Add name offset flags, for parity with cvtres.exe.

Summary:
The original cvtres.exe sets the high bit when an identifier offset
points to a string.  Even though this is not mentioned in the spec, and
in fact does not seem to cause errors with most cases, for some reason
this causes a failure in Chromium where the new resource file is not
verified as a new version.  This patch sets this high bit flag, and also
adds a test case to check that the output of our library is always
identical to original cvtres.

Reviewers: zturner, ruiu

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D35099

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307452 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 5 insertions, 2 deletions

diff --git a/include/llvm/Object/COFF.h b/include/llvm/Object/COFF.h
index 78e0b5f6ed3..89c1ba6be35 100644
--- a/include/llvm/Object/COFF.h
+++ b/include/llvm/Object/COFF.h
@@ -698,6 +698,9 @@ struct coff_resource_dir_entry {
     uint32_t getNameOffset() const {
       return maskTrailingOnes<uint32_t>(31) & NameOffset;
     }
+    // Even though the PE/COFF spec doesn't mention this, the high bit of a name
+    // offset is set.
+    void setNameOffset(uint32_t Offset) { NameOffset = Offset | (1 << 31); }
   } Identifier;
   union {
     support::ulittle32_t DataEntryOffset;
diff --git a/lib/Object/WindowsResource.cpp b/lib/Object/WindowsResource.cpp
index b0cd6c8ebda..be767a154f9 100644
--- a/lib/Object/WindowsResource.cpp
+++ b/lib/Object/WindowsResource.cpp
@@ -616,8 +616,8 @@ void WindowsResourceCOFFWriter::writeDirectoryTree() {
     for (auto const &Child : StringChildren) {
       auto *Entry = reinterpret_cast<coff_resource_dir_entry *>(BufferStart +
                                                                 CurrentOffset);
-      Entry->Identifier.NameOffset =
-          StringTableOffsets[Child.second->getStringIndex()];
+      Entry->Identifier.setNameOffset(
+          StringTableOffsets[Child.second->getStringIndex()]);
       if (Child.second->checkIsDataNode()) {
         Entry->Offset.DataEntryOffset = NextLevelOffset;
         NextLevelOffset += sizeof(coff_resource_data_entry);