,12 +14,6 @@
 // UNSUPPORTED: c++03, c++11, c++14
 // UNSUPPORTED: clang-modules-build
 
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ldionne wrote:

If I understand correctly, what's being fixed is that before this patch, this test only passes because we're using `-I include/c++/v1` and disabling `#pragma system_header`. After this patch, this test would now pass if we were using `-isystem` (which is what end users do). However, we're not actually exercising that as part of this patch. Could we exercise that somehow?

For example, might it make sense to use `-isystem` for `.verify.cpp` tests from the Lit configuration? Or not disable `#pragma system_header` for those tests? We control that from here: https://github.com/llvm/llvm-project/blob/main/libcxx/utils/libcxx/test/params.py#L299

It's quite hacky, but we could perhaps do something like `-U_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER` when compiling `.verify.cpp` tests? Not very pretty though.

https://github.com/llvm/llvm-project/pull/163356