Merge pull request #295358 from SharzyL/llvm17_libunwind

llvmPackages_17.clangUseLLVM: apply omitted #220520

pkgs/development/compilers/llvm/17/default.nix

···
           (!stdenv.targetPlatform.isWasm && stdenv.targetPlatform.useLLVM or false)
           "-lunwind"
         ++ lib.optional stdenv.targetPlatform.isWasm "-fno-exceptions";
+      nixSupport.cc-ldflags = lib.optionals (!stdenv.targetPlatform.isWasm) [ "-L${targetLlvmLibraries.libunwind}/lib" ];
     };
 
     clangNoLibcxx = wrapCCWith rec {