diff --git a/include/sta/ConcreteLibrary.hh b/include/sta/ConcreteLibrary.hh
index 5b5ed813..d4eb6ff8 100644
--- a/include/sta/ConcreteLibrary.hh
+++ b/include/sta/ConcreteLibrary.hh
@@ -196,6 +196,9 @@ public:
   // Bundles are groups of related ports that do not use
   // bus notation.
   bool isBundle() const { return is_bundle_; }
+  ConcretePort *bundlePort() const { return bundle_port_; }
+  bool isBundleMember() const { return bundle_port_ != nullptr; }
+  void setBundlePort(ConcretePort *port);
   bool isBus() const { return is_bus_; }
   // Index of cell bit ports.
   // Bus/bundle ports do not have an pin index.
@@ -251,6 +254,7 @@ protected:
   // Expanded bus bit ports (ordered by from_index_ to to_index_)
   // or bundle member ports.
   ConcretePortSeq *member_ports_;
+  ConcretePort *bundle_port_;
 
 private:
   friend class ConcreteCell;
diff --git a/include/sta/InternalPower.hh b/include/sta/InternalPower.hh
index 1ca4bf2e..0c30a38d 100644
--- a/include/sta/InternalPower.hh
+++ b/include/sta/InternalPower.hh
@@ -39,7 +39,7 @@ public:
   virtual ~InternalPowerAttrs();
   void deleteContents();
   FuncExpr *when() const { return when_; }
-  FuncExpr *&whenRef() { return when_; }
+  void setWhen(FuncExpr *when);
   void setModel(const RiseFall *rf,
 		InternalPowerModel *model);
   InternalPowerModel *model(const RiseFall *rf) const;
diff --git a/include/sta/LeakagePower.hh b/include/sta/LeakagePower.hh
index 6670a356..a0dbd86d 100644
--- a/include/sta/LeakagePower.hh
+++ b/include/sta/LeakagePower.hh
@@ -35,7 +35,7 @@ class LeakagePowerAttrs
 public:
   LeakagePowerAttrs();
   FuncExpr *when() const { return when_; }
-  FuncExpr *&whenRef() { return when_; }
+  void setWhen(FuncExpr *when);
   float power() { return power_; }
   void setPower(float power);
 
diff --git a/include/sta/Liberty.hh b/include/sta/Liberty.hh
index fec901fa..4794c30e 100644
--- a/include/sta/Liberty.hh
+++ b/include/sta/Liberty.hh
@@ -701,6 +701,7 @@ public:
   LibertyLibrary *libertyLibrary() const { return liberty_cell_->libertyLibrary(); }
   LibertyPort *findLibertyMember(int index) const;
   LibertyPort *findLibertyBusBit(int index) const;
+  LibertyPort *bundlePort() const;
   BusDcl *busDcl() const { return bus_dcl_; }
   void setDirection(PortDirection *dir);
   ScanSignalType scanSignalType() const { return scan_signal_type_; }
@@ -740,11 +741,9 @@ public:
                           const StaState *sta) const;
   FuncExpr *function() const { return function_; }
   void setFunction(FuncExpr *func);
-  FuncExpr *&functionRef() { return function_; }
   // Tristate enable function.
   FuncExpr *tristateEnable() const { return tristate_enable_; }
   void setTristateEnable(FuncExpr *enable);
-  FuncExpr *&tristateEnableRef() { return tristate_enable_; }
   void slewLimit(const MinMax *min_max,
 		 // Return values.
 		 float &limit,
@@ -1046,7 +1045,7 @@ public:
   ~ModeValueDef();
   const char *value() const { return value_.c_str(); }
   FuncExpr *cond() const { return cond_; }
-  FuncExpr *&condRef() { return cond_; }
+  void setCond(FuncExpr *cond);
   const char *sdfCond() const { return sdf_cond_.c_str(); }
   void setSdfCond(const char *sdf_cond);
 
diff --git a/include/sta/TimingArc.hh b/include/sta/TimingArc.hh
index 21e56c95..3884cbd3 100644
--- a/include/sta/TimingArc.hh
+++ b/include/sta/TimingArc.hh
@@ -104,7 +104,7 @@ public:
   TimingSense timingSense() const { return timing_sense_; }
   void setTimingSense(TimingSense sense);
   FuncExpr *cond() const { return cond_; }
-  FuncExpr *&condRef() { return cond_; }
+  void setCond(FuncExpr *cond);
   const char *sdfCond() const { return sdf_cond_; }
   void setSdfCond(const char *cond);
   const char *sdfCondStart() const { return sdf_cond_start_; }
diff --git a/liberty/InternalPower.cc b/liberty/InternalPower.cc
index a4a90740..a68dd196 100644
--- a/liberty/InternalPower.cc
+++ b/liberty/InternalPower.cc
@@ -63,6 +63,12 @@ InternalPowerAttrs::model(const RiseFall *rf) const
   return models_[rf->index()];
 }
 
+void
+InternalPowerAttrs::setWhen(FuncExpr *when)
+{
+  when_ = when;
+}
+
 void
 InternalPowerAttrs::setModel(const RiseFall *rf,
 			     InternalPowerModel *model)
diff --git a/liberty/LeakagePower.cc b/liberty/LeakagePower.cc
index 5b53604b..73e4a618 100644
--- a/liberty/LeakagePower.cc
+++ b/liberty/LeakagePower.cc
@@ -36,6 +36,12 @@ LeakagePowerAttrs::LeakagePowerAttrs() :
 {
 }
 
+void
+LeakagePowerAttrs::setWhen(FuncExpr *when)
+{
+  when_ = when;
+}
+
 void
 LeakagePowerAttrs::setPower(float power)
 {
diff --git a/liberty/Liberty.cc b/liberty/Liberty.cc
index f8cab012..ba38c6ce 100644
--- a/liberty/Liberty.cc
+++ b/liberty/Liberty.cc
@@ -2179,6 +2179,12 @@ LibertyPort::findLibertyBusBit(int index) const
   return static_cast<LibertyPort*>(findBusBit(index));
 }
 
+LibertyPort *
+LibertyPort::bundlePort() const
+{
+  return static_cast<LibertyPort*>(bundle_port_);
+}
+
 void
 LibertyPort::setCapacitance(float cap)
 {
@@ -2923,6 +2929,12 @@ ModeValueDef::~ModeValueDef()
     cond_->deleteSubexprs();
 }
 
+void
+ModeValueDef::setCond(FuncExpr *cond)
+{
+  cond_ = cond;
+}
+
 void
 ModeValueDef::setSdfCond(const char *sdf_cond)
 {
diff --git a/liberty/Liberty.i b/liberty/Liberty.i
index afa00e87..4dd5d7a8 100644
--- a/liberty/Liberty.i
+++ b/liberty/Liberty.i
@@ -310,8 +310,13 @@ LibertyCell *test_cell() { return self->testCell(); }
 const char *bus_name() { return self->busName(); }
 Cell *cell() { return self->cell(); }
 bool is_bus() { return self->isBus(); }
+bool is_bus_bit() { return self->isBusBit(); }
+bool is_bundle() { return self->isBundle(); }
+bool is_bundle_member() { return self->isBundleMember(); }
+bool has_members() { return self->hasMembers(); }
 LibertyPortMemberIterator *
 member_iterator() { return new LibertyPortMemberIterator(self); }
+LibertyPort *bundle_port() { return self->bundlePort(); }
 
 string
 function()
diff --git a/liberty/Liberty.tcl b/liberty/Liberty.tcl
index 4297683b..0103d3f5 100644
--- a/liberty/Liberty.tcl
+++ b/liberty/Liberty.tcl
@@ -50,5 +50,68 @@ proc write_liberty { args } {
   write_liberty_cmd $library $filename
 }
 
+################################################################
+
+define_cmd_args "report_lib_cell" {cell_name [> filename] [>> filename]}
+
+proc_redirect report_lib_cell {
+  check_argc_eq1 "report_lib_cell" $args
+  set arg [lindex $args 0]
+  set cell [get_lib_cell_warn "lib_cell" $arg]
+  set corner [cmd_corner]
+  if { $cell != "NULL" } {
+    report_lib_cell_ $cell $corner
+  }
+}
+
+proc report_lib_cell_ { cell corner } {
+  set lib [$cell liberty_library]
+  report_line "Cell [get_name $cell]"
+  report_line "Library [get_name $lib]"
+  set filename [liberty_cell_property $cell "filename"]
+  if { $filename != "" } {
+    report_line "File $filename"
+  }
+  set iter [$cell liberty_port_iterator]
+  while {[$iter has_next]} {
+    set port [$iter next]
+    if { [$port is_bus] || [$port is_bundle] } {
+      report_lib_port $port $corner
+      set member_iter [$port member_iterator]
+      while { [$member_iter has_next] } {
+        set port [$member_iter next]
+        report_lib_port $port $corner
+      }
+      $member_iter finish
+    } elseif { ![$port is_bundle_member] && ![$port is_bus_bit] } {
+      report_lib_port $port $corner
+    }
+  }
+  $iter finish
+}
+
+proc report_lib_port { port corner } {
+  global sta_report_default_digits
+
+  if { [$port is_bus] } {
+    set port_name [$port bus_name]
+  } else {
+    set port_name [get_name $port]
+  }
+  set indent ""
+  if { [$port is_bundle_member] || [$port is_bus_bit] } {
+    set indent "  "
+  }
+  set enable [$port tristate_enable]
+  if { $enable != "" } {
+    set enable " enable=$enable"
+  }
+  set func [$port function]
+  if { $func != "" } {
+    set func " function=$func"
+  }
+  report_line " ${indent}$port_name [liberty_port_direction $port]$enable$func[port_capacitance_str $port $corner $sta_report_default_digits]"
+}
+
 # sta namespace end
 }
diff --git a/liberty/LibertyBuilder.cc b/liberty/LibertyBuilder.cc
index 2d4b4a70..e5184345 100644
--- a/liberty/LibertyBuilder.cc
+++ b/liberty/LibertyBuilder.cc
@@ -135,6 +135,8 @@ LibertyBuilder::makeBundlePort(LibertyCell *cell,
 {
   LibertyPort *port = new LibertyPort(cell, name, false, nullptr, -1, -1, true, members);
   cell->addPort(port);
+  for (ConcretePort *member : *members)
+    member->setBundlePort(port);
   return port;
 }
 
diff --git a/liberty/LibertyReader.cc b/liberty/LibertyReader.cc
index 5e86b347..672fb1c9 100644
--- a/liberty/LibertyReader.cc
+++ b/liberty/LibertyReader.cc
@@ -2224,13 +2224,13 @@ LibertyReader::makeLeakagePowers()
 // the cell definition when all of the ports are defined.
 void
 LibertyReader::makeLibertyFunc(const char *expr,
-			       FuncExpr *&func_ref,
+                               LibertySetFunc set_func,
 			       bool invert,
 			       const char *attr_name,
 			       LibertyStmt *stmt)
 {
-  LibertyFunc *func = new LibertyFunc(expr, func_ref, invert, attr_name,
-				      stmt->line());
+  LibertyFunc *func = new LibertyFunc(expr, set_func,
+                                      invert, attr_name, stmt->line());
   cell_funcs_.push_back(func);
 }
 
@@ -2248,12 +2248,8 @@ LibertyReader::parseCellFuncs()
       else
 	expr = FuncExpr::makeNot(expr);
     }
-    if (expr) {
-      FuncExpr *prev_func = func->funcRef(); 
-      if (prev_func)
-        prev_func->deleteSubexprs();
-      func->funcRef() = expr;
-    }
+    if (expr)
+      func->setFunc()(expr);
     delete func;
   }
   cell_funcs_.clear();
@@ -3457,7 +3453,9 @@ LibertyReader::visitFunction(LibertyAttr *attr)
     const char *func = getAttrString(attr);
     if (func) {
       for (LibertyPort *port : *ports_)
-        makeLibertyFunc(func, port->functionRef(), false, "function", attr);
+        makeLibertyFunc(func,
+                        [port] (FuncExpr *expr) { port->setFunction(expr); },
+                        false, "function", attr);
     }
   }
 }
@@ -3469,8 +3467,9 @@ LibertyReader::visitThreeState(LibertyAttr *attr)
     const char *three_state = getAttrString(attr);
     if (three_state) {
       for (LibertyPort *port : *ports_)
-	makeLibertyFunc(three_state, port->tristateEnableRef(), true,
-			"three_state", attr);
+	makeLibertyFunc(three_state,
+                        [port] (FuncExpr *expr) { port->setTristateEnable(expr); },
+                        true, "three_state", attr);
     }
   }
 }
@@ -4914,23 +4913,39 @@ LibertyReader::visitWhen(LibertyAttr *attr)
     libWarn(1265, attr, "when attribute inside table model.");
   if (mode_value_) {
     const char *func = getAttrString(attr);
-    if (func)
-      makeLibertyFunc(func, mode_value_->condRef(), false, "when", attr);
+    if (func) {
+      ModeValueDef *mode_value = mode_value_;
+      makeLibertyFunc(func,
+                      [mode_value] (FuncExpr *expr) {mode_value->setCond(expr);},
+                      false, "when", attr);
+    }
   }
   if (timing_) {
     const char *func = getAttrString(attr);
-    if (func)
-      makeLibertyFunc(func, timing_->attrs()->condRef(), false, "when", attr);
+    if (func) {
+      TimingArcAttrs *attrs = timing_->attrs().get();
+      makeLibertyFunc(func,
+                      [attrs] (FuncExpr *expr) { attrs->setCond(expr);},
+                      false, "when", attr);
+    }
   }
   if (internal_power_) {
     const char *func = getAttrString(attr);
-    if (func)
-      makeLibertyFunc(func, internal_power_->whenRef(), false, "when", attr);
+    if (func) {
+      InternalPowerGroup *internal_pwr = internal_power_;
+      makeLibertyFunc(func,
+                      [internal_pwr] (FuncExpr *expr) { internal_pwr->setWhen(expr);},
+                      false, "when", attr);
+    }
   }
   if (leakage_power_) {
     const char *func = getAttrString(attr);
-    if (func)
-      makeLibertyFunc(func, leakage_power_->whenRef(), false, "when", attr);
+    if (func) {
+      LeakagePowerGroup *leakage_pwr = leakage_power_;
+      makeLibertyFunc(func,
+                      [leakage_pwr] (FuncExpr *expr) { leakage_pwr->setWhen(expr);},
+                      false, "when", attr);
+    }
   }
 }
 
@@ -5719,12 +5734,12 @@ LibertyReader::endEcsmWaveform(LibertyGroup *)
 ////////////////////////////////////////////////////////////////
 
 LibertyFunc::LibertyFunc(const char *expr,
-			 FuncExpr *&func_ref,
+                         LibertySetFunc set_func,
 			 bool invert,
 			 const char *attr_name,
 			 int line) :
   expr_(stringCopy(expr)),
-  func_ref_(func_ref),
+  set_func_(set_func),
   invert_(invert),
   attr_name_(stringCopy(attr_name)),
   line_(line)
diff --git a/liberty/LibertyReaderPvt.hh b/liberty/LibertyReaderPvt.hh
index 56109653..8a4e34f7 100644
--- a/liberty/LibertyReaderPvt.hh
+++ b/liberty/LibertyReaderPvt.hh
@@ -73,6 +73,7 @@ typedef Vector<LeakagePowerGroup*> LeakagePowerGroupSeq;
 typedef void (LibertyPort::*LibertyPortBoolSetter)(bool value);
 typedef Vector<OutputWaveform*> OutputWaveformSeq;
 typedef std::vector<std::string> StdStringSeq;
+typedef std::function<void (FuncExpr *expr)> LibertySetFunc;
 
 class LibertyReader : public LibertyGroupVisitor
 {
@@ -187,7 +188,7 @@ public:
   virtual void makeLeakagePowers();
   virtual void parseCellFuncs();
   virtual void makeLibertyFunc(const char *expr,
-			       FuncExpr *&func_ref,
+                               LibertySetFunc set_func,
 			       bool invert,
 			       const char *attr_name,
 			       LibertyStmt *stmt);
@@ -697,20 +698,20 @@ class LibertyFunc
 {
 public:
   LibertyFunc(const char *expr,
-	      FuncExpr *&func_ref,
+              LibertySetFunc set_func,
 	      bool invert,
 	      const char *attr_name,
 	      int line);
   ~LibertyFunc();
   const char *expr() const { return expr_; }
-  FuncExpr *&funcRef() const { return func_ref_; }
+  LibertySetFunc setFunc() const { return set_func_; }
   bool invert() const { return invert_; }
   const char *attrName() const { return attr_name_; }
   int line() const { return line_; }
 
 protected:
   const char *expr_;
-  FuncExpr *&func_ref_;
+  LibertySetFunc set_func_;
   bool invert_;
   const char *attr_name_;
   int line_;
diff --git a/liberty/TimingArc.cc b/liberty/TimingArc.cc
index 537f0085..b03b5cc6 100644
--- a/liberty/TimingArc.cc
+++ b/liberty/TimingArc.cc
@@ -101,6 +101,12 @@ TimingArcAttrs::setTimingSense(TimingSense sense)
   timing_sense_ = sense;
 }
 
+void
+TimingArcAttrs::setCond(FuncExpr *cond)
+{
+  cond_ = cond;
+}
+
 void
 TimingArcAttrs::setSdfCond(const char *cond)
 {
diff --git a/network/ConcreteLibrary.cc b/network/ConcreteLibrary.cc
index ec897b1e..2dedc9f4 100644
--- a/network/ConcreteLibrary.cc
+++ b/network/ConcreteLibrary.cc
@@ -179,6 +179,8 @@ ConcreteCell::makeBundlePort(const char *name,
 {
   ConcretePort *port = new ConcretePort(name, false, -1, -1, true, members, this);
   addPort(port);
+  for (ConcretePort *member : *members)
+    member->setBundlePort(port);
   return port;
 }
 
@@ -427,7 +429,8 @@ ConcretePort::ConcretePort(const char *name,
   is_bus_(is_bus),
   from_index_(from_index),
   to_index_(to_index),
-  member_ports_(member_ports)
+  member_ports_(member_ports),
+  bundle_port_(nullptr)
 {
 }
 
@@ -452,6 +455,12 @@ ConcretePort::setLibertyPort(LibertyPort *port)
   liberty_port_ = port;
 }
 
+void
+ConcretePort::setBundlePort(ConcretePort *port)
+{
+  bundle_port_ = port;
+}
+
 void
 ConcretePort::setExtPort(void *port)
 {
diff --git a/network/Network.tcl b/network/Network.tcl
index 7a05760e..b9d958a6 100644
--- a/network/Network.tcl
+++ b/network/Network.tcl
@@ -140,51 +140,6 @@ proc instance_sorted_children { instance } {
 
 ################################################################
 
-define_cmd_args "report_lib_cell" {cell_name [> filename] [>> filename]}
-
-proc_redirect report_lib_cell {
-  check_argc_eq1 "report_lib_cell" $args
-  set arg [lindex $args 0]
-  set cell [get_lib_cell_warn "lib_cell" $arg]
-  set corner [cmd_corner]
-  if { $cell != "NULL" } {
-    report_lib_cell_ $cell $corner
-  }
-}
-
-proc report_lib_cell_ { cell corner } {
-  global sta_report_default_digits
-
-  set lib [$cell liberty_library]
-  report_line "Cell [get_name $cell]"
-  report_line "Library [get_name $lib]"
-  set filename [liberty_cell_property $cell "filename"]
-  if { $filename != "" } {
-    report_line "File $filename"
-  }
-  set iter [$cell liberty_port_iterator]
-  while {[$iter has_next]} {
-    set port [$iter next]
-    if { [$port is_bus] } {
-      set port_name [$port bus_name]
-    } else {
-      set port_name [get_name $port]
-    }
-    set enable [$port tristate_enable]
-    if { $enable != "" } {
-      set enable " enable=$enable"
-    }
-    set func [$port function]
-    if { $func != "" } {
-      set func " function=$func"
-    }
-    report_line " $port_name [liberty_port_direction $port]$enable$func[port_capacitance_str $port $corner $sta_report_default_digits]"
-  }
-  $iter finish
-}
-
-################################################################
-
 define_cmd_args "report_net" {[-corner corner] [-digits digits]\
                                 net_path [> filename] [>> filename]}