[clang] [clang][driver] Add \<executable\>/../include/c++/v1 to include path on Darwin (PR #70817)

[Louis Dionne via cfe-commits]

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@@ -172,3 +172,32 @@
 // RUN:               --check-prefix=CHECK-LIBCXX-STDLIB-UNSPECIFIED %s
 // CHECK-LIBCXX-STDLIB-UNSPECIFIED: "-cc1"
 // CHECK-LIBCXX-STDLIB-UNSPECIFIED: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+
+// ----------------------------------------------------------------------------
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ldionne wrote:

BTW this looks good to me apart from these test improvements.

https://github.com/llvm/llvm-project/pull/70817