[modules] Fix issue where building a module from a relative path when -working-directory option is set, results in error.

The error was "module '<name>' was built in directory '<path>' but now resides in directory '<path>'
rdar://21330027

llvm-svn: 243718

1 files changed, 14 insertions, 2 deletions

diff --git a/clang/lib/Basic/FileManager.cpp b/clang/lib/Basic/FileManager.cpp
index 4c84f1b..034ebc5 100644
--- a/clang/lib/Basic/FileManager.cpp
+++ b/clang/lib/Basic/FileManager.cpp
@@ -389,16 +389,28 @@ FileManager::getVirtualFile(StringRef Filename, off_t Size,
   return UFE;
 }
 
-void FileManager::FixupRelativePath(SmallVectorImpl<char> &path) const {
+bool FileManager::FixupRelativePath(SmallVectorImpl<char> &path) const {
   StringRef pathRef(path.data(), path.size());
 
   if (FileSystemOpts.WorkingDir.empty() 
       || llvm::sys::path::is_absolute(pathRef))
-    return;
+    return false;
 
   SmallString<128> NewPath(FileSystemOpts.WorkingDir);
   llvm::sys::path::append(NewPath, pathRef);
   path = NewPath;
+  return true;
+}
+
+bool FileManager::makeAbsolutePath(SmallVectorImpl<char> &Path) const {
+  bool Changed = FixupRelativePath(Path);
+
+  if (!llvm::sys::path::is_absolute(StringRef(Path.data(), Path.size()))) {
+    llvm::sys::fs::make_absolute(Path);
+    Changed = true;
+  }
+
+  return Changed;
 }
 
 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>