[PCH] When validating that the files coming from PCH did not change, also
validate that we didn't override the contents of any of such files.
If this is detected, emit a diagnostic error and recover gracefully
by using the contents of the original file that the PCH was built from.
Part of rdar://11305263
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156107 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Basic/FileManager.cpp b/lib/Basic/FileManager.cpp
index fd6d334..669bf7d 100644
--- a/lib/Basic/FileManager.cpp
+++ b/lib/Basic/FileManager.cpp
@@ -584,6 +584,12 @@
UIDToFiles[(*VFE)->getUID()] = *VFE;
}
+void FileManager::modifyFileEntry(FileEntry *File,
+ off_t Size, time_t ModificationTime) {
+ File->Size = Size;
+ File->ModTime = ModificationTime;
+}
+
void FileManager::PrintStats() const {
llvm::errs() << "\n*** File Manager Stats:\n";
diff --git a/lib/Basic/SourceManager.cpp b/lib/Basic/SourceManager.cpp
index cef091c..ed920eb 100644
--- a/lib/Basic/SourceManager.cpp
+++ b/lib/Basic/SourceManager.cpp
@@ -71,7 +71,7 @@
void ContentCache::replaceBuffer(const llvm::MemoryBuffer *B,
bool DoNotFree) {
- if (B == Buffer.getPointer()) {
+ if (B && B == Buffer.getPointer()) {
assert(0 && "Replacing with the same buffer");
Buffer.setInt(DoNotFree? DoNotFreeFlag : 0);
return;
@@ -440,16 +440,20 @@
EntryAlign = std::max(8U, EntryAlign);
Entry = ContentCacheAlloc.Allocate<ContentCache>(1, EntryAlign);
- // If the file contents are overridden with contents from another file,
- // pass that file to ContentCache.
- llvm::DenseMap<const FileEntry *, const FileEntry *>::iterator
- overI = OverriddenFiles.find(FileEnt);
- if (overI == OverriddenFiles.end())
+ if (OverriddenFilesInfo) {
+ // If the file contents are overridden with contents from another file,
+ // pass that file to ContentCache.
+ llvm::DenseMap<const FileEntry *, const FileEntry *>::iterator
+ overI = OverriddenFilesInfo->OverriddenFiles.find(FileEnt);
+ if (overI == OverriddenFilesInfo->OverriddenFiles.end())
+ new (Entry) ContentCache(FileEnt);
+ else
+ new (Entry) ContentCache(OverridenFilesKeepOriginalName ? FileEnt
+ : overI->second,
+ overI->second);
+ } else {
new (Entry) ContentCache(FileEnt);
- else
- new (Entry) ContentCache(OverridenFilesKeepOriginalName ? FileEnt
- : overI->second,
- overI->second);
+ }
return Entry;
}
@@ -622,6 +626,8 @@
const_cast<SrcMgr::ContentCache *>(IR)->replaceBuffer(Buffer, DoNotFree);
const_cast<SrcMgr::ContentCache *>(IR)->BufferOverridden = true;
+
+ getOverriddenFilesInfo().OverriddenFilesWithBuffer.insert(SourceFile);
}
void SourceManager::overrideFileContents(const FileEntry *SourceFile,
@@ -632,7 +638,20 @@
assert(FileInfos.count(SourceFile) == 0 &&
"This function should be called at the initialization stage, before "
"any parsing occurs.");
- OverriddenFiles[SourceFile] = NewFile;
+ getOverriddenFilesInfo().OverriddenFiles[SourceFile] = NewFile;
+}
+
+void SourceManager::disableFileContentsOverride(const FileEntry *File) {
+ if (!isFileOverridden(File))
+ return;
+
+ const SrcMgr::ContentCache *IR = getOrCreateContentCache(File);
+ const_cast<SrcMgr::ContentCache *>(IR)->replaceBuffer(0);
+ const_cast<SrcMgr::ContentCache *>(IR)->ContentsEntry = IR->OrigEntry;
+
+ assert(OverriddenFilesInfo);
+ OverriddenFilesInfo->OverriddenFiles.erase(File);
+ OverriddenFilesInfo->OverriddenFilesWithBuffer.erase(File);
}
StringRef SourceManager::getBufferData(FileID FID, bool *Invalid) const {
@@ -1887,10 +1906,14 @@
}
size_t SourceManager::getDataStructureSizes() const {
- return llvm::capacity_in_bytes(MemBufferInfos)
+ size_t size = llvm::capacity_in_bytes(MemBufferInfos)
+ llvm::capacity_in_bytes(LocalSLocEntryTable)
+ llvm::capacity_in_bytes(LoadedSLocEntryTable)
+ llvm::capacity_in_bytes(SLocEntryLoaded)
- + llvm::capacity_in_bytes(FileInfos)
- + llvm::capacity_in_bytes(OverriddenFiles);
+ + llvm::capacity_in_bytes(FileInfos);
+
+ if (OverriddenFilesInfo)
+ size += llvm::capacity_in_bytes(OverriddenFilesInfo->OverriddenFiles);
+
+ return size;
}
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index f224056..f1ea091 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -2473,6 +2473,26 @@
Error("source location entry is incorrect");
return Failure;
}
+
+ off_t StoredSize = (off_t)Record[4];
+ time_t StoredTime = (time_t)Record[5];
+
+ // Check if there was a request to override the contents of the file
+ // that was part of the precompiled header. Overridding such a file
+ // can lead to problems when lexing using the source locations from the
+ // PCH.
+ SourceManager &SM = getSourceManager();
+ if (SM.isFileOverridden(File)) {
+ Error(diag::err_fe_pch_file_overridden, Filename);
+ // After emitting the diagnostic, recover by disabling the override so
+ // that the original file will be used.
+ SM.disableFileContentsOverride(File);
+ // The FileEntry is a virtual file entry with the size of the contents
+ // that would override the original contents. Set it to the original's
+ // size/time.
+ FileMgr.modifyFileEntry(const_cast<FileEntry*>(File),
+ StoredSize, StoredTime);
+ }
// The stat info from the FileEntry came from the cached stat
// info of the PCH, so we cannot trust it.
@@ -2482,12 +2502,12 @@
StatBuf.st_mtime = File->getModificationTime();
}
- if (((off_t)Record[4] != StatBuf.st_size
+ if ((StoredSize != StatBuf.st_size
#if !defined(LLVM_ON_WIN32)
// In our regression testing, the Windows file system seems to
// have inconsistent modification times that sometimes
// erroneously trigger this error-handling path.
- || (time_t)Record[5] != StatBuf.st_mtime
+ || StoredTime != StatBuf.st_mtime
#endif
)) {
Error(diag::err_fe_pch_file_modified, Filename);