r312580 - Fix memory leak after r312467. The ModuleMap is the owner of the global module object until it's reparented under a real module.

[Richard Smith via cfe-commits]

Author: rsmith
Date: Tue Sep  5 14:46:22 2017
New Revision: 312580

URL: http://llvm.org/viewvc/llvm-project?rev=312580&view=rev
Log:
Fix memory leak after r312467. The ModuleMap is the owner of the global module object until it's reparented under a real module.

Modified:
    cfe/trunk/include/clang/Lex/ModuleMap.h
    cfe/trunk/lib/Lex/ModuleMap.cpp

Modified: cfe/trunk/include/clang/Lex/ModuleMap.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Lex/ModuleMap.h?rev=312580&r1=312579&r2=312580&view=diff
==============================================================================
--- cfe/trunk/include/clang/Lex/ModuleMap.h (original)
+++ cfe/trunk/include/clang/Lex/ModuleMap.h Tue Sep  5 14:46:22 2017
@@ -82,22 +82,26 @@ class ModuleMap {
   
   /// \brief The directory used for Clang-supplied, builtin include headers,
   /// such as "stdint.h".
-  const DirectoryEntry *BuiltinIncludeDir;
+  const DirectoryEntry *BuiltinIncludeDir = nullptr;
   
   /// \brief Language options used to parse the module map itself.
   ///
   /// These are always simple C language options.
   LangOptions MMapLangOpts;
 
-  // The module that the main source file is associated with (the module
-  // named LangOpts::CurrentModule, if we've loaded it).
-  Module *SourceModule;
+  /// The module that the main source file is associated with (the module
+  /// named LangOpts::CurrentModule, if we've loaded it).
+  Module *SourceModule = nullptr;
+
+  /// The global module for the current TU, if we still own it. (Ownership is
+  /// transferred if/when we create an enclosing module.
+  std::unique_ptr<Module> PendingGlobalModule;
 
   /// \brief The top-level modules that are known.
   llvm::StringMap<Module *> Modules;
 
   /// \brief The number of modules we have created in total.
-  unsigned NumCreatedModules;
+  unsigned NumCreatedModules = 0;
 
 public:
   /// \brief Flags describing the role of a module header.

Modified: cfe/trunk/lib/Lex/ModuleMap.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Lex/ModuleMap.cpp?rev=312580&r1=312579&r2=312580&view=diff
==============================================================================
--- cfe/trunk/lib/Lex/ModuleMap.cpp (original)
+++ cfe/trunk/lib/Lex/ModuleMap.cpp Tue Sep  5 14:46:22 2017
@@ -256,8 +256,7 @@ ModuleMap::ModuleMap(SourceManager &Sour
                      const LangOptions &LangOpts, const TargetInfo *Target,
                      HeaderSearch &HeaderInfo)
     : SourceMgr(SourceMgr), Diags(Diags), LangOpts(LangOpts), Target(Target),
-      HeaderInfo(HeaderInfo), BuiltinIncludeDir(nullptr),
-      SourceModule(nullptr), NumCreatedModules(0) {
+      HeaderInfo(HeaderInfo) {
   MMapLangOpts.LineComment = true;
 }
 
@@ -747,10 +746,12 @@ std::pair<Module *, bool> ModuleMap::fin
 }
 
 Module *ModuleMap::createGlobalModuleForInterfaceUnit(SourceLocation Loc) {
-  auto *Result = new Module("<global>", Loc, nullptr, /*IsFramework*/ false,
-                            /*IsExplicit*/ true, NumCreatedModules++);
-  Result->Kind = Module::GlobalModuleFragment;
-  return Result;
+  assert(!PendingGlobalModule && "created multiple global modules");
+  PendingGlobalModule.reset(
+      new Module("<global>", Loc, nullptr, /*IsFramework*/ false,
+                 /*IsExplicit*/ true, NumCreatedModules++));
+  PendingGlobalModule->Kind = Module::GlobalModuleFragment;
+  return PendingGlobalModule.get();
 }
 
 Module *ModuleMap::createModuleForInterfaceUnit(SourceLocation Loc,
@@ -766,7 +767,10 @@ Module *ModuleMap::createModuleForInterf
   Modules[Name] = SourceModule = Result;
 
   // Reparent the current global module fragment as a submodule of this module.
+  assert(GlobalModule == PendingGlobalModule.get() &&
+         "unexpected global module");
   GlobalModule->setParent(Result);
+  PendingGlobalModule.release(); // now owned by parent
 
   // Mark the main source file as being within the newly-created module so that
   // declarations and macros are properly visibility-restricted to it.