diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -136,14 +136,17 @@
   if (!this->VFS)
     this->VFS = llvm::vfs::getRealFileSystem();
 
-  if (llvm::sys::path::is_relative(SysRoot)) {
-    SysRoot = GetResourcesPath(ClangExecutable, SysRoot);
-  }
-
   Name = std::string(llvm::sys::path::filename(ClangExecutable));
   Dir = std::string(llvm::sys::path::parent_path(ClangExecutable));
   InstalledDir = Dir; // Provide a sensible default installed dir.
 
+  if (llvm::sys::path::is_relative(SysRoot)) {
+    // Prepend InstalledDir if SysRoot is relative
+    SmallString<128> fullpath(InstalledDir);
+    llvm::sys::path::append(fullpath, SysRoot);
+    SysRoot = std::string(fullpath);
+  }
+
 #if defined(CLANG_CONFIG_FILE_SYSTEM_DIR)
   SystemConfigDir = CLANG_CONFIG_FILE_SYSTEM_DIR;
 #endif