diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -443,6 +443,10 @@
                         Optional<StringRef> Source) {
   StringRef Dir;
   StringRef File;
+  // Convert FileName to native path
+  SmallString<128> NativePath = FileName;
+  llvm::sys::path::native(NativePath);
+  FileName = NativePath.str();
   std::string RemappedFile = remapDIPath(FileName);
   std::string CurDir = remapDIPath(getCurrentDirname());
   SmallString<128> DirBuf;
@@ -558,7 +562,10 @@
             MainFile->getName().rsplit('.').second)
             .isPreprocessed())
       MainFileName = CGM.getModule().getName().str();
-
+    // Convert MainFileName to native path
+    SmallString<128> NativePath = (StringRef)MainFileName;
+    llvm::sys::path::native(NativePath);
+    MainFileName = (std::string)NativePath.str();
     CSKind = computeChecksum(SM.getMainFileID(), Checksum);
   }
 
diff --git a/clang/test/CodeGen/debug-info-mingw.c b/clang/test/CodeGen/debug-info-mingw.c
new file mode 100644
--- /dev/null
+++ b/clang/test/CodeGen/debug-info-mingw.c
@@ -0,0 +1,7 @@
+// RUN: rm -rf %t/UNIQUE_DIR && mkdir -p %t/UNIQUE_DIR
+// RUN: cp %s %t/UNIQUE_DIR/debug-info-mingw.c
+// RUN: %clang_cc1 -triple x86_64-w64-windows-gnu -debug-info-kind=limited -main-file-name debug-info-mingw.c %t/UNIQUE_DIR/debug-info-mingw.c -emit-llvm -o - | FileCheck %s
+int main() {
+}
+// CHECK: !DIFile(filename: "{{.+}}\\UNIQUE_DIR\\debug-info-mingw.c",
+// UNSUPPORTED: !system-windows