[PCH/Modules] Check that the specific module cache path the PCH was built with, is the same as

the one in the current compiler invocation. If they differ reject the PCH.

This protects against the badness occurring from getting modules loaded from different module caches (see crashes).

rdar://19889860

llvm-svn: 229909

1 files changed, 55 insertions, 8 deletions

diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 3125b8e43e9..7774b7b1c6e 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -108,9 +108,12 @@ ChainedASTReaderListener::ReadFileSystemOptions(const FileSystemOptions &FSOpts,
 }
 
 bool ChainedASTReaderListener::ReadHeaderSearchOptions(
-    const HeaderSearchOptions &HSOpts, bool Complain) {
-  return First->ReadHeaderSearchOptions(HSOpts, Complain) ||
-         Second->ReadHeaderSearchOptions(HSOpts, Complain);
+    const HeaderSearchOptions &HSOpts, StringRef SpecificModuleCachePath,
+    bool Complain) {
+  return First->ReadHeaderSearchOptions(HSOpts, SpecificModuleCachePath,
+                                        Complain) ||
+         Second->ReadHeaderSearchOptions(HSOpts, SpecificModuleCachePath,
+                                         Complain);
 }
 bool ChainedASTReaderListener::ReadPreprocessorOptions(
     const PreprocessorOptions &PPOpts, bool Complain,
@@ -464,7 +467,7 @@ collectMacroDefinitions(const PreprocessorOptions &PPOpts,
     Macros[MacroName] = std::make_pair(MacroBody, false);
   }
 }
-         
+
 /// \brief Check the preprocessor options deserialized from the control block
 /// against the preprocessor options in an existing preprocessor.
 ///
@@ -591,6 +594,36 @@ bool PCHValidator::ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
                                   PP.getLangOpts());
 }
 
+/// Check the header search options deserialized from the control block
+/// against the header search options in an existing preprocessor.
+///
+/// \param Diags If non-null, produce diagnostics for any mismatches incurred.
+static bool checkHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
+                                     StringRef SpecificModuleCachePath,
+                                     StringRef ExistingModuleCachePath,
+                                     DiagnosticsEngine *Diags,
+                                     const LangOptions &LangOpts) {
+  if (LangOpts.Modules) {
+    if (SpecificModuleCachePath != ExistingModuleCachePath) {
+      if (Diags)
+        Diags->Report(diag::err_pch_modulecache_mismatch)
+          << SpecificModuleCachePath << ExistingModuleCachePath;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool PCHValidator::ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
+                                           StringRef SpecificModuleCachePath,
+                                           bool Complain) {
+  return checkHeaderSearchOptions(HSOpts, SpecificModuleCachePath,
+                                  PP.getHeaderSearchInfo().getModuleCachePath(),
+                                  Complain ? &Reader.Diags : nullptr,
+                                  PP.getLangOpts());
+}
+
 void PCHValidator::ReadCounter(const ModuleFile &M, unsigned Value) {
   PP.setCounterValue(Value);
 }
@@ -4191,16 +4224,19 @@ namespace {
     const LangOptions &ExistingLangOpts;
     const TargetOptions &ExistingTargetOpts;
     const PreprocessorOptions &ExistingPPOpts;
+    std::string ExistingModuleCachePath;
     FileManager &FileMgr;
-    
+
   public:
     SimplePCHValidator(const LangOptions &ExistingLangOpts,
                        const TargetOptions &ExistingTargetOpts,
                        const PreprocessorOptions &ExistingPPOpts,
+                       StringRef ExistingModuleCachePath,
                        FileManager &FileMgr)
       : ExistingLangOpts(ExistingLangOpts),
         ExistingTargetOpts(ExistingTargetOpts),
         ExistingPPOpts(ExistingPPOpts),
+        ExistingModuleCachePath(ExistingModuleCachePath),
         FileMgr(FileMgr)
     {
     }
@@ -4214,6 +4250,13 @@ namespace {
                            bool Complain) override {
       return checkTargetOptions(ExistingTargetOpts, TargetOpts, nullptr);
     }
+    bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
+                                 StringRef SpecificModuleCachePath,
+                                 bool Complain) override {
+      return checkHeaderSearchOptions(HSOpts, SpecificModuleCachePath,
+                                      ExistingModuleCachePath,
+                                      nullptr, ExistingLangOpts);
+    }
     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
                                  bool Complain,
                                  std::string &SuggestedPredefines) override {
@@ -4408,8 +4451,10 @@ bool ASTReader::isAcceptableASTFile(StringRef Filename,
                                     FileManager &FileMgr,
                                     const LangOptions &LangOpts,
                                     const TargetOptions &TargetOpts,
-                                    const PreprocessorOptions &PPOpts) {
-  SimplePCHValidator validator(LangOpts, TargetOpts, PPOpts, FileMgr);
+                                    const PreprocessorOptions &PPOpts,
+                                    std::string ExistingModuleCachePath) {
+  SimplePCHValidator validator(LangOpts, TargetOpts, PPOpts,
+                               ExistingModuleCachePath, FileMgr);
   return !readASTFileControlBlock(Filename, FileMgr, validator);
 }
 
@@ -4780,8 +4825,10 @@ bool ASTReader::ParseHeaderSearchOptions(const RecordData &Record,
   HSOpts.UseStandardSystemIncludes = Record[Idx++];
   HSOpts.UseStandardCXXIncludes = Record[Idx++];
   HSOpts.UseLibcxx = Record[Idx++];
+  std::string SpecificModuleCachePath = ReadString(Record, Idx);
 
-  return Listener.ReadHeaderSearchOptions(HSOpts, Complain);
+  return Listener.ReadHeaderSearchOptions(HSOpts, SpecificModuleCachePath,
+                                          Complain);
 }
 
 bool ASTReader::ParsePreprocessorOptions(const RecordData &Record,