[clang] [libc] [libcxx] [libc][libcxx] Support for building libc++ against LLVM libc (PR #99287)

[Louis Dionne via cfe-commits]

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@@ -0,0 +1,34 @@
+#===============================================================================
+# Define targets for linking against the selected C library
+#
+# After including this file, the following targets are defined:
+# - libcxx-libc-headers: An interface target that allows getting access to the
+#                        headers of the selected C library.
+# - libcxx-libc-shared: A target representing the selected shared C library.
+# - libcxx-libm-shared: A target representing the selected shared C math library.
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ldionne wrote:

Is it not possible to roll this up into the libc target? From the libc++ side, we'd like to have the illusion that `libm` is nothing but an implementation detail of `libc`, kind of like `-latomic`.

https://github.com/llvm/llvm-project/pull/99287