clang-format: Prevent assertion discovered by fuzzer.

llvm-svn: 236578

2 files changed, 12 insertions, 2 deletions

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 39ac66b27fa..fa12d4dd7ab 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -895,8 +895,16 @@ private:
                (!Current.Previous || Current.Previous->isNot(tok::l_square))) {
       Current.Type = TT_BinaryOperator;
     } else if (Current.is(tok::comment)) {
-      Current.Type =
-          Current.TokenText.startswith("/*") ? TT_BlockComment : TT_LineComment;
+      if (Current.TokenText.startswith("/*")) {
+        if (Current.TokenText.endswith("*/"))
+          Current.Type = TT_BlockComment;
+        else
+          // The lexer has for some reason determined a comment here. But we
+          // cannot really handle it, if it isn't properly terminated.
+          Current.Tok.setKind(tok::unknown);
+      } else {
+        Current.Type = TT_LineComment;
+      }
     } else if (Current.is(tok::r_paren)) {
       if (rParenEndsCast(Current))
         Current.Type = TT_CastRParen;
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 762f92c042c..31befad6783 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -1056,6 +1056,8 @@ TEST_F(FormatTest, UnderstandsSingleLineComments) {
 
   verifyNoCrash("/\\\n/");
   verifyNoCrash("/\\\n* */");
+  // The 0-character somehow makes the lexer return a proper comment.
+  verifyNoCrash(StringRef("/*\\\0\n/", 6));
 }
 
 TEST_F(FormatTest, KeepsParameterWithTrailingCommentsOnTheirOwnLine) {