[libcxx] [llvm] [libc++] Deprecate and remove meaningless `<cxxx>` headers (PR #111615)

[Louis Dionne via llvm-commits]

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@@ -24,7 +24,11 @@
 #endif
 
 #ifdef __cplusplus
-#  include <ccomplex>
+#  if _LIBCPP_STD_VER >= 17
+#    include <complex>
+#  else
+#    include <ccomplex>
+#  endif
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ldionne wrote:

Similarly, why not include `<complex>` unconditionally instead?

https://github.com/llvm/llvm-project/pull/111615