Postblit is still a form of copy constructor

dlang · Aug 5, 2019 · 17432c3 · 17432c3
1 parent 011b7c6
commit 17432c3
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Showing 2 changed files with 37 additions and 13 deletions.
diff --git a/src/dmd/traits.d b/src/dmd/traits.d
@@ -597,8 +597,7 @@ Expression semanticTraits(TraitsExp e, Scope* sc)
                 sm => sm.isTemplateDeclaration() !is null) != 0;
         });
     }
-    if (e.ident == Id.isPOD ||
-        e.ident == Id.hasElaborateCopyConstructor)
+    if (e.ident == Id.isPOD)
     {
         if (dim != 1)
             return dimError(1);
@@ -615,17 +614,31 @@ Expression semanticTraits(TraitsExp e, Scope* sc)
         Type tb = t.baseElemOf();
         if (auto sd = tb.ty == Tstruct ? (cast(TypeStruct)tb).sym : null)
         {
-            if (e.ident == Id.isPOD)
-            {
-                return sd.isPOD() ? True() : False();
-            }
-            else if (e.ident == Id.hasElaborateCopyConstructor)
-            {
-                return sd.hasCopyCtor ? True() : False();
-            }
+            return sd.isPOD() ? True() : False();
         }
         return True();
     }
+    if (e.ident == Id.hasElaborateCopyConstructor)
+    {
+        if (dim != 1)
+            return dimError(1);
+
+        auto o = (*e.args)[0];
+        auto t = isType(o);
+        if (!t)
+        {
+            e.error("type expected as second argument of __traits `%s` instead of `%s`",
+                e.ident.toChars(), o.toChars());
+            return new ErrorExp();
+        }
+
+        Type tb = t.baseElemOf();
+        if (auto sd = tb.ty == Tstruct ? (cast(TypeStruct)tb).sym : null)
+        {
+            return sd.hasCopyCtor || sd.postblit ? True() : False();
+        }
+        return False();
+    }
     if (e.ident == Id.isNested)
     {
         if (dim != 1)

diff --git a/test/compilable/traits.d b/test/compilable/traits.d
@@ -101,6 +101,8 @@ struct OuterS
     {
         this (ref S rhs) {}
     }
+
+    S s;
 }
 
 void foo(T)()
@@ -112,19 +114,28 @@ void foo(T)()
     static assert (__traits(hasElaborateCopyConstructor, S!int));
 }
 
-struct U(T) {
+struct U(T)
+{
     this (ref U rhs) {}
 }
 
-struct SPostblit {
+struct SPostblit
+{
     this(this) {}
 }
 
+struct NoCpCtor { }
+class C19902 { }
+
 static assert(__traits(hasElaborateCopyConstructor, S));
 static assert(__traits(hasElaborateCopyConstructor, OuterS.S));
+static assert(__traits(hasElaborateCopyConstructor, OuterS));
 static assert(__traits(compiles, foo!int));
 static assert(__traits(compiles, foo!S));
 static assert(__traits(hasElaborateCopyConstructor, U!int));
 static assert(__traits(hasElaborateCopyConstructor, U!S));
+static assert(__traits(hasElaborateCopyConstructor, SPostblit));
 
-static assert(!__traits(hasElaborateCopyConstructor, SPostblit));
+static assert(!__traits(hasElaborateCopyConstructor, NoCpCtor));
+static assert(!__traits(hasElaborateCopyConstructor, C19902));
+static assert(!__traits(hasElaborateCopyConstructor, int));