[doc parsing]: make single character command impostures
warn in pedantic mode.

llvm-svn: 181523
diff --git a/clang/lib/AST/CommentCommandTraits.cpp b/clang/lib/AST/CommentCommandTraits.cpp
index dc4744a..6baf4a9 100644
--- a/clang/lib/AST/CommentCommandTraits.cpp
+++ b/clang/lib/AST/CommentCommandTraits.cpp
@@ -68,6 +68,11 @@
 
 const CommandInfo *
 CommandTraits::getTypoCorrectCommandInfo(StringRef Typo) const {
+  // single character command impostures, such as \t or \n must not go
+  // through the fixit logic.
+  if (Typo.size() <= 1)
+    return NULL;
+  
   SmallVector<const CommandInfo *, 2> BestCommand;
   
   int NumOfCommands = sizeof(Commands) / sizeof(CommandInfo);
diff --git a/clang/lib/AST/CommentLexer.cpp b/clang/lib/AST/CommentLexer.cpp
index c589219..b195d52 100644
--- a/clang/lib/AST/CommentLexer.cpp
+++ b/clang/lib/AST/CommentLexer.cpp
@@ -355,10 +355,6 @@
         if (!Info) {
           formTokenWithChars(T, TokenPtr, tok::unknown_command);
           T.setUnknownCommandName(CommandName);
-          // single character command impostures, such as \t or \n must not go
-          // through the fixit logic.
-          if (CommandName.size() <= 1)
-            return;
           if ((Info = Traits.getTypoCorrectCommandInfo(CommandName))) {
             StringRef CorrectedName = Info->Name;
             SourceRange CommandRange(T.getLocation().getLocWithOffset(1),
diff --git a/clang/test/Sema/warn-documentation.m b/clang/test/Sema/warn-documentation.m
index 0737a8d..14e0c34 100644
--- a/clang/test/Sema/warn-documentation.m
+++ b/clang/test/Sema/warn-documentation.m
@@ -172,3 +172,7 @@
   @struct S1 THIS IS IT
 */
 @interface S1 @end
+
+// expected-warning@+1 {{unknown command tag name}}
+/// \t bbb IS_DOXYGEN_END
+int FooBar();