diff --git a/include/boost/regex/v4/basic_regex_parser.hpp b/include/boost/regex/v4/basic_regex_parser.hpp
index 58096783..57f4c26e 100644
--- a/include/boost/regex/v4/basic_regex_parser.hpp
+++ b/include/boost/regex/v4/basic_regex_parser.hpp
@@ -1124,6 +1124,9 @@ bool basic_regex_parser<charT, traits>::parse_repeat(std::size_t low, std::size_
                   }
                   else
                      contin = false;
+                  break;
+               default:
+                  contin = false;
                }
             }
             else
diff --git a/include/boost/regex/v5/basic_regex_parser.hpp b/include/boost/regex/v5/basic_regex_parser.hpp
index 858eb805..11d581d9 100644
--- a/include/boost/regex/v5/basic_regex_parser.hpp
+++ b/include/boost/regex/v5/basic_regex_parser.hpp
@@ -1098,6 +1098,9 @@ bool basic_regex_parser<charT, traits>::parse_repeat(std::size_t low, std::size_
                   }
                   else
                      contin = false;
+                  break;
+               default:
+                  contin = false;
                }
             }
             else
diff --git a/test/regress/test_perl_ex.cpp b/test/regress/test_perl_ex.cpp
index 2a7310cd..7f47ecc2 100644
--- a/test/regress/test_perl_ex.cpp
+++ b/test/regress/test_perl_ex.cpp
@@ -58,6 +58,8 @@ void test_independent_subs()
    TEST_REGEX_SEARCH("word (?>[a-zA-Z0-9]+ ){0,30}otherword", perl, "word cat dog elephant mussel cow horse canary baboon snake shark the quick brown fox and the lazy dog and several other words getting close to thirty by now I really really hope otherword", match_default, make_array(-2, -2));
    TEST_REGEX_SEARCH("((?>Z)+|A)+", perl, "ZABCDEFG", match_default, make_array(0, 2, 1, 2, -2, -2));
    TEST_INVALID_REGEX("((?>)+|A)+", perl);
+   // Bug https://github.com/boostorg/regex/issues/140:
+   TEST_REGEX_SEARCH("1?+(?#)1", perl, "22113", match_default, make_array(2, 4, -2, -2));
 }
 
 void test_conditionals()