diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -3246,6 +3246,12 @@
   };
   if (Right.Tok.getIdentifierInfo() && Left.Tok.getIdentifierInfo())
     return true; // Never ever merge two identifiers.
+
+  // Leave a space between * and /* to avoid C4138 `comment end` found outside
+  // of comment.
+  if (Left.is(tok::star) && Right.is(tok::comment))
+    return true;
+
   if (Style.isCpp()) {
     if (Left.is(tok::kw_operator))
       return Right.is(tok::coloncolon);
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -9439,6 +9439,13 @@
   verifyFormat("void f() { &(*I).first; }");
 
   verifyIndependentOfContext("f(b * /* confusing comment */ ++c);");
+  verifyFormat("f(* /* confusing comment */ foo);");
+  verifyFormat("void (* /*deleter*/)(const Slice &key, void *value)");
+  verifyFormat("void foo(int * // this is the first paramters\n"
+               "         ,\n"
+               "         int second);");
+  verifyFormat("double term = a * // first\n"
+               "              b;");
   verifyFormat(
       "int *MyValues = {\n"
       "    *A, // Operator detection might be confused by the '{'\n"