Bill Fisher: This patch fixes a bug where regex_iterator doesn't indicate when it's restarting in the middle of a string. This bug causes /^a/ to match in the middle of the string "aaaaaaa", during iteration.
My patch uses to communicate when is false.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185950 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/regex b/include/regex
index 312ca11..36d5677 100644
--- a/include/regex
+++ b/include/regex
@@ -5773,7 +5773,8 @@
{
__m.__init(1 + mark_count(), __first, __last,
__flags & regex_constants::__no_update_pos);
- if (__match_at_start(__first, __last, __m, __flags, true))
+ if (__match_at_start(__first, __last, __m, __flags,
+ !(__flags & regex_constants::__no_update_pos)))
{
__m.__prefix_.second = __m[0].first;
__m.__prefix_.matched = __m.__prefix_.first != __m.__prefix_.second;
diff --git a/test/re/re.alg/re.alg.search/no_update_pos.pass.cpp b/test/re/re.alg/re.alg.search/no_update_pos.pass.cpp
new file mode 100644
index 0000000..63fcdaf
--- /dev/null
+++ b/test/re/re.alg/re.alg.search/no_update_pos.pass.cpp
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// 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.
+//
+//===----------------------------------------------------------------------===//
+
+// <regex>
+
+// template <class BidirectionalIterator, class Allocator, class charT, class traits>
+// bool
+// regex_search(BidirectionalIterator first, BidirectionalIterator last,
+// match_results<BidirectionalIterator, Allocator>& m,
+// const basic_regex<charT, traits>& e,
+// regex_constants::match_flag_type flags = regex_constants::match_default);
+
+#include <regex>
+#include <cassert>
+
+int main()
+{
+ // Iterating over /^a/ should yield one instance at the beginning
+ // of the text.
+
+ const char *text = "aaa\naa";
+ std::regex re{"^a"};
+ std::cregex_iterator it{text, text+6, re};
+ std::cregex_iterator end{};
+
+ assert(it->str() == "a");
+ assert(it->position(0) == 0);
+ assert(it->length(0) == 1);
+
+ ++it;
+ assert(it == end);
+}