I now have another problem
dmd does not link my dependencies.
the dub json looks like this

{
	"name": "sdc",
	"description": "SDC's driver",
	"copyright": "Copyright © 2014, deadlnix",
	"authors": ["deadlnix"],
	"mainSourceFile" : "sdc/main.d",
	"libs" : ["d","d-llvm"],	
	"importPaths" : ["libd-llvm/src","libd-llvm/libd/src","libd-llvm/import"],
	"dependencies": {
		"libd-llvm":{"version":"~master","path":"libd-llvm"}	
	},
	"lflags" : ["-Llib"]
}

I had to add the dependency-libraries as libs and compile them through my old make system because otherwise the LLVM-libs (I added them manually to libs just as you suggested) are not available to libd-llvm.
libd-llvms dub.json looks like this:

{
	"name": "libd-llvm",
	"targetType": "library",
	"description": "SDC's llvm binding'",
	"copyright": "Copyright © 2014, deadlnix",
	"authors": ["deadlnix"],
	"importPaths" : ["import"],
	"libs" : [ "LLVMTableGen","LLVMArchive","LLVMInstrumentation","LLVMLinker","LLVMIRReader","LLVMBitReader","LLVMAsmParser","LLVMipo","LLVMVectorize",			"LLVMDebugInfo","LLVMOption","LLVMX86Disassembler","LLVMX86AsmParser","LLVMX86CodeGen","LLVMSelectionDAG","LLVMAsmPrinter","LLVMX86Desc","LLVMX86Info","LLVMX86AsmPrinter",			"LLVMX86Utils","LLVMMCDisassembler","LLVMMCParser","LLVMInterpreter","LLVMBitWriter","LLVMMCJIT","LLVMJIT","LLVMCodeGen","LLVMObjCARCOpts","LLVMScalarOpts","LLVMInstCombine", 		"LLVMTransformUtils","LLVMipa","LLVMAnalysis","LLVMRuntimeDyld","LLVMExecutionEngine","LLVMTarget","LLVMMC","LLVMObject","LLVMCore","LLVMSupport","z","pthread","stdc++","dl"
	],
	"dependencies": {
		"libd": {"version":"~master","path":"libd"}
	}
}