Implement workaround for clang 3.5 bug (#23029)

2 files changed, 76 insertions, 4 deletions

diff --git a/libbutl/sendmail.hxx b/libbutl/sendmail.hxx
index 8ff264d..8800aa5 100644
--- a/libbutl/sendmail.hxx
+++ b/libbutl/sendmail.hxx
@@ -55,25 +55,53 @@ namespace butl
     //
     using recipients_type = small_vector<std::string, 1>;
 
+    template <typename E>
+    sendmail (E&& err,
+              const std::string& from,
+              const std::string& subject,
+              const recipients_type& to);
+
+    template <typename E>
+    sendmail (E&& err,
+              const std::string& from,
+              const std::string& subject,
+              const recipients_type& to,
+              const recipients_type& cc);
+
     template <typename E, typename... O>
     sendmail (E&& err,
               const std::string& from,
               const std::string& subject,
               const recipients_type& to,
-              const recipients_type& cc = recipients_type (),
-              const recipients_type& bcc = recipients_type (),
+              const recipients_type& cc,
+              const recipients_type& bcc,
               O&&... options);
 
     // Version with the command line callback (see process_run() for details).
     //
+    template <typename C, typename E>
+    sendmail (const C&,
+              E&& err,
+              const std::string& from,
+              const std::string& subject,
+              const recipients_type& to);
+
+    template <typename C, typename E>
+    sendmail (const C&,
+              E&& err,
+              const std::string& from,
+              const std::string& subject,
+              const recipients_type& to,
+              const recipients_type& cc);
+
     template <typename C, typename E, typename... O>
     sendmail (const C&,
               E&& err,
               const std::string& from,
               const std::string& subject,
               const recipients_type& to,
-              const recipients_type& cc = recipients_type (),
-              const recipients_type& bcc = recipients_type (),
+              const recipients_type& cc,
+              const recipients_type& bcc,
               O&&... options);
 
   private:
diff --git a/libbutl/sendmail.ixx b/libbutl/sendmail.ixx
index 067153c..b88ee20 100644
--- a/libbutl/sendmail.ixx
+++ b/libbutl/sendmail.ixx
@@ -26,6 +26,27 @@ namespace butl
   {
   }
 
+  template <typename E>
+  inline sendmail::
+  sendmail (E&& err,
+            const std::string& from,
+            const std::string& subj,
+            const recipients_type& to,
+            const recipients_type& cc)
+      : sendmail (err, from, subj, to, cc, recipients_type ())
+  {
+  }
+
+  template <typename E>
+  inline sendmail::
+  sendmail (E&& err,
+            const std::string& from,
+            const std::string& subj,
+            const recipients_type& to)
+      : sendmail (err, from, subj, to, recipients_type ())
+  {
+  }
+
   template <typename C, typename E, typename... O>
   inline sendmail::
   sendmail (const C& cmdc,
@@ -65,4 +86,27 @@ namespace butl
     //
     headers (from, subj, to, cc, bcc);
   }
+
+  template <typename C, typename E>
+  inline sendmail::
+  sendmail (const C& cmdc,
+            E&& err,
+            const std::string& from,
+            const std::string& subj,
+            const recipients_type& to,
+            const recipients_type& cc)
+      : sendmail (cmdc, err, from, subj, to, cc, recipients_type ())
+  {
+  }
+
+  template <typename C, typename E>
+  inline sendmail::
+  sendmail (const C& cmdc,
+            E&& err,
+            const std::string& from,
+            const std::string& subj,
+            const recipients_type& to)
+      : sendmail (cmdc, err, from, subj, to, recipients_type ())
+  {
+  }
 }