Add implicit noexcept for move and swap functions

Author: hsutter

regression-tests/test-results/pure2-types-ordering-via-meta-functions.cpp

@@ -71,8 +71,8 @@ class mystruct {
     public: mystruct(mystruct const& that);
 
 public: auto operator=(mystruct const& that) -> mystruct& ;
-public: mystruct(mystruct&& that);
-public: auto operator=(mystruct&& that) -> mystruct& ;
+public: mystruct(mystruct&& that) noexcept;
+public: auto operator=(mystruct&& that) noexcept -> mystruct& ;
 public: explicit mystruct();
 
 #line 19 "pure2-types-ordering-via-meta-functions.cpp2"
@@ -129,9 +129,9 @@ auto main() -> int;
 auto mystruct::operator=(mystruct const& that) -> mystruct& {
                                 val = that.val;
                                 return *this;}
-mystruct::mystruct(mystruct&& that)
+mystruct::mystruct(mystruct&& that) noexcept
                                 : val{ std::move(that).val }{}
-auto mystruct::operator=(mystruct&& that) -> mystruct& {
+auto mystruct::operator=(mystruct&& that) noexcept -> mystruct& {
                                 val = std::move(that).val;
                                 return *this;}
 mystruct::mystruct(){}

regression-tests/test-results/pure2-types-smf-and-that-1-provide-everything.cpp

@@ -21,15 +21,19 @@ class myclass {
 
 
 #line 8 "pure2-types-smf-and-that-1-provide-everything.cpp2"
-    public: myclass(myclass&& that);
+    public: myclass(myclass&& that) noexcept
+#line 8 "pure2-types-smf-and-that-1-provide-everything.cpp2"
+    ;
 
 
 #line 13 "pure2-types-smf-and-that-1-provide-everything.cpp2"
     public: auto operator=(myclass const& that) -> myclass& ;
 
 
 #line 18 "pure2-types-smf-and-that-1-provide-everything.cpp2"
-    public: auto operator=(myclass&& that) -> myclass& ;
+    public: auto operator=(myclass&& that) noexcept
+#line 18 "pure2-types-smf-and-that-1-provide-everything.cpp2"
+     -> myclass& ;
 
 
 #line 22 "pure2-types-smf-and-that-1-provide-everything.cpp2"
@@ -67,7 +71,9 @@ auto main() -> int;
         std::cout << "ctor - copy (GENERAL)";
     }
 
-    myclass::myclass(myclass&& that)
+    myclass::myclass(myclass&& that) noexcept
+#line 8 "pure2-types-smf-and-that-1-provide-everything.cpp2"
+    
         : name{ std::move(that).name + "(CM)" }
         , addr{ std::move(that).addr }
 #line 8 "pure2-types-smf-and-that-1-provide-everything.cpp2"
@@ -86,7 +92,9 @@ auto main() -> int;
 #line 16 "pure2-types-smf-and-that-1-provide-everything.cpp2"
     }
 
-    auto myclass::operator=(myclass&& that) -> myclass& {
+    auto myclass::operator=(myclass&& that) noexcept
+#line 18 "pure2-types-smf-and-that-1-provide-everything.cpp2"
+     -> myclass& {
         name = std::move(that).name;
         addr = std::move(that).addr;
 #line 19 "pure2-types-smf-and-that-1-provide-everything.cpp2"

regression-tests/test-results/pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp

@@ -21,14 +21,18 @@ class myclass {
 
 
 #line 8 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
-    public: myclass(myclass&& that);
+    public: myclass(myclass&& that) noexcept
+#line 8 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
+    ;
 
 
 #line 13 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
     public: auto operator=(myclass const& that) -> myclass& ;
 
 #line 13 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
-    public: auto operator=(myclass&& that) -> myclass& ;
+    public: auto operator=(myclass&& that) noexcept
+#line 13 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
+                -> myclass& ;
 
 
 #line 18 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
@@ -70,7 +74,9 @@ auto main() -> int;
         std::cout << "ctor - copy (GENERAL)";
     }
 
-    myclass::myclass(myclass&& that)
+    myclass::myclass(myclass&& that) noexcept
+#line 8 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
+    
         : name{ std::move(that).name + "(CM)" }
         , addr{ std::move(that).addr }
 #line 8 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
@@ -89,7 +95,9 @@ auto main() -> int;
 #line 16 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
     }
 #line 13 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
-    auto myclass::operator=(myclass&& that) -> myclass& {
+    auto myclass::operator=(myclass&& that) noexcept
+#line 13 "pure2-types-smf-and-that-2-provide-mvconstruct-and-cpassign.cpp2"
+                -> myclass&        {
         name = std::move(that).name;
         addr = std::move(that).addr + "(AC)";
 

regression-tests/test-results/pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp

@@ -24,7 +24,9 @@ class myclass {
 
 
 #line 8 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
-    public: myclass(myclass&& that);
+    public: myclass(myclass&& that) noexcept
+#line 8 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
+    ;
 
 
 #line 13 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
@@ -33,7 +35,9 @@ class myclass {
     //     std::cout << "assign - copy        ";
     // }
 
-    public: auto operator=(myclass&& that) -> myclass& ;
+    public: auto operator=(myclass&& that) noexcept
+#line 18 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
+     -> myclass& ;
 
 
 #line 22 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
@@ -80,7 +84,9 @@ auto main() -> int;
 #line 6 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
     }
 
-    myclass::myclass(myclass&& that)
+    myclass::myclass(myclass&& that) noexcept
+#line 8 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
+    
         : name{ std::move(that).name + "(CM)" }
         , addr{ std::move(that).addr }
 #line 8 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
@@ -90,7 +96,9 @@ auto main() -> int;
     }
 
 #line 18 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
-    auto myclass::operator=(myclass&& that) -> myclass& {
+    auto myclass::operator=(myclass&& that) noexcept
+#line 18 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"
+     -> myclass& {
         name = std::move(that).name;
         addr = std::move(that).addr;
 #line 19 "pure2-types-smf-and-that-3-provide-mvconstruct-and-mvassign.cpp2"

regression-tests/test-results/pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp

@@ -20,7 +20,9 @@ class myclass {
     public: myclass(myclass const& that);
 
 #line 4 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
-    public: myclass(myclass&& that);
+    public: myclass(myclass&& that) noexcept
+#line 4 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
+    ;
 
 
 #line 8 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
@@ -33,7 +35,9 @@ class myclass {
 
 
 #line 18 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
-    public: auto operator=(myclass&& that) -> myclass& ;
+    public: auto operator=(myclass&& that) noexcept
+#line 18 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
+     -> myclass& ;
 
 
 #line 22 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
@@ -71,7 +75,9 @@ auto main() -> int;
         std::cout << "ctor - copy (GENERAL)";
     }
 #line 4 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
-    myclass::myclass(myclass&& that)
+    myclass::myclass(myclass&& that) noexcept
+#line 4 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
+    
         : name{ std::move(that).name }
         , addr{ std::move(that).addr }
 #line 4 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
@@ -90,7 +96,9 @@ auto main() -> int;
 #line 16 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
     }
 
-    auto myclass::operator=(myclass&& that) -> myclass& {
+    auto myclass::operator=(myclass&& that) noexcept
+#line 18 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"
+     -> myclass& {
         name = std::move(that).name;
         addr = std::move(that).addr;
 #line 19 "pure2-types-smf-and-that-4-provide-cpassign-and-mvassign.cpp2"

regression-tests/test-results/pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp

@@ -23,10 +23,14 @@ class myclass {
     public: auto operator=(myclass const& that) -> myclass& ;
 
 #line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
-    public: myclass(myclass&& that);
+    public: myclass(myclass&& that) noexcept
+#line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
+    ;
 
 #line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
-    public: auto operator=(myclass&& that) -> myclass& ;
+    public: auto operator=(myclass&& that) noexcept
+#line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
+     -> myclass& ;
 
 
 #line 8 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
@@ -87,15 +91,19 @@ auto main() -> int;
 #line 6 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
     }
 #line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
-    myclass::myclass(myclass&& that)
+    myclass::myclass(myclass&& that) noexcept
+#line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
+    
         : name{ std::move(that).name }
         , addr{ std::move(that).addr }
 #line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
     {
         std::cout << "ctor - copy (GENERAL)";
     }
 #line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
-    auto myclass::operator=(myclass&& that) -> myclass& {
+    auto myclass::operator=(myclass&& that) noexcept
+#line 4 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"
+     -> myclass& {
         name = std::move(that).name;
         addr = std::move(that).addr;
 #line 5 "pure2-types-smf-and-that-5-provide-nothing-but-general-case.cpp2"

regression-tests/test-results/pure2-types-that-parameters.cpp

@@ -26,10 +26,14 @@ class myclass {
 
 
 #line 11 "pure2-types-that-parameters.cpp2"
-    public: myclass(myclass&& that);
+    public: myclass(myclass&& that) noexcept
+#line 11 "pure2-types-that-parameters.cpp2"
+    ;
 
 #line 11 "pure2-types-that-parameters.cpp2"
-    public: auto operator=(myclass&& that) -> myclass& ;
+    public: auto operator=(myclass&& that) noexcept
+#line 11 "pure2-types-that-parameters.cpp2"
+     -> myclass& ;
 
 
 #line 16 "pure2-types-that-parameters.cpp2"
@@ -68,7 +72,9 @@ auto main() -> int;
 #line 9 "pure2-types-that-parameters.cpp2"
     }
 
-    myclass::myclass(myclass&& that)
+    myclass::myclass(myclass&& that) noexcept
+#line 11 "pure2-types-that-parameters.cpp2"
+    
         : name{ std::move(that).name }
         , addr{ std::move(that).addr }
 #line 11 "pure2-types-that-parameters.cpp2"
@@ -77,7 +83,9 @@ auto main() -> int;
 #line 14 "pure2-types-that-parameters.cpp2"
     }
 #line 11 "pure2-types-that-parameters.cpp2"
-    auto myclass::operator=(myclass&& that) -> myclass& {
+    auto myclass::operator=(myclass&& that) noexcept
+#line 11 "pure2-types-that-parameters.cpp2"
+     -> myclass& {
         name = std::move(that).name;
         addr = std::move(that).addr;
         return *this;

regression-tests/test-results/pure2-types-value-types-via-meta-functions.cpp

@@ -32,8 +32,8 @@ class widget {
 public: [[nodiscard]] auto operator<=>(widget const& that) const -> std::strong_ordering = default;
 public: widget(widget const& that);
 public: auto operator=(widget const& that) -> widget& ;
-public: widget(widget&& that);
-public: auto operator=(widget&& that) -> widget& ;
+public: widget(widget&& that) noexcept;
+public: auto operator=(widget&& that) noexcept -> widget& ;
 public: explicit widget();
 
 #line 5 "pure2-types-value-types-via-meta-functions.cpp2"
@@ -48,8 +48,8 @@ class w_widget {
 public: [[nodiscard]] auto operator<=>(w_widget const& that) const -> std::weak_ordering = default;
 public: w_widget(w_widget const& that);
 public: auto operator=(w_widget const& that) -> w_widget& ;
-public: w_widget(w_widget&& that);
-public: auto operator=(w_widget&& that) -> w_widget& ;
+public: w_widget(w_widget&& that) noexcept;
+public: auto operator=(w_widget&& that) noexcept -> w_widget& ;
 public: explicit w_widget();
 
 #line 10 "pure2-types-value-types-via-meta-functions.cpp2"
@@ -64,8 +64,8 @@ class p_widget {
 public: [[nodiscard]] auto operator<=>(p_widget const& that) const -> std::partial_ordering = default;
 public: p_widget(p_widget const& that);
 public: auto operator=(p_widget const& that) -> p_widget& ;
-public: p_widget(p_widget&& that);
-public: auto operator=(p_widget&& that) -> p_widget& ;
+public: p_widget(p_widget&& that) noexcept;
+public: auto operator=(p_widget&& that) noexcept -> p_widget& ;
 public: explicit p_widget();
 
 #line 15 "pure2-types-value-types-via-meta-functions.cpp2"
@@ -100,9 +100,9 @@ template<typename T> auto test() -> void;
 auto widget::operator=(widget const& that) -> widget& {
                                 val = that.val;
                                 return *this;}
-widget::widget(widget&& that)
+widget::widget(widget&& that) noexcept
                                 : val{ std::move(that).val }{}
-auto widget::operator=(widget&& that) -> widget& {
+auto widget::operator=(widget&& that) noexcept -> widget& {
                                 val = std::move(that).val;
                                 return *this;}
 widget::widget(){}
@@ -125,9 +125,9 @@ widget::widget(){}
 auto w_widget::operator=(w_widget const& that) -> w_widget& {
                                 val = that.val;
                                 return *this;}
-w_widget::w_widget(w_widget&& that)
+w_widget::w_widget(w_widget&& that) noexcept
                                 : val{ std::move(that).val }{}
-auto w_widget::operator=(w_widget&& that) -> w_widget& {
+auto w_widget::operator=(w_widget&& that) noexcept -> w_widget& {
                                 val = std::move(that).val;
                                 return *this;}
 w_widget::w_widget(){}
@@ -150,9 +150,9 @@ w_widget::w_widget(){}
 auto p_widget::operator=(p_widget const& that) -> p_widget& {
                                 val = that.val;
                                 return *this;}
-p_widget::p_widget(p_widget&& that)
+p_widget::p_widget(p_widget&& that) noexcept
                                 : val{ std::move(that).val }{}
-auto p_widget::operator=(p_widget&& that) -> p_widget& {
+auto p_widget::operator=(p_widget&& that) noexcept -> p_widget& {
                                 val = std::move(that).val;
                                 return *this;}
 p_widget::p_widget(){}

regression-tests/test-results/version

@@ -1,5 +1,5 @@
 
-cppfront compiler v0.2.1   Build 8515:0551
+cppfront compiler v0.2.1   Build 8515:1945
 Copyright(c) Herb Sutter   All rights reserved
 
 SPDX-License-Identifier: CC-BY-NC-ND-4.0

source/build.info

@@ -1 +1 @@
-"8515:0551"
+"8515:1945"

source/cppfront.cpp

@@ -4131,12 +4131,15 @@ class cppfront
             emit(*n.parameters);
         }
 
-        //  Add implicit noexcept when we implement proper EH
-        //  to handle calling Cpp1 code that throws
-        //if (!n.throws) {
-        //    printer.add_pad_in_this_line(-25);
-        //    printer.print_cpp2( " noexcept", n.position() );
-        //}
+        //  For now, adding implicit noexcept only for move and swap functions
+        if (
+            n.is_move()
+            || n.is_swap()
+            || generating_move_from == n.my_decl
+            )
+        {
+            printer.print_cpp2( " noexcept", n.position() );
+        }
 
         printer.print_cpp2( suffix1, n.position() );