From b97de444717590b20b87b2fbf5f92f51d74e729e Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Sun, 9 Oct 2011 15:20:46 +0000
Subject: [PATCH] Fix <rdar://problem/10256836> getline of an empty string
 mistakenly causes failure

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@141506 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/istream                                        |  4 +++-
 .../string.io/get_line_delim.pass.cpp                  | 10 ++++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/include/istream b/include/istream
index de8aa1067..d2d37768e 100644
--- a/include/istream
+++ b/include/istream
@@ -1586,6 +1586,7 @@ getline(basic_istream<_CharT, _Traits>& __is,
         {
             __str.clear();
             ios_base::iostate __err = ios_base::goodbit;
+            streamsize __extr = 0;
             while (true)
             {
                 typename _Traits::int_type __i = __is.rdbuf()->sbumpc();
@@ -1594,6 +1595,7 @@ getline(basic_istream<_CharT, _Traits>& __is,
                    __err |= ios_base::eofbit;
                    break;
                 }
+                ++__extr;
                 _CharT __ch = _Traits::to_char_type(__i);
                 if (_Traits::eq(__ch, __dlm))
                     break;
@@ -1604,7 +1606,7 @@ getline(basic_istream<_CharT, _Traits>& __is,
                     break;
                 }
             }
-            if (__str.empty())
+            if (__extr == 0)
                __err |= ios_base::failbit;
             __is.setstate(__err);
         }
diff --git a/test/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp b/test/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp
index 656d53186..d8e2fec50 100644
--- a/test/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp
+++ b/test/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp
@@ -21,7 +21,7 @@
 int main()
 {
     {
-        std::istringstream in(" abc*  def*   ghij");
+        std::istringstream in(" abc*  def**   ghij");
         std::string s("initial text");
         getline(in, s, '*');
         assert(in.good());
@@ -30,11 +30,14 @@ int main()
         assert(in.good());
         assert(s == "  def");
         getline(in, s, '*');
+        assert(in.good());
+        assert(s == "");
+        getline(in, s, '*');
         assert(in.eof());
         assert(s == "   ghij");
     }
     {
-        std::wistringstream in(L" abc*  def*   ghij");
+        std::wistringstream in(L" abc*  def**   ghij");
         std::wstring s(L"initial text");
         getline(in, s, L'*');
         assert(in.good());
@@ -43,6 +46,9 @@ int main()
         assert(in.good());
         assert(s == L"  def");
         getline(in, s, L'*');
+        assert(in.good());
+        assert(s == L"");
+        getline(in, s, L'*');
         assert(in.eof());
         assert(s == L"   ghij");
     }