fix Issue 519 - Invariant not called from autogenerated class/struct ctor/dtor

src/ddmd/clone.d

@@ -766,6 +766,7 @@ extern (C++) FuncDeclaration buildXtoHash(StructDeclaration sd, Scope* sc)
  * all the members.
  * Note the close similarity with AggregateDeclaration::buildDtor(),
  * and the ordering changes (runs forward instead of backwards).
+ * buildInv() should be run first.
  */
 extern (C++) FuncDeclaration buildPostBlit(StructDeclaration sd, Scope* sc)
 {
@@ -1088,13 +1089,21 @@ extern (C++) FuncDeclaration buildDtor(AggregateDeclaration ad, Scope* sc)
     switch (ad.dtors.dim)
     {
     case 0:
+        /* If running invariant, need a destructor to hang it on,
+         * but only do for root modules, as ones in the library may not
+         * have been compiled with useInvariants
+         */
+        if (global.params.useInvariants && ad.inv && sc._module.isRoot())
+            goto Ldefault;
+
         break;
 
     case 1:
         xdtor = ad.dtors[0];
         break;
 
     default:
+    Ldefault:
         e = null;
         stc = STCsafe | STCnothrow | STCpure | STCnogc;
         for (size_t i = 0; i < ad.dtors.dim; i++)

src/ddmd/dclass.d

@@ -950,6 +950,29 @@ extern (C++) class ClassDeclaration : AggregateDeclaration
             }
         }
 
+        version (none) // Controversial - see Bugzilla 519
+        {
+            /* If class has no constructor, but does have an invariant, create a default constructor merely
+             * as a place where the invariant call will be added.
+             */
+            if (!ctor && global.params.useInvariants && inv && !isCPPclass())
+            {
+                auto tf = new TypeFunction(null, null, 0, LINKd, inv.storage_class);
+                auto btf = cast(TypeFunction)inv.type;
+                tf.purity = btf.purity;
+                tf.isnothrow = btf.isnothrow;
+                tf.isnogc = btf.isnogc;
+                tf.trust = btf.trust;
+                auto ctor = new CtorDeclaration(loc, Loc(), 0, tf);
+                ctor.fbody = new CompoundStatement(Loc(), new Statements());
+                members.push(ctor);
+                ctor.addMember(sc, this, 1);
+                ctor.semantic(sc2);
+                this.ctor = ctor;
+                defaultCtor = ctor;
+            }
+        }
+
         dtor = buildDtor(this, sc2);
 
         if (auto f = hasIdentityOpAssign(this, sc2))

src/ddmd/dstruct.d

@@ -403,6 +403,7 @@ extern (C++) class StructDeclaration : AggregateDeclaration
          */
         aggNew = cast(NewDeclaration)search(Loc(), Id.classNew);
         aggDelete = cast(DeleteDeclaration)search(Loc(), Id.classDelete);
+        inv = buildInv(this, sc2);
 
         // Look for the constructor
         ctor = searchCtor();
@@ -417,8 +418,6 @@ extern (C++) class StructDeclaration : AggregateDeclaration
         xcmp = buildXopCmp(this, sc2);
         xhash = buildXtoHash(this, sc2);
 
-        inv = buildInv(this, sc2);
-
         Module.dprogress++;
         semanticRun = PASSsemanticdone;
         //printf("-StructDeclaration::semantic(this=%p, '%s')\n", this, toChars());

src/ddmd/e2ir.d

@@ -5686,6 +5686,18 @@ private elem *toElemStructLit(StructLiteralExp sle, IRState *irs, TOK op, Symbol
         e = el_combine(e, e1);
     }
 
+    if (global.params.useInvariants && sle.sd.inv)
+    {
+        /* If there are no arguments, then this is default initialization and shouldn't call invariant.
+         */
+        if (dim)
+        {
+            FuncDeclaration inv = sle.sd.inv;
+            elem *einv = callfunc(sle.loc, irs, 1, inv.type.nextOf(), el_ptr(stmp), sle.sd.type.pointerTo(), inv, inv.type, null, null);
+            e = el_combine(e, einv);
+        }
+    }
+
     elem *ev = el_var(stmp);
     ev.ET = Type_toCtype(sle.sd.type);
     e = el_combine(e, ev);

test/runnable/testdstress.d

@@ -809,10 +809,12 @@ class Parent40{
 
         invariant()
         {
-                assert(!checked40);
+            if (!checked40)
+            {
                 checked40=true;
                 // even number
                 assert((x&1u)==0);
+            }
         }
 }
 

test/runnable/testinvariant.d

@@ -177,6 +177,75 @@ void test13147()
 }
 
 
+/***************************************************/
+
+class C519 {
+        invariant {
+                ++x;
+        }
+        __gshared int x;
+}
+
+void test519a() {
+        auto s = new C519();
+        assert(C519.x == 0);
+        delete s;
+        assert(C519.x == 1);
+}
+
+/***************************************************/
+
+struct S519 {
+    invariant() {
+        printf("S519.invariant\n");
+        ++x;
+    }
+    __gshared int x;
+}
+
+void test519b() {
+  {
+    auto foo = new S519();
+    printf("lifetime of foo\n");
+    delete foo;
+    assert(S519.x == 1);
+  }
+  printf("test2\n");
+  {
+    auto foo = S519();
+    printf("lifetime of foo\n");
+  }
+  assert(S519.x == 2);
+}
+
+
+/***************************************************/
+
+struct S519c {
+    invariant() {
+        printf("S519c.invariant\n");
+        ++x;
+    }
+    __gshared int x;
+    int y;
+}
+
+void test519c() {
+  {
+    auto foo = new S519c(1);
+    printf("lifetime of foo\n");
+    delete foo;
+    assert(S519c.x == 2);
+  }
+  printf("test2\n");
+  {
+    auto foo = S519c(1);
+    printf("lifetime of foo\n");
+  }
+  assert(S519c.x == 4);
+}
+
+
 /***************************************************/
 
 void main()
@@ -185,4 +254,7 @@ void main()
     test6453();
     test13113();
     test13147();
+    test519a();
+    test519b();
+    test519c();
 }