[modules] When compiling a preprocessed module map, look for headers relative

to the original module map.

Also use the path and name of the original module map when emitting that
information into the .pcm file. The upshot of this is that the produced .pcm
file will track information for headers in their original locations (where the
module was preprocessed), not relative to whatever directory the preprocessed
module map was in when it was built.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@304346 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 2 deletions

diff --git a/lib/Lex/HeaderSearch.cpp b/lib/Lex/HeaderSearch.cpp
index f5b7c59e44..9084bc352f 100644
--- a/lib/Lex/HeaderSearch.cpp
+++ b/lib/Lex/HeaderSearch.cpp
@@ -1326,14 +1326,27 @@ static const FileEntry *getPrivateModuleMap(const FileEntry *File,
 }
 
 bool HeaderSearch::loadModuleMapFile(const FileEntry *File, bool IsSystem,
-                                     FileID ID, unsigned *Offset) {
+                                     FileID ID, unsigned *Offset,
+                                     StringRef OriginalModuleMapFile) {
   // Find the directory for the module. For frameworks, that may require going
   // up from the 'Modules' directory.
   const DirectoryEntry *Dir = nullptr;
   if (getHeaderSearchOpts().ModuleMapFileHomeIsCwd)
     Dir = FileMgr.getDirectory(".");
   else {
-    Dir = File->getDir();
+    if (!OriginalModuleMapFile.empty()) {
+      // We're building a preprocessed module map. Find or invent the directory
+      // that it originally occupied.
+      Dir = FileMgr.getDirectory(
+          llvm::sys::path::parent_path(OriginalModuleMapFile));
+      if (!Dir) {
+        auto *FakeFile = FileMgr.getVirtualFile(OriginalModuleMapFile, 0, 0);
+        Dir = FakeFile->getDir();
+      }
+    } else {
+      Dir = File->getDir();
+    }
+
     StringRef DirName(Dir->getName());
     if (llvm::sys::path::filename(DirName) == "Modules") {
       DirName = llvm::sys::path::parent_path(DirName);