1 files changed, 14 insertions, 11 deletions
diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index 60fd42bc1127..219c62663ebd 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -398,10 +398,11 @@ StringRef DirectoryLookup::getName() const {
 Optional<FileEntryRef> HeaderSearch::getFileAndSuggestModule(
     StringRef FileName, SourceLocation IncludeLoc, const DirectoryEntry *Dir,
     bool IsSystemHeaderDir, Module *RequestingModule,
-    ModuleMap::KnownHeader *SuggestedModule) {
+    ModuleMap::KnownHeader *SuggestedModule, bool OpenFile /*=true*/,
+    bool CacheFailures /*=true*/) {
   // If we have a module map that might map this header, load it and
   // check whether we'll have a suggestion for a module.
-  auto File = getFileMgr().getFileRef(FileName, /*OpenFile=*/true);
+  auto File = getFileMgr().getFileRef(FileName, OpenFile, CacheFailures);
   if (!File) {
     // For rare, surprising errors (e.g. "out of file handles"), diag the EC
     // message.
@@ -431,7 +432,8 @@ Optional<FileEntryRef> DirectoryLookup::LookupFile(
     SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
     Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
     bool &InUserSpecifiedSystemFramework, bool &IsFrameworkFound,
-    bool &IsInHeaderMap, SmallVectorImpl<char> &MappedName) const {
+    bool &IsInHeaderMap, SmallVectorImpl<char> &MappedName,
+    bool OpenFile) const {
   InUserSpecifiedSystemFramework = false;
   IsInHeaderMap = false;
   MappedName.clear();
@@ -451,9 +453,9 @@ Optional<FileEntryRef> DirectoryLookup::LookupFile(
       RelativePath->append(Filename.begin(), Filename.end());
     }
 
-    return HS.getFileAndSuggestModule(TmpDir, IncludeLoc, getDir(),
-                                      isSystemHeaderDirectory(),
-                                      RequestingModule, SuggestedModule);
+    return HS.getFileAndSuggestModule(
+        TmpDir, IncludeLoc, getDir(), isSystemHeaderDirectory(),
+        RequestingModule, SuggestedModule, OpenFile);
   }
 
   if (isFramework())
@@ -491,7 +493,7 @@ Optional<FileEntryRef> DirectoryLookup::LookupFile(
     Dest = HM->lookupFilename(Filename, Path);
   }
 
-  if (auto Res = HS.getFileMgr().getOptionalFileRef(Dest)) {
+  if (auto Res = HS.getFileMgr().getOptionalFileRef(Dest, OpenFile)) {
     FixupSearchPath();
     return *Res;
   }
@@ -840,7 +842,7 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
     SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
     Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
     bool *IsMapped, bool *IsFrameworkFound, bool SkipCache,
-    bool BuildSystemModule) {
+    bool BuildSystemModule, bool OpenFile, bool CacheFailures) {
   ConstSearchDirIterator CurDirLocal = nullptr;
   ConstSearchDirIterator &CurDir = CurDirArg ? *CurDirArg : CurDirLocal;
 
@@ -869,8 +871,9 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
     }
     // Otherwise, just return the file.
     return getFileAndSuggestModule(Filename, IncludeLoc, nullptr,
-                                   /*IsSystemHeaderDir*/false,
-                                   RequestingModule, SuggestedModule);
+                                   /*IsSystemHeaderDir*/ false,
+                                   RequestingModule, SuggestedModule, OpenFile,
+                                   CacheFailures);
   }
 
   // This is the header that MSVC's header search would have found.
@@ -1010,7 +1013,7 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
     Optional<FileEntryRef> File = It->LookupFile(
         Filename, *this, IncludeLoc, SearchPath, RelativePath, RequestingModule,
         SuggestedModule, InUserSpecifiedSystemFramework, IsFrameworkFoundInDir,
-        IsInHeaderMap, MappedName);
+        IsInHeaderMap, MappedName, OpenFile);
     if (!MappedName.empty()) {
       assert(IsInHeaderMap && "MappedName should come from a header map");
       CacheLookup.MappedName =