Update Xcode toolchain locations for Xcode 15

[cjhowedev]

Brief Description

Xcode does not store its C++ headers at /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1 any longer. It seems they now need to be selected by their SDK, so it should be /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++ instead for Xcode 15+.

OS: macOS 14.4.1

Used headers

Used settings

Target: Clang

Other settings

Stack trace or incompilable generated code

Error: Could not find a valid C++ include folder: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1

[tritao]

Can you send a PR for this? Don't have a recent Mac machine at this time.

[cjhowedev]

The build doesn't seem to work under Rosetta x86_64 or arm64 on my M1 Macbook. Not sure if the compiled LLVM binaries for arm64 are working. We will likely need to get the arm64 build working for me to contribute, but this is something we also likely need to do for MacOS support going forward.