diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -2898,6 +2898,7 @@
 
     case ORIGINAL_PCH_DIR:
       F.OriginalDir = std::string(Blob);
+      ResolveImportedPath(F, F.OriginalDir);
       break;
 
     case MODULE_NAME:
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -1470,8 +1470,7 @@
     unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
 
     SmallString<128> OutputPath(OutputFile);
-
-    SM.getFileManager().makeAbsolutePath(OutputPath);
+    PreparePathForOutput(OutputPath);
     StringRef origDir = llvm::sys::path::parent_path(OutputPath);
 
     RecordData::value_type Record[] = {ORIGINAL_PCH_DIR};
diff --git a/clang/test/Modules/relative-original-dir.m b/clang/test/Modules/relative-original-dir.m
new file mode 100644
--- /dev/null
+++ b/clang/test/Modules/relative-original-dir.m
@@ -0,0 +1,7 @@
+// RUN: rm -rf %t/normal-module-map
+// RUN: mkdir -p %t
+// RUN: cp -r %S/Inputs/normal-module-map %t
+// RUN: %clang_cc1 -fmodules -fno-implicit-modules -fmodule-name=libA -emit-module %t/normal-module-map/module.map -o %t/normal-module-map/outdir/mod.pcm
+// RUN: llvm-bcanalyzer --dump --disable-histogram %t/normal-module-map/outdir/mod.pcm | FileCheck %s
+
+// CHECK: <ORIGINAL_PCH_DIR abbrevid=7/> blob data = 'outdir'