Fix #4779 - C++ classes need TypeInfo

Author: rikkimax

gen/typinf.cpp

@@ -506,8 +506,19 @@ class DeclareOrDefineVisitor : public Visitor {
     auto cd = decl->tinfo->isTypeClass()->sym;
     DtoResolveClass(cd);
 
+    auto irclass = getIrAggr(cd, true);
     IrGlobal *irg = getIrGlobal(decl, true);
-    irg->value = getIrAggr(cd)->getClassInfoSymbol();
+    
+    auto ti = irclass->getClassInfoSymbol();
+    irg->value = ti;
+    
+    // check if the definition can be elided
+    if (irclass->suppressTypeInfo()) {
+        return;
+    }
+    
+    irclass->getClassInfoSymbol(true);
+    ti->setLinkage(TYPEINFO_LINKAGE_TYPE); // override
   }
 
   // Build all other TypeInfos.

ir/irclass.cpp

@@ -29,6 +29,7 @@
 #include "gen/runtime.h"
 #include "gen/tollvm.h"
 #include "gen/typinf.h"
+#include "gen/linkage.h"
 #include "ir/iraggr.h"
 #include "ir/irdsymbol.h"
 #include "ir/irfunction.h"
@@ -89,8 +90,10 @@ LLGlobalVariable *IrClass::getVtblSymbol(bool define) {
 
   if (define) {
     auto init = getVtblInit(); // might define vtbl
-    if (!vtbl->hasInitializer())
+    if (!vtbl->hasInitializer()) {
       defineGlobal(vtbl, init, aggrdecl);
+      vtbl->setLinkage(TYPEINFO_LINKAGE_TYPE); // override
+    }
   }
 
   return vtbl;
@@ -140,8 +143,10 @@ LLGlobalVariable *IrClass::getClassInfoSymbol(bool define) {
 
   if (define) {
     auto init = getClassInfoInit();
-    if (!typeInfo->hasInitializer())
+    if (!typeInfo->hasInitializer()) {
       defineGlobal(typeInfo, init, aggrdecl);
+      typeInfo->setLinkage(TYPEINFO_LINKAGE_TYPE); // override
+    }
   }
 
   return typeInfo;
@@ -381,7 +386,7 @@ LLConstant *IrClass::getClassInfoInit() {
   if (isInterface) {
     b.push_array(0, getNullPtr());
   } else {
-    b.push_array(cd->vtbl.length, getVtblSymbol());
+    b.push_array(cd->vtbl.length, getVtblSymbol(true)); // override
   }
 
   // Interface[] interfaces
@@ -391,7 +396,9 @@ LLConstant *IrClass::getClassInfoInit() {
   assert(!isInterface || !cd->baseClass);
   if (cd->baseClass) {
     DtoResolveClass(cd->baseClass);
-    b.push(getIrAggr(cd->baseClass)->getClassInfoSymbol());
+    auto ti = getIrAggr(cd->baseClass)->getClassInfoSymbol(true);
+    ti->setLinkage(TYPEINFO_LINKAGE_TYPE); // override
+    b.push(ti);
   } else {
     b.push_null(cinfoType);
   }
@@ -743,7 +750,7 @@ LLConstant *IrClass::getClassInfoInterfaces() {
     assert(itc && "null interface IrTypeClass");
 
     // classinfo
-    LLConstant *ci = irinter->getClassInfoSymbol();
+    LLConstant *ci = irinter->getClassInfoSymbol(true);
 
     // vtbl
     LLConstant *vtb;
@@ -772,6 +779,7 @@ LLConstant *IrClass::getClassInfoInterfaces() {
   LLConstant *arr = LLConstantArray::get(array_type, constants);
   auto ciarr = getInterfaceArraySymbol();
   defineGlobal(ciarr, arr, cd);
+  ciarr->setLinkage(TYPEINFO_LINKAGE_TYPE); // override
 
   // return null, only baseclass provide interfaces
   if (cd->vtblInterfaces->length == 0) {

tests/codegen/pragma_no_typeinfo.d

@@ -10,10 +10,10 @@ struct StructWithTypeInfo {}
 // force emission
 auto ti = typeid(StructWithTypeInfo);
 
-// CHECK: _D18pragma_no_typeinfo17ClassWithTypeInfo7__ClassZ = global %object.TypeInfo_Class
+// CHECK: _D18pragma_no_typeinfo17ClassWithTypeInfo7__ClassZ = linkonce_odr global %object.TypeInfo_Class
 class ClassWithTypeInfo {}
 
-// CHECK: _D18pragma_no_typeinfo21InterfaceWithTypeInfo11__InterfaceZ = global %object.TypeInfo_Class
+// CHECK: _D18pragma_no_typeinfo21InterfaceWithTypeInfo11__InterfaceZ = linkonce_odr global %object.TypeInfo_Class
 interface InterfaceWithTypeInfo {}
 
 

tests/codegen/static_typeid_gh1540.d

@@ -15,7 +15,7 @@ struct S
 {
 }
 
-// CHECK-DAG: _D{{.*}}1C7__ClassZ{{\"?}} = global %object.TypeInfo_Class
+// CHECK-DAG: _D{{.*}}1C7__ClassZ{{\"?}} = linkonce_odr global %object.TypeInfo_Class
 // CHECK-DAG: _D{{.*}}classvarC14TypeInfo_Class{{\"?}} = thread_local global ptr {{.*}}1C7__ClassZ
 auto classvar = typeid(C);
 

tests/linking/inputs/typeinfo_on_demand2.d

@@ -0,0 +1,13 @@
+module inputs.typeinfo_on_demand2;
+
+extern(C++) class MyClass : MyInterface1 {
+    void method() {}
+}
+
+extern(C++) interface MyInterface1 {
+    void method();
+}
+
+extern(C++) interface MyInterface2 {
+    void method();
+}

tests/linking/typeinfo_on_demand.d

@@ -0,0 +1,15 @@
+// Tests that TypeInfo is generated per CU to enable on demand usage
+
+// RUN: %ldc -of%t_lib%obj -betterC -c %S/inputs/typeinfo_on_demand2.d
+// RUN: %ldc -I%S %t_lib%obj -run %s
+
+import inputs.typeinfo_on_demand2;
+
+void main() {
+  MyChildClass mcc = new MyChildClass;
+  mcc.method();
+}
+
+extern(C++) class MyChildClass : MyClass, MyInterface2 {
+    override void method() {}
+}