diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -819,9 +819,19 @@
       bool IncluderIsSystemHeader =
           Includer ? getFileInfo(Includer).DirInfo != SrcMgr::C_User :
           BuildSystemModule;
-      if (Optional<FileEntryRef> FE = getFileAndSuggestModule(
-              TmpDir, IncludeLoc, IncluderAndDir.second, IncluderIsSystemHeader,
-              RequestingModule, SuggestedModule)) {
+
+      Optional<FileEntryRef> FE = getFileAndSuggestModule(
+          TmpDir, IncludeLoc, IncluderAndDir.second, IncluderIsSystemHeader,
+          RequestingModule, SuggestedModule);
+
+      // If this is a system header, we should also search from the current
+      // working directory and not the directory of the module map.
+      if (!FE && IncluderIsSystemHeader)
+        FE = getFileAndSuggestModule(
+            Filename, IncludeLoc, IncluderAndDir.second, IncluderIsSystemHeader,
+            RequestingModule, SuggestedModule);
+
+      if (FE) {
         if (!Includer) {
           assert(First && "only first includer can have no file");
           return FE;