[committed] libstdc++: Fix std::tr2::dynamic_bitset support for alternate characters

[Jonathan Wakely]

Tested x86_64-linux. Pushed to trunk. Backports to follow.

-- >8 --

libstdc++-v3/ChangeLog:

        * include/tr2/dynamic_bitset (dynamic_bitset): Pass zero and one
        characters to _M_copy_from_string.
        * testsuite/tr2/dynamic_bitset/string.cc: New test.
---
 libstdc++-v3/include/tr2/dynamic_bitset       |  2 +-
 .../testsuite/tr2/dynamic_bitset/string.cc    | 36 +++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)
 create mode 100644 libstdc++-v3/testsuite/tr2/dynamic_bitset/string.cc

diff --git a/libstdc++-v3/include/tr2/dynamic_bitset 
b/libstdc++-v3/include/tr2/dynamic_bitset
index dd2845bd26b..ffdce82590f 100644
--- a/libstdc++-v3/include/tr2/dynamic_bitset
+++ b/libstdc++-v3/include/tr2/dynamic_bitset
@@ -622,7 +622,7 @@ namespace tr2
          // Watch for npos.
          this->_M_Nb = (__n > __str.size() ? __str.size() - __pos : __n);
          this->resize(this->_M_Nb);
-         this->_M_copy_from_string(__str, __pos, __n);
+         this->_M_copy_from_string(__str, __pos, __n, __zero, __one);
        }
 
       /**
diff --git a/libstdc++-v3/testsuite/tr2/dynamic_bitset/string.cc 
b/libstdc++-v3/testsuite/tr2/dynamic_bitset/string.cc
new file mode 100644
index 00000000000..c7d0efac35f
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr2/dynamic_bitset/string.cc
@@ -0,0 +1,36 @@
+// { dg-do run { target c++11 } }
+
+#include <tr2/dynamic_bitset>
+#include <string>
+#include <testsuite_hooks.h>
+
+void
+test_string_ctor()
+{
+  std::tr2::dynamic_bitset<> b("101001");
+  VERIFY( b[0] == true );
+  VERIFY( b[1] == false );
+  VERIFY( b[2] == false );
+  VERIFY( b[3] == true );
+  VERIFY( b[4] == false );
+  VERIFY( b[5] == true );
+}
+
+void
+test_alt_chars()
+{
+  std::string str = "xOIOIOIOx";
+  std::tr2::dynamic_bitset<> b(str, 1, 6, 'I', 'O');
+  VERIFY( b[0] == false );
+  VERIFY( b[1] == true );
+  VERIFY( b[2] == false );
+  VERIFY( b[3] == true );
+  VERIFY( b[4] == false );
+  VERIFY( b[5] == true );
+}
+
+int main()
+{
+  test_string_ctor();
+  test_alt_chars();
+}
-- 
2.42.0