[clang-doc] Fix typedef/using output.

Provides an initializer for the TypedefInfo.IsUsing member. Previously
this member was uninitialized and would produce random output.

Adds the Description (code comments) to the bitcode reader/writer.
Previously the typedef/using descriptions were lost during the bitcode
round-trip. Adds a test for this.

Differential Revision: https://reviews.llvm.org/D136638

1 files changed, 9 insertions, 10 deletions

diff --git a/clang-tools-extra/clang-doc/BitcodeReader.cpp b/clang-tools-extra/clang-doc/BitcodeReader.cpp
index 8e1db35..524b82d 100644
--- a/clang-tools-extra/clang-doc/BitcodeReader.cpp
+++ b/clang-tools-extra/clang-doc/BitcodeReader.cpp
@@ -368,28 +368,27 @@ template <typename T> llvm::Expected<CommentInfo *> getCommentInfo(T I) {
 }
 
 template <> llvm::Expected<CommentInfo *> getCommentInfo(FunctionInfo *I) {
-  I->Description.emplace_back();
-  return &I->Description.back();
+  return &I->Description.emplace_back();
 }
 
 template <> llvm::Expected<CommentInfo *> getCommentInfo(NamespaceInfo *I) {
-  I->Description.emplace_back();
-  return &I->Description.back();
+  return &I->Description.emplace_back();
 }
 
 template <> llvm::Expected<CommentInfo *> getCommentInfo(RecordInfo *I) {
-  I->Description.emplace_back();
-  return &I->Description.back();
+  return &I->Description.emplace_back();
 }
 
 template <> llvm::Expected<CommentInfo *> getCommentInfo(MemberTypeInfo *I) {
-  I->Description.emplace_back();
-  return &I->Description.back();
+  return &I->Description.emplace_back();
 }
 
 template <> llvm::Expected<CommentInfo *> getCommentInfo(EnumInfo *I) {
-  I->Description.emplace_back();
-  return &I->Description.back();
+  return &I->Description.emplace_back();
+}
+
+template <> llvm::Expected<CommentInfo *> getCommentInfo(TypedefInfo *I) {
+  return &I->Description.emplace_back();
 }
 
 template <> llvm::Expected<CommentInfo *> getCommentInfo(CommentInfo *I) {