1 files changed, 24 insertions, 4 deletions
diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index 72e8b456822..b5228fc6c8c 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -194,16 +194,36 @@ Module *HeaderSearch::lookupModule(StringRef ModuleName, bool AllowSearch) {
   Module *Module = ModMap.findModule(ModuleName);
   if (Module || !AllowSearch || !HSOpts->ImplicitModuleMaps)
     return Module;
-  
+
+  StringRef SearchName = ModuleName;
+  Module = lookupModule(ModuleName, SearchName);
+
+  // The facility for "private modules" -- adjacent, optional module maps named
+  // module.private.modulemap that are supposed to define private submodules --
+  // is sometimes misused by frameworks that name their associated private
+  // module FooPrivate, rather than as a submodule named Foo.Private as
+  // intended. Here we compensate for such cases by looking in directories named
+  // Foo.framework, when we previously looked and failed to find a
+  // FooPrivate.framework.
+  if (!Module && SearchName.consume_back("Private"))
+    Module = lookupModule(ModuleName, SearchName);
+  return Module;
+}
+
+Module *HeaderSearch::lookupModule(StringRef ModuleName, StringRef SearchName) {
+  Module *Module = nullptr;
+
   // Look through the various header search paths to load any available module
   // maps, searching for a module map that describes this module.
   for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) {
     if (SearchDirs[Idx].isFramework()) {
-      // Search for or infer a module map for a framework.
+      // Search for or infer a module map for a framework. Here we use
+      // SearchName rather than ModuleName, to permit finding private modules
+      // named FooPrivate in buggy frameworks named Foo.
       SmallString<128> FrameworkDirName;
       FrameworkDirName += SearchDirs[Idx].getFrameworkDir()->getName();
-      llvm::sys::path::append(FrameworkDirName, ModuleName + ".framework");
-      if (const DirectoryEntry *FrameworkDir 
+      llvm::sys::path::append(FrameworkDirName, SearchName + ".framework");
+      if (const DirectoryEntry *FrameworkDir
             = FileMgr.getDirectory(FrameworkDirName)) {
         bool IsSystem
           = SearchDirs[Idx].getDirCharacteristic() != SrcMgr::C_User;