Fix bug #31387 - not checking end iterator when parsing decimal escape. Thanks to Karen for the report.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@290500 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/regex b/include/regex
index 1c4cc1d..5a6c7fb 100644
--- a/include/regex
+++ b/include/regex
@@ -4314,7 +4314,8 @@
else if ('1' <= *__first && *__first <= '9')
{
unsigned __v = *__first - '0';
- for (++__first; '0' <= *__first && *__first <= '9'; ++__first)
+ for (++__first;
+ __first != __last && '0' <= *__first && *__first <= '9'; ++__first)
__v = 10 * __v + *__first - '0';
if (__v > mark_count())
__throw_regex_error<regex_constants::error_backref>();
diff --git a/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp b/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp
new file mode 100644
index 0000000..aca4d67
--- /dev/null
+++ b/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: libcpp-no-exceptions
+// <regex>
+
+// template <class charT, class traits = regex_traits<charT>> class basic_regex;
+
+// template <class ST, class SA>
+// basic_regex(const basic_string<charT, ST, SA>& s);
+
+#include <regex>
+#include <cassert>
+#include "test_macros.h"
+
+static bool error_badbackref_thrown(const char *pat)
+{
+ bool result = false;
+ try {
+ std::regex re(pat);
+ } catch (const std::regex_error &ex) {
+ result = (ex.code() == std::regex_constants::error_backref);
+ }
+ return result;
+}
+
+int main()
+{
+ assert(error_badbackref_thrown("\\1abc")); // no references
+ assert(error_badbackref_thrown("ab(c)\\2def")); // only one reference
+
+// this should NOT throw, because we only should look at the '1'
+// See https://llvm.org/bugs/show_bug.cgi?id=31387
+ {
+ const char *pat1 = "a(b)c\\1234";
+ std::regex re(pat1, pat1 + 7); // extra chars after the end.
+ }
+}
