diff --git a/clang/test/VFS/relative-path-errors.c b/clang/test/VFS/relative-path-errors.c
new file mode 100644
--- /dev/null
+++ b/clang/test/VFS/relative-path-errors.c
@@ -0,0 +1,8 @@
+// RUN: mkdir -p %t
+// RUN: cd %t
+// RUN: echo '{"roots": [],"version": 0}' > %t.yaml
+// RUN: cp %s main.c
+// RUN: not %clang_cc1 -ivfsoverlay %t.yaml main.c 2>&1 | FileCheck %s
+
+// CHECK: {{^}}main.c:8:1: error:
+foobarbaz
diff --git a/llvm/lib/Support/VirtualFileSystem.cpp b/llvm/lib/Support/VirtualFileSystem.cpp
--- a/llvm/lib/Support/VirtualFileSystem.cpp
+++ b/llvm/lib/Support/VirtualFileSystem.cpp
@@ -2013,7 +2013,7 @@
   ErrorOr<RedirectingFileSystem::LookupResult> Result = lookupPath(Path);
   if (!Result) {
     if (shouldFallBackToExternalFS(Result.getError()))
-      return ExternalFS->openFileForRead(Path);
+      return ExternalFS->openFileForRead(Path_);
     return Result.getError();
   }
 
@@ -2026,7 +2026,7 @@
   auto ExternalFile = ExternalFS->openFileForRead(ExtRedirect);
   if (!ExternalFile) {
     if (shouldFallBackToExternalFS(ExternalFile.getError(), Result->E))
-      return ExternalFS->openFileForRead(Path);
+      return ExternalFS->openFileForRead(Path_);
     return ExternalFile;
   }