Remove `noexcept` qualifier copy-ctor of `union` type (#5800) (#5802)

- Remove `noexcept` qualifier from generated 'union' copy-constructor
- Remove `noexcept` qualifier from generated 'union' assign-operator

5 files changed, 27 insertions, 30 deletions

diff --git a/samples/monster_generated.h b/samples/monster_generated.h
index 6c5267c9..4e49d5f9 100644
--- a/samples/monster_generated.h
+++ b/samples/monster_generated.h
@@ -111,8 +111,8 @@ struct EquipmentUnion {
   EquipmentUnion(EquipmentUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(Equipment_NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  EquipmentUnion(const EquipmentUnion &) FLATBUFFERS_NOEXCEPT;
-  EquipmentUnion &operator=(const EquipmentUnion &u) FLATBUFFERS_NOEXCEPT
+  EquipmentUnion(const EquipmentUnion &);
+  EquipmentUnion &operator=(const EquipmentUnion &u)
     { EquipmentUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   EquipmentUnion &operator=(EquipmentUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -694,7 +694,7 @@ inline flatbuffers::Offset<void> EquipmentUnion::Pack(flatbuffers::FlatBufferBui
   }
 }
 
-inline EquipmentUnion::EquipmentUnion(const EquipmentUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline EquipmentUnion::EquipmentUnion(const EquipmentUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case Equipment_Weapon: {
       value = new MyGame::Sample::WeaponT(*reinterpret_cast<MyGame::Sample::WeaponT *>(u.value));
diff --git a/src/idl_gen_cpp.cpp b/src/idl_gen_cpp.cpp
index 9903ae49..f78ee268 100644
--- a/src/idl_gen_cpp.cpp
+++ b/src/idl_gen_cpp.cpp
@@ -1227,10 +1227,8 @@ class CppGenerator : public BaseGenerator {
       code_ += "  {{NAME}}Union({{NAME}}Union&& u) FLATBUFFERS_NOEXCEPT :";
       code_ += "    type({{NONE}}), value(nullptr)";
       code_ += "    { std::swap(type, u.type); std::swap(value, u.value); }";
-      code_ += "  {{NAME}}Union(const {{NAME}}Union &) FLATBUFFERS_NOEXCEPT;";
-      code_ +=
-          "  {{NAME}}Union &operator=(const {{NAME}}Union &u) "
-          "FLATBUFFERS_NOEXCEPT";
+      code_ += "  {{NAME}}Union(const {{NAME}}Union &);";
+      code_ += "  {{NAME}}Union &operator=(const {{NAME}}Union &u)";
       code_ +=
           "    { {{NAME}}Union t(u); std::swap(type, t.type); std::swap(value, "
           "t.value); return *this; }";
@@ -1469,8 +1467,7 @@ class CppGenerator : public BaseGenerator {
       // Union copy constructor
       code_ +=
           "inline {{ENUM_NAME}}Union::{{ENUM_NAME}}Union(const "
-          "{{ENUM_NAME}}Union &u) FLATBUFFERS_NOEXCEPT : type(u.type), "
-          "value(nullptr) {";
+          "{{ENUM_NAME}}Union &u) : type(u.type), value(nullptr) {";
       code_ += "  switch (type) {";
       for (auto it = enum_def.Vals().begin(); it != enum_def.Vals().end();
            ++it) {
diff --git a/tests/cpp17/generated_cpp17/monster_test_generated.h b/tests/cpp17/generated_cpp17/monster_test_generated.h
index d32d84a4..928d8dd0 100644
--- a/tests/cpp17/generated_cpp17/monster_test_generated.h
+++ b/tests/cpp17/generated_cpp17/monster_test_generated.h
@@ -216,8 +216,8 @@ struct AnyUnion {
   AnyUnion(AnyUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(Any::NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  AnyUnion(const AnyUnion &) FLATBUFFERS_NOEXCEPT;
-  AnyUnion &operator=(const AnyUnion &u) FLATBUFFERS_NOEXCEPT
+  AnyUnion(const AnyUnion &);
+  AnyUnion &operator=(const AnyUnion &u)
     { AnyUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   AnyUnion &operator=(AnyUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -329,8 +329,8 @@ struct AnyUniqueAliasesUnion {
   AnyUniqueAliasesUnion(AnyUniqueAliasesUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(AnyUniqueAliases::NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &) FLATBUFFERS_NOEXCEPT;
-  AnyUniqueAliasesUnion &operator=(const AnyUniqueAliasesUnion &u) FLATBUFFERS_NOEXCEPT
+  AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &);
+  AnyUniqueAliasesUnion &operator=(const AnyUniqueAliasesUnion &u)
     { AnyUniqueAliasesUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   AnyUniqueAliasesUnion &operator=(AnyUniqueAliasesUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -426,8 +426,8 @@ struct AnyAmbiguousAliasesUnion {
   AnyAmbiguousAliasesUnion(AnyAmbiguousAliasesUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(AnyAmbiguousAliases::NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &) FLATBUFFERS_NOEXCEPT;
-  AnyAmbiguousAliasesUnion &operator=(const AnyAmbiguousAliasesUnion &u) FLATBUFFERS_NOEXCEPT
+  AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &);
+  AnyAmbiguousAliasesUnion &operator=(const AnyAmbiguousAliasesUnion &u)
     { AnyAmbiguousAliasesUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   AnyAmbiguousAliasesUnion &operator=(AnyAmbiguousAliasesUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -2630,7 +2630,7 @@ inline flatbuffers::Offset<void> AnyUnion::Pack(flatbuffers::FlatBufferBuilder &
   }
 }
 
-inline AnyUnion::AnyUnion(const AnyUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline AnyUnion::AnyUnion(const AnyUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case Any::Monster: {
       FLATBUFFERS_ASSERT(false);  // MyGame::Example::MonsterT not copyable.
@@ -2741,7 +2741,7 @@ inline flatbuffers::Offset<void> AnyUniqueAliasesUnion::Pack(flatbuffers::FlatBu
   }
 }
 
-inline AnyUniqueAliasesUnion::AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline AnyUniqueAliasesUnion::AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case AnyUniqueAliases::M: {
       FLATBUFFERS_ASSERT(false);  // MyGame::Example::MonsterT not copyable.
@@ -2852,7 +2852,7 @@ inline flatbuffers::Offset<void> AnyAmbiguousAliasesUnion::Pack(flatbuffers::Fla
   }
 }
 
-inline AnyAmbiguousAliasesUnion::AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline AnyAmbiguousAliasesUnion::AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case AnyAmbiguousAliases::M1: {
       FLATBUFFERS_ASSERT(false);  // MyGame::Example::MonsterT not copyable.
diff --git a/tests/monster_test_generated.h b/tests/monster_test_generated.h
index 2808dc70..b0512a26 100644
--- a/tests/monster_test_generated.h
+++ b/tests/monster_test_generated.h
@@ -244,8 +244,8 @@ struct AnyUnion {
   AnyUnion(AnyUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(Any_NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  AnyUnion(const AnyUnion &) FLATBUFFERS_NOEXCEPT;
-  AnyUnion &operator=(const AnyUnion &u) FLATBUFFERS_NOEXCEPT
+  AnyUnion(const AnyUnion &);
+  AnyUnion &operator=(const AnyUnion &u)
     { AnyUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   AnyUnion &operator=(AnyUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -386,8 +386,8 @@ struct AnyUniqueAliasesUnion {
   AnyUniqueAliasesUnion(AnyUniqueAliasesUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(AnyUniqueAliases_NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &) FLATBUFFERS_NOEXCEPT;
-  AnyUniqueAliasesUnion &operator=(const AnyUniqueAliasesUnion &u) FLATBUFFERS_NOEXCEPT
+  AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &);
+  AnyUniqueAliasesUnion &operator=(const AnyUniqueAliasesUnion &u)
     { AnyUniqueAliasesUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   AnyUniqueAliasesUnion &operator=(AnyUniqueAliasesUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -512,8 +512,8 @@ struct AnyAmbiguousAliasesUnion {
   AnyAmbiguousAliasesUnion(AnyAmbiguousAliasesUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(AnyAmbiguousAliases_NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &) FLATBUFFERS_NOEXCEPT;
-  AnyAmbiguousAliasesUnion &operator=(const AnyAmbiguousAliasesUnion &u) FLATBUFFERS_NOEXCEPT
+  AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &);
+  AnyAmbiguousAliasesUnion &operator=(const AnyAmbiguousAliasesUnion &u)
     { AnyAmbiguousAliasesUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   AnyAmbiguousAliasesUnion &operator=(AnyAmbiguousAliasesUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -2865,7 +2865,7 @@ inline flatbuffers::Offset<void> AnyUnion::Pack(flatbuffers::FlatBufferBuilder &
   }
 }
 
-inline AnyUnion::AnyUnion(const AnyUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline AnyUnion::AnyUnion(const AnyUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case Any_Monster: {
       FLATBUFFERS_ASSERT(false);  // MyGame::Example::MonsterT not copyable.
@@ -2976,7 +2976,7 @@ inline flatbuffers::Offset<void> AnyUniqueAliasesUnion::Pack(flatbuffers::FlatBu
   }
 }
 
-inline AnyUniqueAliasesUnion::AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline AnyUniqueAliasesUnion::AnyUniqueAliasesUnion(const AnyUniqueAliasesUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case AnyUniqueAliases_M: {
       FLATBUFFERS_ASSERT(false);  // MyGame::Example::MonsterT not copyable.
@@ -3087,7 +3087,7 @@ inline flatbuffers::Offset<void> AnyAmbiguousAliasesUnion::Pack(flatbuffers::Fla
   }
 }
 
-inline AnyAmbiguousAliasesUnion::AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline AnyAmbiguousAliasesUnion::AnyAmbiguousAliasesUnion(const AnyAmbiguousAliasesUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case AnyAmbiguousAliases_M1: {
       FLATBUFFERS_ASSERT(false);  // MyGame::Example::MonsterT not copyable.
diff --git a/tests/union_vector/union_vector_generated.h b/tests/union_vector/union_vector_generated.h
index d65c77cd..a03f7227 100644
--- a/tests/union_vector/union_vector_generated.h
+++ b/tests/union_vector/union_vector_generated.h
@@ -88,8 +88,8 @@ struct CharacterUnion {
   CharacterUnion(CharacterUnion&& u) FLATBUFFERS_NOEXCEPT :
     type(Character_NONE), value(nullptr)
     { std::swap(type, u.type); std::swap(value, u.value); }
-  CharacterUnion(const CharacterUnion &) FLATBUFFERS_NOEXCEPT;
-  CharacterUnion &operator=(const CharacterUnion &u) FLATBUFFERS_NOEXCEPT
+  CharacterUnion(const CharacterUnion &);
+  CharacterUnion &operator=(const CharacterUnion &u)
     { CharacterUnion t(u); std::swap(type, t.type); std::swap(value, t.value); return *this; }
   CharacterUnion &operator=(CharacterUnion &&u) FLATBUFFERS_NOEXCEPT
     { std::swap(type, u.type); std::swap(value, u.value); return *this; }
@@ -642,7 +642,7 @@ inline flatbuffers::Offset<void> CharacterUnion::Pack(flatbuffers::FlatBufferBui
   }
 }
 
-inline CharacterUnion::CharacterUnion(const CharacterUnion &u) FLATBUFFERS_NOEXCEPT : type(u.type), value(nullptr) {
+inline CharacterUnion::CharacterUnion(const CharacterUnion &u) : type(u.type), value(nullptr) {
   switch (type) {
     case Character_MuLan: {
       value = new AttackerT(*reinterpret_cast<AttackerT *>(u.value));