Bug 976372 - Remove support for compilers which lack support for dynamic_cast<void*>; r=dbaron

--HG--
extra : rebase_source : 83a23e3b8fa4462eb70a1844b555c7605162a497

configure.in

@@ -3189,30 +3189,6 @@ if test "$ac_cv_cpp_ambiguity_resolving_using" = yes ; then
    AC_DEFINE(HAVE_CPP_AMBIGUITY_RESOLVING_USING)
 fi
 
-dnl See if a dynamic_cast to void* gives the most derived object.
-AC_CACHE_CHECK(for C++ dynamic_cast to void*,
-               ac_cv_cpp_dynamic_cast_void_ptr,
-               [AC_TRY_RUN([class X { int i; public: virtual ~X() { } };
-                            class Y { int j; public: virtual ~Y() { } };
-                            class Z : public X, public Y { int k; };
-
-                            int main() {
-                                 Z mdo;
-                                 X *subx = (X*)&mdo;
-                                 Y *suby = (Y*)&mdo;
-                                 return !((((void*)&mdo != (void*)subx) &&
-                                           ((void*)&mdo == dynamic_cast<void*>(subx))) ||
-                                          (((void*)&mdo != (void*)suby) &&
-                                           ((void*)&mdo == dynamic_cast<void*>(suby))));
-                            }],
-                           ac_cv_cpp_dynamic_cast_void_ptr=yes,
-                           ac_cv_cpp_dynamic_cast_void_ptr=no,
-                           ac_cv_cpp_dynamic_cast_void_ptr=no)])
-if test "$ac_cv_cpp_dynamic_cast_void_ptr" = yes ; then
-   AC_DEFINE(HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR)
-fi
-
-
 dnl note that this one is reversed - if the test fails, then
 dnl we require implementations of unused virtual methods. Which
 dnl really blows because it means we'll have useless vtable
@@ -8742,7 +8718,6 @@ dnl The following defines are used by xpcom
 _NON_GLOBAL_ACDEFINES="$_NON_GLOBAL_ACDEFINES
 CPP_THROW_NEW
 HAVE_CPP_AMBIGUITY_RESOLVING_USING
-HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
 HAVE_CPP_PARTIAL_SPECIALIZATION
 HAVE_CPP_TROUBLE_COMPARING_TO_ZERO
 NEED_CPP_UNUSED_IMPLEMENTATIONS

js/src/configure.in

@@ -2588,30 +2588,6 @@ if test "$ac_cv_cpp_ambiguity_resolving_using" = yes ; then
    AC_DEFINE(HAVE_CPP_AMBIGUITY_RESOLVING_USING)
 fi
 
-dnl See if a dynamic_cast to void* gives the most derived object.
-AC_CACHE_CHECK(for C++ dynamic_cast to void*,
-               ac_cv_cpp_dynamic_cast_void_ptr,
-               [AC_TRY_RUN([class X { int i; public: virtual ~X() { } };
-                            class Y { int j; public: virtual ~Y() { } };
-                            class Z : public X, public Y { int k; };
-
-                            int main() {
-                                 Z mdo;
-                                 X *subx = (X*)&mdo;
-                                 Y *suby = (Y*)&mdo;
-                                 return !((((void*)&mdo != (void*)subx) &&
-                                           ((void*)&mdo == dynamic_cast<void*>(subx))) ||
-                                          (((void*)&mdo != (void*)suby) &&
-                                           ((void*)&mdo == dynamic_cast<void*>(suby))));
-                            }],
-                           ac_cv_cpp_dynamic_cast_void_ptr=yes,
-                           ac_cv_cpp_dynamic_cast_void_ptr=no,
-                           ac_cv_cpp_dynamic_cast_void_ptr=no)])
-if test "$ac_cv_cpp_dynamic_cast_void_ptr" = yes ; then
-   AC_DEFINE(HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR)
-fi
-
-
 dnl note that this one is reversed - if the test fails, then
 dnl we require implementations of unused virtual methods. Which
 dnl really blows because it means we'll have useless vtable

xpcom/base/nsTraceRefcntImpl.cpp

@@ -455,20 +455,12 @@ GetBloatEntry(const char* aTypeName, uint32_t aInstanceSize)
 static int DumpSerialNumbers(PLHashEntry* aHashEntry, int aIndex, void* aClosure)
 {
   serialNumberRecord* record = reinterpret_cast<serialNumberRecord *>(aHashEntry->value);
-#ifdef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
   fprintf((FILE*) aClosure, "%" PRIdPTR
                             " @%p (%d references; %d from COMPtrs)\n",
                             record->serialNumber,
                             NS_INT32_TO_PTR(aHashEntry->key),
                             record->refCount,
                             record->COMPtrCount);
-#else
-  fprintf((FILE*) aClosure, "%" PRIdPTR
-                            " @%p (%d references)\n",
-                            record->serialNumber,
-                            NS_INT32_TO_PTR(aHashEntry->key),
-                            record->refCount);
-#endif
   return HT_ENUMERATE_NEXT;
 }
 
@@ -598,7 +590,7 @@ static int32_t* GetRefCount(void* aPtr)
   }
 }
 
-#if defined(NS_IMPL_REFCNT_LOGGING) && defined(HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR)
+#if defined(NS_IMPL_REFCNT_LOGGING)
 static int32_t* GetCOMPtrCount(void* aPtr)
 {
   PLHashEntry** hep = PL_HashTableRawLookup(gSerialNumbers, PLHashNumber(NS_PTR_TO_INT32(aPtr)), aPtr);
@@ -733,7 +725,6 @@ static void InitTraceLog(void)
 
   const char* classes = getenv("XPCOM_MEM_LOG_CLASSES");
 
-#ifdef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
   if (classes) {
     (void)InitLog("XPCOM_MEM_COMPTR_LOG", "nsCOMPtr", &gCOMPtrLog);
   } else {
@@ -741,12 +732,6 @@ static void InitTraceLog(void)
       fprintf(stdout, "### XPCOM_MEM_COMPTR_LOG defined -- but XPCOM_MEM_LOG_CLASSES is not defined\n");
     }
   }
-#else
-  const char* comptr_log = getenv("XPCOM_MEM_COMPTR_LOG");
-  if (comptr_log) {
-    fprintf(stdout, "### XPCOM_MEM_COMPTR_LOG defined -- but it will not work without dynamic_cast\n");
-  }
-#endif
 
   if (classes) {
     // if XPCOM_MEM_LOG_CLASSES was set to some value, the value is interpreted
@@ -1173,7 +1158,7 @@ NS_LogDtor(void* aPtr, const char* aType, uint32_t aInstanceSize)
 EXPORT_XPCOM_API(void)
 NS_LogCOMPtrAddRef(void* aCOMPtr, nsISupports* aObject)
 {
-#if defined(NS_IMPL_REFCNT_LOGGING) && defined(HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR)
+#if defined(NS_IMPL_REFCNT_LOGGING)
   // Get the most-derived object.
   void *object = dynamic_cast<void *>(aObject);
 
@@ -1214,7 +1199,7 @@ NS_LogCOMPtrAddRef(void* aCOMPtr, nsISupports* aObject)
 EXPORT_XPCOM_API(void)
 NS_LogCOMPtrRelease(void* aCOMPtr, nsISupports* aObject)
 {
-#if defined(NS_IMPL_REFCNT_LOGGING) && defined(HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR)
+#if defined(NS_IMPL_REFCNT_LOGGING)
   // Get the most-derived object.
   void *object = dynamic_cast<void *>(aObject);
 

xpcom/xpcom-config.h.in

@@ -15,9 +15,6 @@
 /* Define if the c++ compiler can resolve ambiguity with |using| */
 #undef HAVE_CPP_AMBIGUITY_RESOLVING_USING
 
-/* Define if a dyanmic_cast to void* gives the most derived object */
-#undef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
-
 /* Define if the c++ compiler has trouble comparing a constant
  * reference to a templatized class to zero
  */