diff --git a/etc/codeTemplates/source/_Template.C b/etc/codeTemplates/source/_Template.C
index c8f231a79e..8708db0503 100644
--- a/etc/codeTemplates/source/_Template.C
+++ b/etc/codeTemplates/source/_Template.C
@@ -89,19 +89,16 @@ Foam::CLASSNAME::~CLASSNAME()
 
 void Foam::CLASSNAME::operator=(const CLASSNAME& rhs)
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 }
 
+
 // * * * * * * * * * * * * * * Friend Functions  * * * * * * * * * * * * * * //
 
-
-// * * * * * * * * * * * * * * Friend Operators * * * * * * * * * * * * * * //
+// * * * * * * * * * * * * * * * Friend Operators  * * * * * * * * * * * * * //
 
 
 // ************************************************************************* //
diff --git a/etc/codeTemplates/template/_TemplateTemplate.C b/etc/codeTemplates/template/_TemplateTemplate.C
index 9c5c3caa97..8adec14c39 100644
--- a/etc/codeTemplates/template/_TemplateTemplate.C
+++ b/etc/codeTemplates/template/_TemplateTemplate.C
@@ -102,12 +102,9 @@ void Foam::CLASSNAME<TemplateArgument>::operator=
     const CLASSNAME<TemplateArgument>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 }
 
diff --git a/src/OSspecific/POSIX/regExp/regExpPosixI.H b/src/OSspecific/POSIX/regExp/regExpPosixI.H
index 60cf6d9e5c..3d8df849af 100644
--- a/src/OSspecific/POSIX/regExp/regExpPosixI.H
+++ b/src/OSspecific/POSIX/regExp/regExpPosixI.H
@@ -126,7 +126,11 @@ inline bool Foam::regExpPosix::search(const std::string& text) const
 
 inline void Foam::regExpPosix::swap(regExpPosix& rgx)
 {
-    std::swap(preg_, rgx.preg_);
+    if (this != &rgx)
+    {
+        // Self-swap is a no-op
+        std::swap(preg_, rgx.preg_);
+    }
 }
 
 
diff --git a/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H b/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H
index 4919d62568..4fe51d14e8 100644
--- a/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H
+++ b/src/OpenFOAM/containers/Bits/PackedList/PackedListI.H
@@ -320,6 +320,7 @@ inline void Foam::PackedList<Width>::reference::operator=
     const reference& other
 )
 {
+    // Accepts self-assignment
     this->set(other.get());
 }
 
@@ -556,6 +557,11 @@ inline std::streamsize Foam::PackedList<Width>::byteSize() const
 template<unsigned Width>
 inline void Foam::PackedList<Width>::swap(PackedList<Width>& rhs)
 {
+    if (this == &rhs)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     blocks_.swap(rhs.blocks_);
     Foam::Swap(size_, rhs.size_);
 }
@@ -564,8 +570,12 @@ inline void Foam::PackedList<Width>::swap(PackedList<Width>& rhs)
 template<unsigned Width>
 inline void Foam::PackedList<Width>::transfer(PackedList<Width>& rhs)
 {
-    blocks_.transfer(rhs.blocks_);
+    if (this == &rhs)
+    {
+        return;  // Self-assignment is a no-op
+    }
 
+    blocks_.transfer(rhs.blocks_);
     size_ = rhs.size_;
     rhs.size_ = 0;
 }
diff --git a/src/OpenFOAM/containers/Bits/bitSet/bitSetI.H b/src/OpenFOAM/containers/Bits/bitSet/bitSetI.H
index 161f68c60b..c3332a4a2f 100644
--- a/src/OpenFOAM/containers/Bits/bitSet/bitSetI.H
+++ b/src/OpenFOAM/containers/Bits/bitSet/bitSetI.H
@@ -197,6 +197,7 @@ inline void Foam::bitSet::reference::operator=
     const reference& other
 )
 {
+    // Accepts self-assignment
     set(other.get());
 }
 
diff --git a/src/OpenFOAM/containers/Circulators/Circulator/CirculatorI.H b/src/OpenFOAM/containers/Circulators/Circulator/CirculatorI.H
index 9da7624c22..88aa28fe42 100644
--- a/src/OpenFOAM/containers/Circulators/Circulator/CirculatorI.H
+++ b/src/OpenFOAM/containers/Circulators/Circulator/CirculatorI.H
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2012-2015 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -170,12 +171,9 @@ void Foam::Circulator<ContainerType>::operator=
     const Circulator<ContainerType>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     begin_ = rhs.begin_;
diff --git a/src/OpenFOAM/containers/Circulators/ConstCirculator/ConstCirculatorI.H b/src/OpenFOAM/containers/Circulators/ConstCirculator/ConstCirculatorI.H
index 7c8ed24f3f..fded93cc55 100644
--- a/src/OpenFOAM/containers/Circulators/ConstCirculator/ConstCirculatorI.H
+++ b/src/OpenFOAM/containers/Circulators/ConstCirculator/ConstCirculatorI.H
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2012-2015 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -175,12 +176,9 @@ void Foam::ConstCirculator<ContainerType>::operator=
     const ConstCirculator<ContainerType>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     begin_ = rhs.begin_;
diff --git a/src/OpenFOAM/containers/Dictionaries/DictionaryBase/DictionaryBase.C b/src/OpenFOAM/containers/Dictionaries/DictionaryBase/DictionaryBase.C
index a2f73e1828..e2df5eb424 100644
--- a/src/OpenFOAM/containers/Dictionaries/DictionaryBase/DictionaryBase.C
+++ b/src/OpenFOAM/containers/Dictionaries/DictionaryBase/DictionaryBase.C
@@ -232,6 +232,11 @@ void Foam::DictionaryBase<IDLListType, T>::transfer
     DictionaryBase<IDLListType, T>& dict
 )
 {
+    if (this == &dict)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     IDLListType::transfer(dict);
     hashedTs_.transfer(dict.hashedTs_);
 }
@@ -247,9 +252,7 @@ void Foam::DictionaryBase<IDLListType, T>::operator=
 {
     if (this == &dict)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     IDLListType::operator=(dict);
diff --git a/src/OpenFOAM/containers/HashTables/HashPtrTable/HashPtrTable.C b/src/OpenFOAM/containers/HashTables/HashPtrTable/HashPtrTable.C
index 8f93c5f3d7..c8a8fffed5 100644
--- a/src/OpenFOAM/containers/HashTables/HashPtrTable/HashPtrTable.C
+++ b/src/OpenFOAM/containers/HashTables/HashPtrTable/HashPtrTable.C
@@ -149,9 +149,7 @@ void Foam::HashPtrTable<T, Key, Hash>::operator=
 {
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "attempted copy assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     this->clear();
@@ -179,9 +177,7 @@ void Foam::HashPtrTable<T, Key, Hash>::operator=
 {
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "attempted move assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     this->clear();
diff --git a/src/OpenFOAM/containers/HashTables/HashTable/HashTable.C b/src/OpenFOAM/containers/HashTables/HashTable/HashTable.C
index d2b0c45f6f..17d0121bfc 100644
--- a/src/OpenFOAM/containers/HashTables/HashTable/HashTable.C
+++ b/src/OpenFOAM/containers/HashTables/HashTable/HashTable.C
@@ -656,6 +656,11 @@ void Foam::HashTable<T, Key, Hash>::clearStorage()
 template<class T, class Key, class Hash>
 void Foam::HashTable<T, Key, Hash>::swap(HashTable<T, Key, Hash>& rhs)
 {
+    if (this == &rhs)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     Foam::Swap(size_, rhs.size_);
     Foam::Swap(capacity_, rhs.capacity_);
     Foam::Swap(table_, rhs.table_);
@@ -665,6 +670,11 @@ void Foam::HashTable<T, Key, Hash>::swap(HashTable<T, Key, Hash>& rhs)
 template<class T, class Key, class Hash>
 void Foam::HashTable<T, Key, Hash>::transfer(HashTable<T, Key, Hash>& rhs)
 {
+    if (this == &rhs)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     clear();
     swap(rhs);
 }
@@ -759,12 +769,9 @@ void Foam::HashTable<T, Key, Hash>::operator=
     const HashTable<T, Key, Hash>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (!capacity_)
@@ -813,12 +820,9 @@ void Foam::HashTable<T, Key, Hash>::operator=
     HashTable<T, Key, Hash>&& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     transfer(rhs);
diff --git a/src/OpenFOAM/containers/LinkedLists/linkTypes/DLListBase/DLListBaseI.H b/src/OpenFOAM/containers/LinkedLists/linkTypes/DLListBase/DLListBaseI.H
index 13d1d7b4d7..02cafc82b0 100644
--- a/src/OpenFOAM/containers/LinkedLists/linkTypes/DLListBase/DLListBaseI.H
+++ b/src/OpenFOAM/containers/LinkedLists/linkTypes/DLListBase/DLListBaseI.H
@@ -185,6 +185,11 @@ inline void Foam::DLListBase::clear()
 
 inline void Foam::DLListBase::swap(DLListBase& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     std::swap(first_, lst.first_);
     std::swap(last_, lst.last_);
     std::swap(size_, lst.size_);
@@ -193,6 +198,11 @@ inline void Foam::DLListBase::swap(DLListBase& lst)
 
 inline void Foam::DLListBase::transfer(DLListBase& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     first_ = lst.first_;
     last_  = lst.last_;
     size_  = lst.size_;
diff --git a/src/OpenFOAM/containers/LinkedLists/linkTypes/SLListBase/SLListBaseI.H b/src/OpenFOAM/containers/LinkedLists/linkTypes/SLListBase/SLListBaseI.H
index 42c08708c6..d9a4456521 100644
--- a/src/OpenFOAM/containers/LinkedLists/linkTypes/SLListBase/SLListBaseI.H
+++ b/src/OpenFOAM/containers/LinkedLists/linkTypes/SLListBase/SLListBaseI.H
@@ -143,6 +143,11 @@ inline void Foam::SLListBase::clear()
 
 inline void Foam::SLListBase::swap(SLListBase& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     std::swap(last_, lst.last_);
     std::swap(size_, lst.size_);
 }
@@ -150,6 +155,11 @@ inline void Foam::SLListBase::swap(SLListBase& lst)
 
 inline void Foam::SLListBase::transfer(SLListBase& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     last_ = lst.last_;
     size_ = lst.size_;
 
diff --git a/src/OpenFOAM/containers/Lists/CompactListList/CompactListList.C b/src/OpenFOAM/containers/Lists/CompactListList/CompactListList.C
index d837f41b9f..f2fbd29724 100644
--- a/src/OpenFOAM/containers/Lists/CompactListList/CompactListList.C
+++ b/src/OpenFOAM/containers/Lists/CompactListList/CompactListList.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -203,6 +204,11 @@ void Foam::CompactListList<T, Container>::swap
     CompactListList<T, Container>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     Foam::Swap(size_, lst.size_);
     offsets_.swap(lst.offsets_);
     m_.swap(lst.m_);
@@ -215,6 +221,11 @@ void Foam::CompactListList<T, Container>::transfer
     CompactListList<T, Container>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     size_ = lst.size_;
     offsets_.transfer(lst.offsets_);
     m_.transfer(lst.m_);
diff --git a/src/OpenFOAM/containers/Lists/CompactListList/CompactListListI.H b/src/OpenFOAM/containers/Lists/CompactListList/CompactListListI.H
index ff79c865be..1a3c2613ab 100644
--- a/src/OpenFOAM/containers/Lists/CompactListList/CompactListListI.H
+++ b/src/OpenFOAM/containers/Lists/CompactListList/CompactListListI.H
@@ -303,6 +303,11 @@ inline void Foam::CompactListList<T, Container>::operator=
     const CompactListList<T, Container>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     size_ = lst.size_;
     offsets_ = lst.offsets_,
     m_ = lst.m_;
@@ -315,6 +320,11 @@ inline void Foam::CompactListList<T, Container>::operator=
     CompactListList<T, Container>&& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     transfer(lst);
 }
 
diff --git a/src/OpenFOAM/containers/Lists/Distribution/Distribution.C b/src/OpenFOAM/containers/Lists/Distribution/Distribution.C
index 19b29270f9..1e5d2e541b 100644
--- a/src/OpenFOAM/containers/Lists/Distribution/Distribution.C
+++ b/src/OpenFOAM/containers/Lists/Distribution/Distribution.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -557,12 +558,9 @@ void Foam::Distribution<Type>::operator=
     const Distribution<Type>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     List<List<scalar>>::operator=(rhs);
diff --git a/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H b/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H
index d74bc281db..6b71e10211 100644
--- a/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H
+++ b/src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H
@@ -397,6 +397,11 @@ inline void Foam::DynamicList<T, SizeMin>::swap
     DynamicList<T, AnySizeMin>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     DynamicList<T, SizeMin>& cur = *this;
 
     // Make addressable size identical to the allocated capacity
@@ -434,6 +439,11 @@ Foam::DynamicList<T, SizeMin>::transfer
     DynamicList<T, AnySizeMin>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     // Take over storage as-is (without shrink, without using SizeMin)
     // clear addressing and storage for old lst.
     capacity_ = lst.capacity();
@@ -793,8 +803,7 @@ inline void Foam::DynamicList<T, SizeMin>::operator=
 {
     if (this == &lst)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self" << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     assignDynList(lst);
@@ -808,6 +817,11 @@ inline void Foam::DynamicList<T, SizeMin>::operator=
     const DynamicList<T, SizeMin2>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     assignDynList(lst);
 }
 
@@ -852,8 +866,7 @@ inline void Foam::DynamicList<T, SizeMin>::operator=
 {
     if (this == &lst)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self" << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     clear();
@@ -868,6 +881,11 @@ inline void Foam::DynamicList<T, SizeMin>::operator=
     DynamicList<T, SizeMin2>&& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     clear();
     transfer(lst);
 }
@@ -887,7 +905,11 @@ inline void Foam::DynamicList<T, SizeMin>::operator=
 // * * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * //
 
 template<class T, int SizeMin1, int SizeMin2>
-inline void Foam::Swap(DynamicList<T, SizeMin1>& a, DynamicList<T, SizeMin2>& b)
+inline void Foam::Swap
+(
+    DynamicList<T, SizeMin1>& a,
+    DynamicList<T, SizeMin2>& b
+)
 {
     a.swap(b);
 }
diff --git a/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H b/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H
index d6e5f62bc6..47057ec995 100644
--- a/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H
+++ b/src/OpenFOAM/containers/Lists/FixedList/FixedListI.H
@@ -331,6 +331,11 @@ inline void Foam::FixedList<T, N>::setSize(const label n)
 template<class T, unsigned N>
 inline void Foam::FixedList<T, N>::swap(FixedList<T, N>& list)
 {
+    if (this == &list)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     for (unsigned i=0; i<N; ++i)
     {
         Foam::Swap(v_[i], list.v_[i]);
@@ -341,6 +346,11 @@ inline void Foam::FixedList<T, N>::swap(FixedList<T, N>& list)
 template<class T, unsigned N>
 inline void Foam::FixedList<T, N>::transfer(FixedList<T, N>& list)
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     for (unsigned i=0; i<N; ++i)
     {
         v_[i] = std::move(list[i]);
@@ -428,6 +438,11 @@ inline void Foam::FixedList<T, N>::operator=(const T& val)
 template<class T, unsigned N>
 inline void Foam::FixedList<T, N>::operator=(const FixedList<T, N>& list)
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     for (unsigned i=0; i<N; ++i)
     {
         v_[i] = list.v_[i];
@@ -437,6 +452,11 @@ inline void Foam::FixedList<T, N>::operator=(const FixedList<T, N>& list)
 template<class T, unsigned N>
 inline void Foam::FixedList<T, N>::operator=(FixedList<T, N>&& list)
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     // No significant speedup observed for copy assignment on simple types,
     // use move assignment for generality with more complex types
     for (unsigned i=0; i<N; ++i)
diff --git a/src/OpenFOAM/containers/Lists/List/List.C b/src/OpenFOAM/containers/Lists/List/List.C
index d91dcc8794..426efed774 100644
--- a/src/OpenFOAM/containers/Lists/List/List.C
+++ b/src/OpenFOAM/containers/Lists/List/List.C
@@ -435,6 +435,11 @@ void Foam::List<T>::resize(const label newSize, const T& val)
 template<class T>
 void Foam::List<T>::transfer(List<T>& list)
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     // Clear and swap - could also check for self assignment
     clear();
     this->size_ = list.size_;
@@ -472,6 +477,11 @@ void Foam::List<T>::transfer(SortableList<T>& list)
 template<class T>
 void Foam::List<T>::operator=(const UList<T>& a)
 {
+    if (this == &a)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     reAlloc(a.size_);
 
     const label len = this->size_;
@@ -505,9 +515,7 @@ void Foam::List<T>::operator=(const List<T>& list)
 {
     if (this == &list)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     operator=(static_cast<const UList<T>&>(list));
@@ -581,9 +589,7 @@ void Foam::List<T>::operator=(List<T>&& list)
 {
     if (this == &list)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     transfer(list);
diff --git a/src/OpenFOAM/containers/Lists/List/ListI.H b/src/OpenFOAM/containers/Lists/List/ListI.H
index b6e2d2f990..c32eef5394 100644
--- a/src/OpenFOAM/containers/Lists/List/ListI.H
+++ b/src/OpenFOAM/containers/Lists/List/ListI.H
@@ -193,7 +193,7 @@ inline void Foam::List<T>::append(const UList<T>& list)
     if (this == &list)
     {
         FatalErrorInFunction
-            << "attempted appending to self" << abort(FatalError);
+            << "Attempted appending to self" << abort(FatalError);
     }
 
     label idx = this->size();
diff --git a/src/OpenFOAM/containers/Lists/SortableList/SortableList.C b/src/OpenFOAM/containers/Lists/SortableList/SortableList.C
index 817e9c00d0..4d3d755a2f 100644
--- a/src/OpenFOAM/containers/Lists/SortableList/SortableList.C
+++ b/src/OpenFOAM/containers/Lists/SortableList/SortableList.C
@@ -197,6 +197,11 @@ void Foam::SortableList<T>::partialReverseSort(label n, label start)
 template<class T>
 void Foam::SortableList<T>::swap(SortableList<T>& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     List<T>::swap(lst);
     indices_.swap(lst.indices_);
 }
@@ -223,6 +228,11 @@ inline void Foam::SortableList<T>::operator=(const UList<T>& lst)
 template<class T>
 inline void Foam::SortableList<T>::operator=(const SortableList<T>& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-assigment is a no-op
+    }
+
     List<T>::operator=(lst);
     indices_ = lst.indices();
 }
@@ -239,6 +249,11 @@ inline void Foam::SortableList<T>::operator=(List<T>&& lst)
 template<class T>
 inline void Foam::SortableList<T>::operator=(SortableList<T>&& lst)
 {
+    if (this == &lst)
+    {
+        return;  // Self-assigment is a no-op
+    }
+
     clear();
     this->swap(lst);
 }
diff --git a/src/OpenFOAM/containers/Lists/UList/UListI.H b/src/OpenFOAM/containers/Lists/UList/UListI.H
index 8066626e65..4a8452487f 100644
--- a/src/OpenFOAM/containers/Lists/UList/UListI.H
+++ b/src/OpenFOAM/containers/Lists/UList/UListI.H
@@ -380,6 +380,11 @@ inline bool Foam::UList<T>::empty() const noexcept
 template<class T>
 inline void Foam::UList<T>::swap(UList<T>& list)
 {
+    if (&list == this)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     Foam::Swap(size_, list.size_);
     Foam::Swap(v_, list.v_);
 }
diff --git a/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H b/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H
index b3045ad253..d6845719d8 100644
--- a/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H
+++ b/src/OpenFOAM/containers/PtrLists/PtrDynList/PtrDynListI.H
@@ -369,6 +369,11 @@ inline void Foam::PtrDynList<T, SizeMin>::operator=
     const PtrList<T>& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     PtrList<T>::operator=(list);
     capacity_ = PtrList<T>::size();
 }
@@ -380,6 +385,11 @@ inline void Foam::PtrDynList<T, SizeMin>::operator=
     const PtrDynList<T, SizeMin>& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     PtrList<T>::operator=(list);
     capacity_ = PtrList<T>::size();
 }
@@ -392,6 +402,11 @@ inline void Foam::PtrDynList<T, SizeMin>::operator=
     const PtrDynList<T, AnySizeMin>& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     PtrList<T>::operator=(list);
     capacity_ = PtrList<T>::size();
 }
@@ -403,6 +418,11 @@ inline void Foam::PtrDynList<T, SizeMin>::operator=
     PtrList<T>&& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     PtrList<T>::transfer(list);
     capacity_ = PtrList<T>::size();
     list.clearStorage();
@@ -415,6 +435,11 @@ inline void Foam::PtrDynList<T, SizeMin>::operator=
     PtrDynList<T, SizeMin>&& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     PtrList<T>::transfer(list);
     capacity_ = list.capacity();
     list.clearStorage();
@@ -428,6 +453,11 @@ inline void Foam::PtrDynList<T, SizeMin>::operator=
     PtrDynList<T, AnySizeMin>&& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     PtrList<T>::transfer(list);
     capacity_ = list.capacity();
     list.clearStorage();
diff --git a/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.C b/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.C
index b75abd5366..7df86c8da3 100644
--- a/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.C
+++ b/src/OpenFOAM/containers/PtrLists/PtrList/PtrList.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2018 OpenCFD Ltd.
+    Copyright (C) 2018-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -134,9 +134,7 @@ void Foam::PtrList<T>::operator=(const PtrList<T>& list)
 {
     if (this == &list)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self for type " << typeid(T).name()
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     const label oldLen = this->size();
diff --git a/src/OpenFOAM/containers/PtrLists/UPtrList/UPtrListI.H b/src/OpenFOAM/containers/PtrLists/UPtrList/UPtrListI.H
index 2d56f368bb..6c29a834a7 100644
--- a/src/OpenFOAM/containers/PtrLists/UPtrList/UPtrListI.H
+++ b/src/OpenFOAM/containers/PtrLists/UPtrList/UPtrListI.H
@@ -203,7 +203,7 @@ inline const T& Foam::UPtrList<T>::operator[](const label i) const
     {
         FatalErrorInFunction
             << "Cannot dereference nullptr at index " << i
-            << " in range [0," << size() << ")"
+            << " in range [0," << size() << ")\n"
             << abort(FatalError);
     }
 
@@ -220,7 +220,7 @@ inline T& Foam::UPtrList<T>::operator[](const label i)
     {
         FatalErrorInFunction
             << "Cannot dereference nullptr at index " << i
-            << " in range [0," << size() << ")"
+            << " in range [0," << size() << ")\n"
             << abort(FatalError);
     }
 
diff --git a/src/OpenFOAM/db/IOobjects/CompactIOField/CompactIOField.C b/src/OpenFOAM/db/IOobjects/CompactIOField/CompactIOField.C
index 2763bcdfb1..c7ab9b7ac9 100644
--- a/src/OpenFOAM/db/IOobjects/CompactIOField/CompactIOField.C
+++ b/src/OpenFOAM/db/IOobjects/CompactIOField/CompactIOField.C
@@ -215,6 +215,11 @@ void Foam::CompactIOField<T, BaseType>::operator=
     const CompactIOField<T, BaseType>& rhs
 )
 {
+    if (this == &rhs)
+    {
+        return;  // Self-assigment is a no-op
+    }
+
     Field<T>::operator=(rhs);
 }
 
diff --git a/src/OpenFOAM/db/IOobjects/CompactIOList/CompactIOList.C b/src/OpenFOAM/db/IOobjects/CompactIOList/CompactIOList.C
index c13cf8ccd7..cfd3507fca 100644
--- a/src/OpenFOAM/db/IOobjects/CompactIOList/CompactIOList.C
+++ b/src/OpenFOAM/db/IOobjects/CompactIOList/CompactIOList.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2015-2018 OpenCFD Ltd.
+    Copyright (C) 2015-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
diff --git a/src/OpenFOAM/db/IOstreams/token/tokenI.H b/src/OpenFOAM/db/IOstreams/token/tokenI.H
index 33885121a6..6b63aed010 100644
--- a/src/OpenFOAM/db/IOstreams/token/tokenI.H
+++ b/src/OpenFOAM/db/IOstreams/token/tokenI.H
@@ -281,6 +281,11 @@ inline void Foam::token::reset()
 
 inline void Foam::token::swap(token& tok)
 {
+    if (this == &tok)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     std::swap(data_, tok.data_);
     std::swap(type_, tok.type_);
     std::swap(lineNumber_, tok.lineNumber_);
@@ -642,6 +647,11 @@ inline void Foam::token::setBad()
 
 inline void Foam::token::operator=(const token& tok)
 {
+    if (this == &tok)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     reset();
 
     type_ = tok.type_;
@@ -683,6 +693,11 @@ inline void Foam::token::operator=(const token& tok)
 
 inline void Foam::token::operator=(token&& tok)
 {
+    if (this == &tok)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     reset();
     lineNumber_ = 0;
     swap(tok);
diff --git a/src/OpenFOAM/db/dictionary/dictionary.C b/src/OpenFOAM/db/dictionary/dictionary.C
index 10382ee816..4b07aca7fc 100644
--- a/src/OpenFOAM/db/dictionary/dictionary.C
+++ b/src/OpenFOAM/db/dictionary/dictionary.C
@@ -876,7 +876,7 @@ bool Foam::dictionary::merge(const dictionary& dict)
     if (this == &dict)
     {
         FatalIOErrorInFunction(*this)
-            << "Attempted merge to self for dictionary "
+            << "Attempted merge to self, for dictionary "
             << name() << nl
             << abort(FatalIOError);
     }
@@ -944,10 +944,7 @@ void Foam::dictionary::operator=(const dictionary& rhs)
 {
     if (this == &rhs)
     {
-        FatalIOErrorInFunction(*this)
-            << "Attempted assignment to self for dictionary "
-            << name() << nl
-            << abort(FatalIOError);
+        return;  // Self-assignment is a no-op
     }
 
     name() = rhs.name();
@@ -968,7 +965,7 @@ void Foam::dictionary::operator+=(const dictionary& rhs)
     if (this == &rhs)
     {
         FatalIOErrorInFunction(*this)
-            << "Attempted addition assignment to self for dictionary "
+            << "Attempted addition to self, for dictionary "
             << name() << nl
             << abort(FatalIOError);
     }
@@ -985,7 +982,7 @@ void Foam::dictionary::operator|=(const dictionary& rhs)
     if (this == &rhs)
     {
         FatalIOErrorInFunction(*this)
-            << "Attempted assignment to self for dictionary "
+            << "Attempted |= merging to self, for dictionary "
             << name() << nl
             << abort(FatalIOError);
     }
@@ -1005,7 +1002,7 @@ void Foam::dictionary::operator<<=(const dictionary& rhs)
     if (this == &rhs)
     {
         FatalIOErrorInFunction(*this)
-            << "Attempted assignment to self for dictionary "
+            << "Attempted addition to self, for dictionary "
             << name() << nl
             << abort(FatalIOError);
     }
diff --git a/src/OpenFOAM/db/dictionary/entry/entry.C b/src/OpenFOAM/db/dictionary/entry/entry.C
index cb065eec76..3e5fe33877 100644
--- a/src/OpenFOAM/db/dictionary/entry/entry.C
+++ b/src/OpenFOAM/db/dictionary/entry/entry.C
@@ -179,12 +179,9 @@ void Foam::entry::checkITstream(const ITstream& is) const
 
 void Foam::entry::operator=(const entry& e)
 {
-    // check for assignment to self
     if (this == &e)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     keyword_ = e.keyword_;
@@ -193,20 +190,24 @@ void Foam::entry::operator=(const entry& e)
 
 bool Foam::entry::operator==(const entry& e) const
 {
+    if (this == &e)
+    {
+        return true;
+    }
     if (keyword_ != e.keyword_)
     {
         return false;
     }
-    else
-    {
-        OStringStream oss1;
-        oss1 << *this;
 
-        OStringStream oss2;
-        oss2 << e;
+    // Compare contents (as strings)
 
-        return oss1.str() == oss2.str();
-    }
+    OStringStream oss1;
+    oss1 << *this;
+
+    OStringStream oss2;
+    oss2 << e;
+
+    return oss1.str() == oss2.str();
 }
 
 
diff --git a/src/OpenFOAM/db/objectRegistry/objectRegistry.C b/src/OpenFOAM/db/objectRegistry/objectRegistry.C
index ed32f81a8b..f6832dc47b 100644
--- a/src/OpenFOAM/db/objectRegistry/objectRegistry.C
+++ b/src/OpenFOAM/db/objectRegistry/objectRegistry.C
@@ -259,7 +259,7 @@ bool Foam::objectRegistry::checkIn(regIOobject* io) const
     if (!ok && objectRegistry::debug)
     {
         WarningInFunction
-            << name() << " : attempted to checkIn object with name "
+            << name() << " : Attempt to checkIn object with name "
             << io->name() << " which was already checked in"
             << endl;
     }
@@ -291,7 +291,7 @@ bool Foam::objectRegistry::checkOut(regIOobject* io) const
             if (objectRegistry::debug)
             {
                 WarningInFunction
-                    << name() << " : attempt to checkOut copy of "
+                    << name() << " : Attempt to checkOut copy of "
                     << iter.key()
                     << endl;
             }
diff --git a/src/OpenFOAM/fields/DimensionedFields/DimensionedField/DimensionedField.C b/src/OpenFOAM/fields/DimensionedFields/DimensionedField/DimensionedField.C
index 19f3542e67..17b50d374b 100644
--- a/src/OpenFOAM/fields/DimensionedFields/DimensionedField/DimensionedField.C
+++ b/src/OpenFOAM/fields/DimensionedFields/DimensionedField/DimensionedField.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2015-2017 OpenCFD Ltd.
+    Copyright (C) 2015-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -492,12 +492,9 @@ void Foam::DimensionedField<Type, GeoMesh>::operator=
     const DimensionedField<Type, GeoMesh>& df
 )
 {
-    // Check for assignment to self
     if (this == &df)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     checkField(*this, df, "=");
@@ -516,12 +513,9 @@ void Foam::DimensionedField<Type, GeoMesh>::operator=
 {
     auto& df = tdf.constCast();
 
-    // Check for assignment to self
     if (this == &df)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     checkField(*this, df, "=");
diff --git a/src/OpenFOAM/fields/FieldFields/FieldField/FieldField.C b/src/OpenFOAM/fields/FieldFields/FieldField/FieldField.C
index 17e38a80c9..29f4fe8c21 100644
--- a/src/OpenFOAM/fields/FieldFields/FieldField/FieldField.C
+++ b/src/OpenFOAM/fields/FieldFields/FieldField/FieldField.C
@@ -292,10 +292,9 @@ void FieldField<Field, Type>::operator=(const FieldField<Field, Type>& ff)
 {
     if (this == &ff)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
+
     // No size checking done
 
     forAll(*this, i)
@@ -310,9 +309,7 @@ void FieldField<Field, Type>::operator=(FieldField<Field, Type>&& ff)
 {
     if (this == &ff)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     PtrList<Field<Type>>::transfer(ff);
@@ -325,9 +322,7 @@ void FieldField<Field, Type>::operator=(const tmp<FieldField>& tf)
     // The cref() method also checks that tmp is not nullptr.
     if (this == &(tf.cref()))
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     PtrList<Field<Type>>::clear();
@@ -414,6 +409,6 @@ Ostream& operator<<(Ostream& os, const tmp<FieldField<Field, Type>>& tf)
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
-    #include "FieldFieldFunctions.C"
+#include "FieldFieldFunctions.C"
 
 // ************************************************************************* //
diff --git a/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H b/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H
index 53bc5b4944..114480ba1b 100644
--- a/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H
+++ b/src/OpenFOAM/fields/Fields/DynamicField/DynamicFieldI.H
@@ -399,6 +399,11 @@ inline void Foam::DynamicField<T, SizeMin>::swap
     DynamicField<T, AnySizeMin>& lst
 )
 {
+    if (this == &lst)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     DynamicList<T, SizeMin>& cur = *this;
 
     // Make addressable size identical to the allocated capacity
@@ -450,6 +455,11 @@ inline void Foam::DynamicField<T, SizeMin>::transfer
     DynamicField<T, AnySizeMin>& list
 )
 {
+    if (this == &list)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     // Take over storage as-is (without shrink, without using SizeMin)
     // clear addressing and storage for old list.
     capacity_ = list.capacity();
@@ -484,7 +494,7 @@ Foam::DynamicField<T, SizeMin>::append
     if (this == &list)
     {
         FatalErrorInFunction
-            << "attempted appending to self" << abort(FatalError);
+            << "Attempted appending to self" << abort(FatalError);
     }
 
     label idx = List<T>::size();
@@ -563,8 +573,7 @@ inline void Foam::DynamicField<T, SizeMin>::operator=
 {
     if (this == &list)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self" << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     assignDynField(list);
diff --git a/src/OpenFOAM/fields/Fields/Field/Field.C b/src/OpenFOAM/fields/Fields/Field/Field.C
index 3409578237..549b6d850f 100644
--- a/src/OpenFOAM/fields/Fields/Field/Field.C
+++ b/src/OpenFOAM/fields/Fields/Field/Field.C
@@ -656,9 +656,7 @@ void Foam::Field<Type>::operator=(const Field<Type>& rhs)
 {
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     List<Type>::operator=(rhs);
@@ -670,9 +668,7 @@ void Foam::Field<Type>::operator=(const tmp<Field>& rhs)
 {
     if (this == &(rhs()))
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     List<Type>::operator=(rhs());
diff --git a/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C b/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C
index df340d238f..1b1c486680 100644
--- a/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C
+++ b/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C
@@ -1327,9 +1327,7 @@ void Foam::GeometricField<Type, PatchField, GeoMesh>::operator=
 {
     if (this == &gf)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     checkField(*this, gf, "=");
@@ -1351,9 +1349,7 @@ void Foam::GeometricField<Type, PatchField, GeoMesh>::operator=
 
     if (this == &gf)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     checkField(*this, gf, "=");
diff --git a/src/OpenFOAM/matrices/LduMatrix/LduMatrix/LduMatrixOperations.C b/src/OpenFOAM/matrices/LduMatrix/LduMatrix/LduMatrixOperations.C
index 5521b4f03e..7524e15f06 100644
--- a/src/OpenFOAM/matrices/LduMatrix/LduMatrix/LduMatrixOperations.C
+++ b/src/OpenFOAM/matrices/LduMatrix/LduMatrix/LduMatrixOperations.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -170,9 +171,7 @@ void Foam::LduMatrix<Type, DType, LUType>::operator=(const LduMatrix& A)
 {
     if (this == &A)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (A.diagPtr_)
diff --git a/src/OpenFOAM/matrices/Matrix/Matrix.C b/src/OpenFOAM/matrices/Matrix/Matrix.C
index 94fc3ed55d..b5ea2e4519 100644
--- a/src/OpenFOAM/matrices/Matrix/Matrix.C
+++ b/src/OpenFOAM/matrices/Matrix/Matrix.C
@@ -289,6 +289,11 @@ Foam::List<Type> Foam::Matrix<Form, Type>::release()
 template<class Form, class Type>
 void Foam::Matrix<Form, Type>::swap(Matrix<Form, Type>& mat)
 {
+    if (this == &mat)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     Foam::Swap(mRows_, mat.mRows_);
     Foam::Swap(nCols_, mat.nCols_);
     Foam::Swap(v_, mat.v_);
@@ -298,6 +303,11 @@ void Foam::Matrix<Form, Type>::swap(Matrix<Form, Type>& mat)
 template<class Form, class Type>
 void Foam::Matrix<Form, Type>::transfer(Matrix<Form, Type>& mat)
 {
+    if (this == &mat)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     clear();
 
     mRows_ = mat.mRows_;
@@ -457,9 +467,7 @@ void Foam::Matrix<Form, Type>::operator=(const Matrix<Form, Type>& mat)
 {
     if (this == &mat)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (mRows_ != mat.mRows_ || nCols_ != mat.nCols_)
@@ -480,14 +488,11 @@ void Foam::Matrix<Form, Type>::operator=(const Matrix<Form, Type>& mat)
 template<class Form, class Type>
 void Foam::Matrix<Form, Type>::operator=(Matrix<Form, Type>&& mat)
 {
-    if (this == &mat)
+    if (this != &mat)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        // Self-assignment is a no-op
+        this->transfer(mat);
     }
-
-    this->transfer(mat);
 }
 
 
diff --git a/src/OpenFOAM/matrices/lduMatrix/lduMatrix/lduMatrixOperations.C b/src/OpenFOAM/matrices/lduMatrix/lduMatrix/lduMatrixOperations.C
index 915f682b53..4d307f5710 100644
--- a/src/OpenFOAM/matrices/lduMatrix/lduMatrix/lduMatrixOperations.C
+++ b/src/OpenFOAM/matrices/lduMatrix/lduMatrix/lduMatrixOperations.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -91,10 +92,7 @@ void Foam::lduMatrix::operator=(const lduMatrix& A)
 {
     if (this == &A)
     {
-        FatalError
-            << "lduMatrix::operator=(const lduMatrix&) : "
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (A.lowerPtr_)
diff --git a/src/OpenFOAM/matrices/simpleMatrix/simpleMatrix.C b/src/OpenFOAM/matrices/simpleMatrix/simpleMatrix.C
index d9d531d639..693a33ff01 100644
--- a/src/OpenFOAM/matrices/simpleMatrix/simpleMatrix.C
+++ b/src/OpenFOAM/matrices/simpleMatrix/simpleMatrix.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -103,9 +104,7 @@ void Foam::simpleMatrix<Type>::operator=(const simpleMatrix<Type>& m)
 {
     if (this == &m)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (m() != m.m())
diff --git a/src/OpenFOAM/memory/autoPtr/autoPtrI.H b/src/OpenFOAM/memory/autoPtr/autoPtrI.H
index 7b536a0fc9..ba1eb5b93e 100644
--- a/src/OpenFOAM/memory/autoPtr/autoPtrI.H
+++ b/src/OpenFOAM/memory/autoPtr/autoPtrI.H
@@ -172,6 +172,7 @@ inline void Foam::autoPtr<T>::reset(autoPtr<T>&& ap) noexcept
 template<class T>
 inline void Foam::autoPtr<T>::swap(autoPtr<T>& other) noexcept
 {
+    // Self-swap is effectively ignored
     T* p = ptr_;
     ptr_ = other.ptr_;
     other.ptr_ = p;
@@ -259,6 +260,7 @@ inline void Foam::autoPtr<T>::operator=(autoPtr<T>&& ap) noexcept
 {
     if (this != &ap)
     {
+        // Ignore self-assignment
         reset(ap.release());
     }
 }
@@ -270,6 +272,7 @@ inline void Foam::autoPtr<T>::operator=(autoPtr<U>&& ap) noexcept
 {
     if (this != &ap)
     {
+        // Ignore self-assignment
         reset(ap.release());
     }
 }
diff --git a/src/OpenFOAM/memory/tmp/tmpI.H b/src/OpenFOAM/memory/tmp/tmpI.H
index 261472c6a0..21e30caf6f 100644
--- a/src/OpenFOAM/memory/tmp/tmpI.H
+++ b/src/OpenFOAM/memory/tmp/tmpI.H
@@ -369,6 +369,11 @@ inline void Foam::tmp<T>::cref(const T& obj) noexcept
 template<class T>
 inline void Foam::tmp<T>::swap(tmp<T>& other) noexcept
 {
+    if (&other == this)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     // Copy/assign for pointer types
     T* p = ptr_;
     ptr_ = other.ptr_;
@@ -460,6 +465,11 @@ inline void Foam::tmp<T>::operator=(T* p)
 template<class T>
 inline void Foam::tmp<T>::operator=(const tmp<T>& t)
 {
+    if (&t == this)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     clear();
 
     if (t.isTmp())
diff --git a/src/OpenFOAM/memory/tmp/tmpNrcI.H b/src/OpenFOAM/memory/tmp/tmpNrcI.H
index b6a1e7a1a1..fd35c741ef 100644
--- a/src/OpenFOAM/memory/tmp/tmpNrcI.H
+++ b/src/OpenFOAM/memory/tmp/tmpNrcI.H
@@ -319,6 +319,11 @@ inline void Foam::tmpNrc<T>::cref(const T& obj) noexcept
 template<class T>
 inline void Foam::tmpNrc<T>::swap(tmpNrc<T>& other) noexcept
 {
+    if (&other == this)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     // Copy/assign for pointer types
     T* p = ptr_;
     ptr_ = other.ptr_;
@@ -403,6 +408,11 @@ inline void Foam::tmpNrc<T>::operator=(T* p)
 template<class T>
 inline void Foam::tmpNrc<T>::operator=(const tmpNrc<T>& t)
 {
+    if (&t == this)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     clear();
 
     if (t.isTmp())
diff --git a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistribute.C b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistribute.C
index 6e4eee7fcb..5551bcc0b4 100644
--- a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistribute.C
+++ b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistribute.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2015-2018 OpenCFD Ltd.
+    Copyright (C) 2015-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -516,6 +516,11 @@ Foam::label Foam::mapDistribute::whichTransform(const label index) const
 
 void Foam::mapDistribute::transfer(mapDistribute& rhs)
 {
+    if (this == &rhs)
+    {
+        // Self-assignment is a no-op
+    }
+
     mapDistributeBase::transfer(rhs);
     transformElements_.transfer(rhs.transformElements_);
     transformStart_.transfer(rhs.transformStart_);
@@ -528,11 +533,9 @@ void Foam::mapDistribute::operator=(const mapDistribute& rhs)
 {
     if (this == &rhs)
     {
-        // Avoid self-assignment
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
+
     mapDistributeBase::operator=(rhs);
     transformElements_ = rhs.transformElements_;
     transformStart_ = rhs.transformStart_;
diff --git a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBase.C b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBase.C
index d5bbcab8a7..a5af2224a4 100644
--- a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBase.C
+++ b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/mapDistributeBase.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2015-2017 OpenFOAM Foundation
-    Copyright (C) 2015-2016, OpenCFD Ltd.
+    Copyright (C) 2015-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -839,6 +839,12 @@ Foam::mapDistributeBase::mapDistributeBase(Istream& is)
 
 void Foam::mapDistributeBase::transfer(mapDistributeBase& rhs)
 {
+    if (this == &rhs)
+    {
+        // Self-assignment is a no-op
+        return;
+    }
+
     constructSize_ = rhs.constructSize_;
     subMap_.transfer(rhs.subMap_);
     constructMap_.transfer(rhs.constructMap_);
@@ -1264,11 +1270,9 @@ void Foam::mapDistributeBase::operator=(const mapDistributeBase& rhs)
 {
     if (this == &rhs)
     {
-        // Avoid self assignment
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
+
     constructSize_ = rhs.constructSize_;
     subMap_ = rhs.subMap_;
     constructMap_ = rhs.constructMap_;
diff --git a/src/OpenFOAM/primitives/strings/keyType/keyTypeI.H b/src/OpenFOAM/primitives/strings/keyType/keyTypeI.H
index 8c1d8fa680..cbf710e517 100644
--- a/src/OpenFOAM/primitives/strings/keyType/keyTypeI.H
+++ b/src/OpenFOAM/primitives/strings/keyType/keyTypeI.H
@@ -170,10 +170,9 @@ inline void Foam::keyType::clear()
 
 inline void Foam::keyType::swap(keyType& s)
 {
-    // Self-swapping is a no-op
     if (this == &s)
     {
-        return;
+        return;  // Self-swap is a no-op
     }
 
     word::swap(static_cast<word&>(s));
@@ -191,10 +190,9 @@ inline bool Foam::keyType::operator()(const std::string& text) const
 
 inline void Foam::keyType::operator=(const keyType& s)
 {
-    // Self-assignment is a no-op
     if (this == &s)
     {
-        return;
+        return;  // Self-assignment is a no-op
     }
 
     assign(s); // Bypasses char checking
@@ -204,10 +202,9 @@ inline void Foam::keyType::operator=(const keyType& s)
 
 inline void Foam::keyType::operator=(keyType&& s)
 {
-    // Self-assignment is a no-op
     if (this == &s)
     {
-        return;
+        return;  // Self-assignment is a no-op
     }
 
     clear();
diff --git a/src/OpenFOAM/primitives/strings/lists/hashedWordListI.H b/src/OpenFOAM/primitives/strings/lists/hashedWordListI.H
index bb20a17639..17ab7f3238 100644
--- a/src/OpenFOAM/primitives/strings/lists/hashedWordListI.H
+++ b/src/OpenFOAM/primitives/strings/lists/hashedWordListI.H
@@ -146,6 +146,11 @@ inline bool Foam::hashedWordList::found(const word& name) const
 
 inline void Foam::hashedWordList::swap(hashedWordList& list)
 {
+    if (this == &list)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     wordList::swap(static_cast<wordList&>(list));
     lookup_.swap(list.lookup_);
 }
diff --git a/src/OpenFOAM/primitives/strings/regex/regExpCxxI.H b/src/OpenFOAM/primitives/strings/regex/regExpCxxI.H
index 4e2b3b8149..1c68adb20f 100644
--- a/src/OpenFOAM/primitives/strings/regex/regExpCxxI.H
+++ b/src/OpenFOAM/primitives/strings/regex/regExpCxxI.H
@@ -154,8 +154,12 @@ inline bool Foam::regExpCxx::clear()
 
 inline void Foam::regExpCxx::swap(regExpCxx& rgx)
 {
-    re_.swap(rgx.re_);
-    std::swap(ok_, rgx.ok_);
+    if (this != &rgx)
+    {
+        // Self-swap is a no-op
+        re_.swap(rgx.re_);
+        std::swap(ok_, rgx.ok_);
+    }
 }
 
 
diff --git a/src/OpenFOAM/primitives/strings/string/stringI.H b/src/OpenFOAM/primitives/strings/string/stringI.H
index 19ce1f9818..a5e890749e 100644
--- a/src/OpenFOAM/primitives/strings/string/stringI.H
+++ b/src/OpenFOAM/primitives/strings/string/stringI.H
@@ -265,9 +265,9 @@ inline bool Foam::string::match(const std::string& text) const
 
 inline void Foam::string::swap(std::string& str)
 {
-    // Self-swapping is a no-op
     if (this != &str)
     {
+        // Self-swap is a no-op
         std::string::swap(str);
     }
 }
diff --git a/src/OpenFOAM/primitives/strings/wordRe/wordReI.H b/src/OpenFOAM/primitives/strings/wordRe/wordReI.H
index f008f4794f..9d09b771d0 100644
--- a/src/OpenFOAM/primitives/strings/wordRe/wordReI.H
+++ b/src/OpenFOAM/primitives/strings/wordRe/wordReI.H
@@ -259,10 +259,9 @@ inline void Foam::wordRe::set(const char* str, const compOption opt)
 
 inline void Foam::wordRe::swap(wordRe& str)
 {
-    // Self-swapping is a no-op
     if (this == &str)
     {
-        return;
+        return;  // Self-swap is a no-op
     }
 
     word::swap(static_cast<word&>(str));
@@ -280,10 +279,9 @@ inline bool Foam::wordRe::operator()(const std::string& text) const
 
 inline void Foam::wordRe::operator=(const wordRe& str)
 {
-    // Self-assignment is a no-op
     if (this == &str)
     {
-        return;
+        return;  // Self-assignment is a no-op
     }
 
     assign(str);
@@ -342,10 +340,9 @@ inline void Foam::wordRe::operator=(const char* str)
 
 inline void Foam::wordRe::operator=(wordRe&& str)
 {
-    // Self-assignment is a no-op
     if (this == &str)
     {
-        return;
+        return;  // Self-assignment is a no-op
     }
 
     clear();
diff --git a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/refinementHistory.C b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/refinementHistory.C
index 10cea017c2..11b98c08c1 100644
--- a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/refinementHistory.C
+++ b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/refinementHistory.C
@@ -147,12 +147,9 @@ void Foam::refinementHistory::splitCell8::operator=(const splitCell8& s)
 {
     // Assignment operator since autoPtr otherwise 'steals' storage.
 
-    // Check for assignment to self
     if (this == &s)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     parent_ = s.parent_;
diff --git a/src/finiteArea/faMatrices/faMatrix/faMatrix.C b/src/finiteArea/faMatrices/faMatrix/faMatrix.C
index 5a80f21dd6..eef14bd5b0 100644
--- a/src/finiteArea/faMatrices/faMatrix/faMatrix.C
+++ b/src/finiteArea/faMatrices/faMatrix/faMatrix.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2016-2017 Wikki Ltd
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -712,9 +713,7 @@ void Foam::faMatrix<Type>::operator=(const faMatrix<Type>& famv)
 {
     if (this == &famv)
     {
-        FatalErrorInFunction
-            << "attempted to assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (&psi_ != &(famv.psi_))
diff --git a/src/finiteVolume/finiteVolume/convectionSchemes/convectionScheme/convectionScheme.C b/src/finiteVolume/finiteVolume/convectionSchemes/convectionScheme/convectionScheme.C
index 4b3f41b6fe..f21e3254db 100644
--- a/src/finiteVolume/finiteVolume/convectionSchemes/convectionScheme/convectionScheme.C
+++ b/src/finiteVolume/finiteVolume/convectionSchemes/convectionScheme/convectionScheme.C
@@ -159,9 +159,7 @@ void convectionScheme<Type>::operator=(const convectionScheme<Type>& cs)
 {
     if (this == &cs)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 }
 
diff --git a/src/finiteVolume/fvMatrices/fvMatrix/fvMatrix.C b/src/finiteVolume/fvMatrices/fvMatrix/fvMatrix.C
index e08e91f6e4..1aeeb961e0 100644
--- a/src/finiteVolume/fvMatrices/fvMatrix/fvMatrix.C
+++ b/src/finiteVolume/fvMatrices/fvMatrix/fvMatrix.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2016 OpenCFD Ltd.
+    Copyright (C) 2016-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -1031,9 +1031,7 @@ void Foam::fvMatrix<Type>::operator=(const fvMatrix<Type>& fvmv)
 {
     if (this == &fvmv)
     {
-        FatalErrorInFunction
-            << "attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (&psi_ != &(fvmv.psi_))
diff --git a/src/functionObjects/field/fieldAverage/fieldAverageItem/fieldAverageItem.C b/src/functionObjects/field/fieldAverage/fieldAverageItem/fieldAverageItem.C
index 850ed93d07..6396c13547 100644
--- a/src/functionObjects/field/fieldAverage/fieldAverageItem/fieldAverageItem.C
+++ b/src/functionObjects/field/fieldAverage/fieldAverageItem/fieldAverageItem.C
@@ -228,12 +228,9 @@ void Foam::functionObjects::fieldAverageItem::operator=
     const fieldAverageItem& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self" << nl
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     // Set updated values
diff --git a/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/CollisionRecordList.C b/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/CollisionRecordList.C
index bbc7a9dcef..fecdcb9177 100644
--- a/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/CollisionRecordList.C
+++ b/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/CollisionRecordList.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -393,12 +394,9 @@ void Foam::CollisionRecordList<PairType, WallType>::operator=
     const CollisionRecordList<PairType, WallType>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     pairRecords_ = rhs.pairRecords_;
diff --git a/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/PairCollisionRecord/PairCollisionRecord.C b/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/PairCollisionRecord/PairCollisionRecord.C
index e96f8f87cb..e6d921c7f1 100644
--- a/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/PairCollisionRecord/PairCollisionRecord.C
+++ b/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/PairCollisionRecord/PairCollisionRecord.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -87,12 +88,9 @@ void Foam::PairCollisionRecord<Type>::operator=
     const PairCollisionRecord<Type>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     origProcOfOther_ = rhs.origProcOfOther_;
diff --git a/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/WallCollisionRecord/WallCollisionRecord.C b/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/WallCollisionRecord/WallCollisionRecord.C
index a6073dfb8f..581828a593 100644
--- a/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/WallCollisionRecord/WallCollisionRecord.C
+++ b/src/lagrangian/intermediate/parcels/Templates/CollidingParcel/CollisionRecordList/WallCollisionRecord/WallCollisionRecord.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -85,12 +86,9 @@ void Foam::WallCollisionRecord<Type>::operator=
     const WallCollisionRecord<Type>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     accessed_ = rhs.accessed_;
diff --git a/src/lagrangian/molecularDynamics/molecularMeasurements/bufferedAccumulator/bufferedAccumulator.C b/src/lagrangian/molecularDynamics/molecularMeasurements/bufferedAccumulator/bufferedAccumulator.C
index a2954a60ae..42b88a90ba 100644
--- a/src/lagrangian/molecularDynamics/molecularMeasurements/bufferedAccumulator/bufferedAccumulator.C
+++ b/src/lagrangian/molecularDynamics/molecularMeasurements/bufferedAccumulator/bufferedAccumulator.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
+    Copyright (C) 2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -211,12 +212,9 @@ void Foam::bufferedAccumulator<Type>::operator=
     const bufferedAccumulator<Type>& rhs
 )
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     List<Field<Type>>::operator=(rhs);
@@ -229,6 +227,6 @@ void Foam::bufferedAccumulator<Type>::operator=
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
-    #include "bufferedAccumulatorIO.C"
+#include "bufferedAccumulatorIO.C"
 
 // ************************************************************************* //
diff --git a/src/lagrangian/molecularDynamics/molecularMeasurements/distribution/distribution.C b/src/lagrangian/molecularDynamics/molecularMeasurements/distribution/distribution.C
index 26078ed741..1cf639b836 100644
--- a/src/lagrangian/molecularDynamics/molecularMeasurements/distribution/distribution.C
+++ b/src/lagrangian/molecularDynamics/molecularMeasurements/distribution/distribution.C
@@ -432,12 +432,9 @@ Foam::List<Foam::Pair<Foam::scalar>> Foam::distribution::raw()
 
 void Foam::distribution::operator=(const distribution& rhs)
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     Map<label>::operator=(rhs);
diff --git a/src/meshTools/triSurface/surfaceFeatures/surfaceFeatures.C b/src/meshTools/triSurface/surfaceFeatures/surfaceFeatures.C
index eca7f56c31..11053f5ad1 100644
--- a/src/meshTools/triSurface/surfaceFeatures/surfaceFeatures.C
+++ b/src/meshTools/triSurface/surfaceFeatures/surfaceFeatures.C
@@ -1805,12 +1805,9 @@ void Foam::surfaceFeatures::nearestFeatEdge
 
 void Foam::surfaceFeatures::operator=(const surfaceFeatures& rhs)
 {
-    // Check for assignment to self
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     if (&surf_ != &rhs.surface())
diff --git a/src/sampling/surface/cutting/cuttingPlane.C b/src/sampling/surface/cutting/cuttingPlane.C
index 15cdde491c..15a773ae52 100644
--- a/src/sampling/surface/cutting/cuttingPlane.C
+++ b/src/sampling/surface/cutting/cuttingPlane.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2018 OpenCFD Ltd.
+    Copyright (C) 2018-2019 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -150,9 +150,7 @@ void Foam::cuttingPlane::operator=(const cuttingPlane& rhs)
 {
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     static_cast<MeshStorage&>(*this) = rhs;
diff --git a/src/sampling/surface/cutting/cuttingSurfaceBase.C b/src/sampling/surface/cutting/cuttingSurfaceBase.C
index 8503608491..a207e3ae36 100644
--- a/src/sampling/surface/cutting/cuttingSurfaceBase.C
+++ b/src/sampling/surface/cutting/cuttingSurfaceBase.C
@@ -98,9 +98,7 @@ void Foam::cuttingSurfaceBase::operator=(const cuttingSurfaceBase& rhs)
 {
     if (this == &rhs)
     {
-        FatalErrorInFunction
-            << "Attempted assignment to self"
-            << abort(FatalError);
+        return;  // Self-assignment is a no-op
     }
 
     static_cast<MeshStorage&>(*this) = rhs;
diff --git a/src/surfMesh/MeshedSurface/MeshedSurface.C b/src/surfMesh/MeshedSurface/MeshedSurface.C
index 34750f135f..c9b491e330 100644
--- a/src/surfMesh/MeshedSurface/MeshedSurface.C
+++ b/src/surfMesh/MeshedSurface/MeshedSurface.C
@@ -1109,6 +1109,11 @@ void Foam::MeshedSurface<Face>::swap
     MeshedSurface<Face>& surf
 )
 {
+    if (this == &surf)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     ParentType::clearOut(); // Topology changes
     surf.clearOut();        // Topology changes
 
@@ -1139,6 +1144,11 @@ void Foam::MeshedSurface<Face>::transfer
     MeshedSurface<Face>& surf
 )
 {
+    if (this == &surf)
+    {
+        return;  // Self-assigment is a no-op
+    }
+
     ParentType::clearOut();  // Topology changes
 
     this->storedPoints().transfer(surf.storedPoints());
diff --git a/src/surfMesh/UnsortedMeshedSurface/UnsortedMeshedSurface.C b/src/surfMesh/UnsortedMeshedSurface/UnsortedMeshedSurface.C
index 9b857d7e30..4fc6ff9b16 100644
--- a/src/surfMesh/UnsortedMeshedSurface/UnsortedMeshedSurface.C
+++ b/src/surfMesh/UnsortedMeshedSurface/UnsortedMeshedSurface.C
@@ -603,6 +603,11 @@ void Foam::UnsortedMeshedSurface<Face>::swap
     UnsortedMeshedSurface<Face>& surf
 )
 {
+    if (this == &surf)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     this->clearOut();  // Topology changes
     surf.clearOut();   // Topology changes
 
@@ -622,6 +627,11 @@ void Foam::UnsortedMeshedSurface<Face>::transfer
     UnsortedMeshedSurface<Face>& surf
 )
 {
+    if (this == &surf)
+    {
+        return;  // Self-assignment is a no-op
+    }
+
     this->clear();
 
     this->storedPoints().transfer(surf.storedPoints());
diff --git a/src/surfMesh/triSurface/triSurface.C b/src/surfMesh/triSurface/triSurface.C
index 36bb8fcdc1..69cf3036f7 100644
--- a/src/surfMesh/triSurface/triSurface.C
+++ b/src/surfMesh/triSurface/triSurface.C
@@ -549,6 +549,11 @@ void Foam::triSurface::clearOut()
 
 void Foam::triSurface::swap(triSurface& surf)
 {
+    if (this == &surf)
+    {
+        return;  // Self-swap is a no-op
+    }
+
     clearOut();
     surf.clearOut();