commit bcf972c0208490b0eb3ce3c170c2db486ba945b3
author Chris Wailes <chriswailes@google.com> Thu Oct 21 11:03:28 2021 -0700
committer Chris Wailes <chriswailes@google.com> Thu Oct 21 11:09:35 2021 -0700
tree b1c1dbb1b4ab51d68cdf0d952fd8b6df20856cbd
parent 54272acac043c1dedfb7db7420545b31ec1ac51f

Importing rustc-1.56.0

Change-Id: I98941481270706fa55f8fb2cb91686ae3bd30f38

src/llvm-project/clang/lib/Basic/FileManager.cpp

diff --git a/src/llvm-project/clang/lib/Basic/FileManager.cpp b/src/llvm-project/clang/lib/Basic/FileManager.cpp
index 6e9d5d7..74cd2f2 100644
--- a/src/llvm-project/clang/lib/Basic/FileManager.cpp
+++ b/src/llvm-project/clang/lib/Basic/FileManager.cpp
@@ -128,7 +128,7 @@
   // Stat("C:") does not recognize "C:" as a valid directory
   std::string DirNameStr;
   if (DirName.size() > 1 && DirName.back() == ':' &&
-      DirName.equals_lower(llvm::sys::path::root_name(DirName))) {
+      DirName.equals_insensitive(llvm::sys::path::root_name(DirName))) {
     DirNameStr = DirName.str() + '.';
     DirName = DirNameStr;
   }
@@ -384,9 +384,12 @@
 
   // Now that all ancestors of Filename are in the cache, the
   // following call is guaranteed to find the DirectoryEntry from the
-  // cache.
-  auto DirInfo = expectedToOptional(
-      getDirectoryFromFile(*this, Filename, /*CacheFailure=*/true));
+  // cache. A virtual file can also have an empty filename, that could come
+  // from a source location preprocessor directive with an empty filename as
+  // an example, so we need to pretend it has a name to ensure a valid directory
+  // entry can be returned.
+  auto DirInfo = expectedToOptional(getDirectoryFromFile(
+      *this, Filename.empty() ? "." : Filename, /*CacheFailure=*/true));
   assert(DirInfo &&
          "The directory of a virtual file should already be in the cache.");
 
@@ -608,7 +611,7 @@
 
   SmallString<4096> CanonicalNameBuf;
   if (!FS->getRealPath(Dir->getName(), CanonicalNameBuf))
-    CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
+    CanonicalName = CanonicalNameBuf.str().copy(CanonicalNameStorage);
 
   CanonicalNames.insert({Dir, CanonicalName});
   return CanonicalName;
@@ -624,7 +627,7 @@
 
   SmallString<4096> CanonicalNameBuf;
   if (!FS->getRealPath(File->getName(), CanonicalNameBuf))
-    CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
+    CanonicalName = CanonicalNameBuf.str().copy(CanonicalNameStorage);
 
   CanonicalNames.insert({File, CanonicalName});
   return CanonicalName;