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  • Memory leaks after using typeinfo::name()

    - by icabod
    I have a program in which, partly for informational logging, I output the names of some classes as they are used (specifically I add an entry to a log saying along the lines of Messages::CSomeClass transmitted to 127.0.0.1). I do this with code similar to the following: std::string getMessageName(void) const { return std::string(typeid(*this).name()); } And yes, before anyone points it out, I realise that the output of typeinfo::name is implementation-specific. According to MSDN The type_info::name member function returns a const char* to a null-terminated string representing the human-readable name of the type. The memory pointed to is cached and should never be directly deallocated. However, when I exit my program in the debugger, any "new" use of typeinfo::name() shows up as a memory leak. If I output the information for 2 classes, I get 2 memory leaks, and so on. This hints that the cached data is never being freed. While this is not a major issue, it looks messy, and after a long debugging session it could easily hide genuine memory leaks. I have looked around and found some useful information (one SO answer gives some interesting information about how typeinfo may be implemented), but I'm wondering if this memory should normally be freed by the system, or if there is something i can do to "not notice" the leaks when debugging. I do have a back-up plan, which is to code the getMessageName method myself and not rely on typeinfo::name, but I'd like to know anyway if there's something I've missed.

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  • g++ linker error--typeinfo, but not vtable

    - by James
    I know the standard answer for a linker error about missing typeinfo usually also involves vtable and some virtual function that I forgot to actually define. I'm fairly certain that's not the situation this time. Here's the error: UI.o: In function boost::shared_ptr<Graphics::Widgets::WidgetSet>::shared_ptr<Graphics::Resource::GroupByState>(boost::shared_ptr<Graphics::Resource::GroupByState> const&, boost::detail::dynamic_cast_tag)': UI.cpp:(.text._ZN5boost10shared_ptrIN8Graphics7Widgets9WidgetSetEEC1INS1_8Resource12GroupByStateEEERKNS0_IT_EENS_6detail16dynamic_cast_tagE[boost::shared_ptr<Graphics::Widgets::WidgetSet>::shared_ptr<Graphics::Resource::GroupByState>(boost::shared_ptr<Graphics::Resource::GroupByState> const&, boost::detail::dynamic_cast_tag)]+0x30): undefined reference totypeinfo for Graphics::Widgets::WidgetSet' Running c++filt on the obnoxious mangled name shows that it actually is looking at .boost::shared_ptr::shared_ptr(boost::shared_ptr const&, boost::detail::dynamic_cast_tag) The inheritance hierarchy looks something like class AbstractGroup { typedef boost::shared_ptr<AbstractGroup> Ptr; ... }; class WidgetSet : public AbstractGroup { typedef boost::shared_ptr<WidgetSet> Ptr; ... }; class GroupByState : public AbstractGroup { ... }; Then there's this: class UI : public GroupByState { ... void LoadWidgets( GroupByState::Ptr resource ); }; Then the original implementation: void UI::LoadWidgets( GroupByState::Ptr resource ) { WidgetSet::Ptr tmp( boost::dynamic_pointer_cast< WidgetSet >(resource) ); if( tmp ) { ... } } Stupid error on my part (trying to cast to a sibling class with a shared parent), even if the error is kind of cryptic. Changing to this: void UI::LoadWidgets( AbstractGroup::Ptr resource ) { WidgetSet::Ptr tmp( boost::dynamic_pointer_cast< WidgetSet >(resource) ); if( tmp ) { ... } } (which I'm fairly sure is what I actually meant to be doing) left me with a very similar error: UI.o: In function boost::shared_ptr<Graphics::Widgets::WidgetSet>::shared_ptr<Graphics::_Drawer::Group>(boost::shared_ptr<Graphics::_Drawer::Group> const&, boost::detail::dynamic_cast_tag)': UI.cpp:(.text._ZN5boost10shared_ptrIN8Graphics7Widgets9WidgetSetEEC1INS1_7_Drawer5GroupEEERKNS0_IT_EENS_6detail16dynamic_cast_tagE[boost::shared_ptr<Graphics::Widgets::WidgetSet>::shared_ptr<Graphics::_Drawer::Group>(boost::shared_ptr<Graphics::_Drawer::Group> const&, boost::detail::dynamic_cast_tag)]+0x30): undefined reference totypeinfo for Graphics::Widgets::WidgetSet' collect2: ld returned 1 exit status dynamic_cast_tag is just an empty struct in boost/shared_ptr.hpp. It's just a guess that boost might have anything at all to do with the error. Passing in a WidgetSet::Ptr totally eliminates the need for a cast, and it builds fine (which is why I think there's more going on than the standard answer for this question). Obviously, I'm trimming away a lot of details that might be important. My next step is to cut it down to the smallest example that fails to build, but I figured I'd try the lazy way out and take a stab on here first. TIA!

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  • C++ virtual functions.Problem with vtable

    - by adivasile
    I'm doing a little project in C++ and I've come into some problems regarding virtual functions. I have a base class with some virtual functions: #ifndef COLLISIONSHAPE_H_ #define COLLISIONSHAPE_H_ namespace domino { class CollisionShape : public DominoItem { public: // CONSTRUCTOR //------------------------------------------------- // SETTERS //------------------------------------------------- // GETTERS //------------------------------------------------- virtual void GetRadius() = 0; virtual void GetPosition() = 0; virtual void GetGrowth(CollisionShape* other) = 0; virtual void GetSceneNode(); // OTHER //------------------------------------------------- virtual bool overlaps(CollisionShape* shape) = 0; }; } #endif /* COLLISIONSHAPE_H_ */ and a SphereShape class which extends CollisionShape and implements the methods above /* SphereShape.h */ #ifndef SPHERESHAPE_H_ #define SPHERESHAPE_H_ #include "CollisionShape.h" namespace domino { class SphereShape : public CollisionShape { public: // CONSTRUCTOR //------------------------------------------------- SphereShape(); SphereShape(CollisionShape* shape1, CollisionShape* shape2); // DESTRUCTOR //------------------------------------------------- ~SphereShape(); // SETTERS //------------------------------------------------- void SetPosition(); void SetRadius(); // GETTERS //------------------------------------------------- cl_float GetRadius(); cl_float3 GetPosition(); SceneNode* GetSceneNode(); cl_float GetGrowth(CollisionShape* other); // OTHER //------------------------------------------------- bool overlaps(CollisionShape* shape); }; } #endif /* SPHERESHAPE_H_ */ and the .cpp file: /*SphereShape.cpp*/ #include "SphereShape.h" #define max(a,b) (a>b?a:b) namespace domino { // CONSTRUCTOR //------------------------------------------------- SphereShape::SphereShape(CollisionShape* shape1, CollisionShape* shape2) { } // DESTRUCTOR //------------------------------------------------- SphereShape::~SphereShape() { } // SETTERS //------------------------------------------------- void SphereShape::SetPosition() { } void SphereShape::SetRadius() { } // GETTERS //------------------------------------------------- void SphereShape::GetRadius() { } void SphereShape::GetPosition() { } void SphereShape::GetSceneNode() { } void SphereShape::GetGrowth(CollisionShape* other) { } // OTHER //------------------------------------------------- bool SphereShape::overlaps(CollisionShape* shape) { return true; } } These classes, along some other get compiled into a shared library. Building libdomino.so g++ -m32 -lpthread -ldl -L/usr/X11R6/lib -lglut -lGLU -lGL -shared -lSDKUtil -lglut -lGLEW -lOpenCL -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86 -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/TempSDKUtil/lib/x86 -L"/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86" -lSDKUtil -lglut -lGLEW -lOpenCL -o build/debug/x86/libdomino.so build/debug/x86//Material.o build/debug/x86//Body.o build/debug/x86//SphereShape.o build/debug/x86//World.o build/debug/x86//Engine.o build/debug/x86//BVHNode.o When I compile the code that uses this library I get the following error: ../../../lib/x86//libdomino.so: undefined reference to `vtable for domino::CollisionShape' ../../../lib/x86//libdomino.so: undefined reference to `typeinfo for domino::CollisionShape' Command used to compile the demo that uses the library: g++ -o build/debug/x86/startdemo build/debug/x86//CMesh.o build/debug/x86//CSceneNode.o build/debug/x86//OFF.o build/debug/x86//Light.o build/debug/x86//main.o build/debug/x86//Camera.o -m32 -lpthread -ldl -L/usr/X11R6/lib -lglut -lGLU -lGL -lSDKUtil -lglut -lGLEW -ldomino -lSDKUtil -lOpenCL -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86 -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/TempSDKUtil/lib/x86 -L../../../lib/x86/ -L"/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86" (the -ldomino flag) And when I run the demo, I manually tell it about the library: LD_LIBRARY_PATH=../../lib/x86/:$AMDAPPSDKROOT/lib/x86:$LD_LIBRARY_PATH bin/x86/startdemo After reading a bit about virtual functions and virtual tables I understood that virtual tables are handled by the compiler and I shouldn't worry about it, so I'm a little bit confused on how to handle this issue. I'm using gcc version 4.6.0 20110530 (Red Hat 4.6.0-9) (GCC) Later edit: I'm really sorry, but I wrote the code by hand directly here. I have defined the return types in the code. I apologize to the 2 people that answered below. I have to mention that I am a beginner at using more complex project layouts in C++.By this I mean more complex makefiles, shared libraries, stuff like that.

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  • C++ template name pretty print

    - by aaa
    hello. I have need to print indented template names for debugging purposes. For example, instead of single-line, I would like to indent name like this: boost::phoenix::actor< boost::phoenix::composite< boost::phoenix::less_eval, boost::fusion::vector< boost::phoenix::argument<0>, boost::phoenix::argument<1>, I started writing my own but is getting to be complicated. Is there an existing solution? if there is not one, can you help me to finish up my implementation? I will post it if so. Thanks

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  • How To Get Type Info Without Using Generics?

    - by DaveDev
    Hi Guys I have an object obj that is passed into a helper method. public static MyTagGenerateTag<T>(this HtmlHelper htmlHelper, T obj /*, ... */) { Type t = typeof(T); foreach (PropertyInfo prop in t.GetProperties()) { object propValue = prop.GetValue(obj, null); string stringValue = propValue.ToString(); dictionary.Add(prop.Name, stringValue); } // implement GenerateTag } I've been told this is not a correct use of generics. Can somebody tell me if I can achieve the same result without specifying a generic type? If so, how? I would probably change the signature so it'd be like: public static MyTag GenerateTag(this HtmlHelper htmlHelper, object obj /*, ... */) { Type t = typeof(obj); // implement GenerateTag } but Type t = typeof(obj); is impossible. Any suggestions? Thanks Dave

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  • linking error in zxing while trying to use it in my project iphone

    - by Usman
    Hi, In My Project i need bar-code scanning. so i use zxing library but i m heaving some linking error and its getting me crazy. error is Undefined symbols: "zxing::BinaryBitmap::BinaryBitmap(zxing::Ref<zxing::Binarizer>)", referenced from: -[Decoder decode:] in Decoder.o "zxing::LuminanceSource::LuminanceSource()", referenced from: GrayBytesMonochromeBitmapSource::GrayBytesMonochromeBitmapSource(unsigned char const*, int, int, int)in GrayBytesMonochromeBitmapSource.o "zxing::qrcode::QRCodeReader::decode(zxing::Ref<zxing::BinaryBitmap>)", referenced from: -[Decoder decode:] in Decoder.o "zxing::LuminanceSource::~LuminanceSource()", referenced from: GrayBytesMonochromeBitmapSource::~GrayBytesMonochromeBitmapSource()in GrayBytesMonochromeBitmapSource.o GrayBytesMonochromeBitmapSource::~GrayBytesMonochromeBitmapSource()in GrayBytesMonochromeBitmapSource.o "zxing::ReaderException::~ReaderException()", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o "zxing::String::getText()", referenced from: -[Decoder decode:] in Decoder.o "typeinfo for zxing::LuminanceSource", referenced from: typeinfo for GrayBytesMonochromeBitmapSourcein GrayBytesMonochromeBitmapSource.o "vtable for zxing::IllegalArgumentException", referenced from: __ZTVN5zxing24IllegalArgumentExceptionE$non_lazy_ptr in Decoder.o "typeinfo for zxing::ReaderException", referenced from: GCC_except_table1 in Decoder.o "vtable for zxing::Exception", referenced from: __ZTVN5zxing9ExceptionE$non_lazy_ptr in Decoder.o "zxing::LuminanceSource::copyMatrix()", referenced from: vtable for GrayBytesMonochromeBitmapSourcein GrayBytesMonochromeBitmapSource.o "zxing::Result::getText()", referenced from: -[Decoder decode:] in Decoder.o "zxing::GlobalHistogramBinarizer::GlobalHistogramBinarizer(zxing::Ref<zxing::LuminanceSource>)", referenced from: -[Decoder decode:] in Decoder.o "zxing::IllegalArgumentException::~IllegalArgumentException()", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o "zxing::Result::getResultPoints()", referenced from: -[Decoder decode:] in Decoder.o "typeinfo for zxing::IllegalArgumentException", referenced from: GCC_except_table1 in Decoder.o "zxing::Exception::what() const", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o "vtable for zxing::ReaderException", referenced from: __ZTVN5zxing15ReaderExceptionE$non_lazy_ptr in Decoder.o "zxing::qrcode::QRCodeReader::QRCodeReader()", referenced from: -[Decoder decode:] in Decoder.o "zxing::qrcode::QRCodeReader::~QRCodeReader()", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o ld: symbol(s) not found collect2: ld returned 1 exit status "zxing::BinaryBitmap::BinaryBitmap(zxing::Ref<zxing::Binarizer>)", referenced from: -[Decoder decode:] in Decoder.o "zxing::LuminanceSource::LuminanceSource()", referenced from: GrayBytesMonochromeBitmapSource::GrayBytesMonochromeBitmapSource(unsigned char const*, int, int, int)in GrayBytesMonochromeBitmapSource.o "zxing::qrcode::QRCodeReader::decode(zxing::Ref<zxing::BinaryBitmap>)", referenced from: -[Decoder decode:] in Decoder.o "zxing::LuminanceSource::~LuminanceSource()", referenced from: GrayBytesMonochromeBitmapSource::~GrayBytesMonochromeBitmapSource()in GrayBytesMonochromeBitmapSource.o GrayBytesMonochromeBitmapSource::~GrayBytesMonochromeBitmapSource()in GrayBytesMonochromeBitmapSource.o "zxing::ReaderException::~ReaderException()", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o "zxing::String::getText()", referenced from: -[Decoder decode:] in Decoder.o "typeinfo for zxing::LuminanceSource", referenced from: typeinfo for GrayBytesMonochromeBitmapSourcein GrayBytesMonochromeBitmapSource.o "vtable for zxing::IllegalArgumentException", referenced from: __ZTVN5zxing24IllegalArgumentExceptionE$non_lazy_ptr in Decoder.o "typeinfo for zxing::ReaderException", referenced from: GCC_except_table1 in Decoder.o "vtable for zxing::Exception", referenced from: __ZTVN5zxing9ExceptionE$non_lazy_ptr in Decoder.o "zxing::LuminanceSource::copyMatrix()", referenced from: vtable for GrayBytesMonochromeBitmapSourcein GrayBytesMonochromeBitmapSource.o "zxing::Result::getText()", referenced from: -[Decoder decode:] in Decoder.o "zxing::GlobalHistogramBinarizer::GlobalHistogramBinarizer(zxing::Ref<zxing::LuminanceSource>)", referenced from: -[Decoder decode:] in Decoder.o "zxing::IllegalArgumentException::~IllegalArgumentException()", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o "zxing::Result::getResultPoints()", referenced from: -[Decoder decode:] in Decoder.o "typeinfo for zxing::IllegalArgumentException", referenced from: GCC_except_table1 in Decoder.o "zxing::Exception::what() const", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o "vtable for zxing::ReaderException", referenced from: __ZTVN5zxing15ReaderExceptionE$non_lazy_ptr in Decoder.o "zxing::qrcode::QRCodeReader::QRCodeReader()", referenced from: -[Decoder decode:] in Decoder.o "zxing::qrcode::QRCodeReader::~QRCodeReader()", referenced from: -[Decoder decode:] in Decoder.o -[Decoder decode:] in Decoder.o ld: symbol(s) not found collect2: ld returned 1 exit status i m trying to resolve this for last two day. i think i m missing some library or some file. can any one point me out what i m doing wrong. Usman

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  • pointers to member functions in an event dispatcher

    - by derivative
    For the past few days I've been trying to come up with a robust event handling system for the game (using a component based entity system, C++, OpenGL) I've been toying with. class EventDispatcher { typedef void (*CallbackFunction)(Event* event); typedef std::unordered_map<TypeInfo, std::list<CallbackFunction>, hash_TypeInfo > TypeCallbacksMap; EventQueue* global_queue_; TypeCallbacksMap callbacks_; ... } global_queue_ is a pointer to a wrapper EventQueue of std::queue<Event*> where Event is a pure virtual class. For every type of event I want to handle, I create a new derived class of Event, e.g. SetPositionEvent. TypeInfo is a wrapper on type_info. When I initialize my data, I bind functions to events in an unordered_map using TypeInfo(typeid(Event)) as the key that corresponds to a std::list of function pointers. When an event is dispatched, I iterate over the list calling the functions on that event. Those functions then static_cast the event pointer to the actual event type, so the event dispatcher needs to know very little. The actual functions that are being bound are functions for my component managers. For instance, SetPositionEvent would be handled by void PositionManager::HandleSetPositionEvent(Event* event) { SetPositionEvent* s_p_event = static_cast<SetPositionEvent*>(event); ... } The problem I'm running into is that to store a pointer to this function, it has to be static (or so everything leads me to believe.) In a perfect world, I want to store pointers member functions of a component manager that is defined in a script or whatever. It looks like I can store the instance of the component manager as well, but the typedef for this function is no longer simple and I can't find an example of how to do it. Is there a way to store a pointer to a member function of a class (along with a class instance, or, I guess a pointer to a class instance)? Is there an easier way to address this problem?

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  • Is there a C# equivalent of typeof for properties/methods/members?

    - by David
    A classes Type metadata can be obtained in several ways. Two of them are: var typeInfo = Type.GetType("MyClass") and var typeInfo = typeof(MyClass) The advantage of the second way is that typos will be caught by the compiler, and the IDE can understand what I'm talking about (allowing features like refactoring to work without silently breaking the code) Does there exist an equivalent way of strongly referencing members/properties/methods for metadata and reflection? Can I replace: var propertyInfo = typeof(MyClass).GetProperty("MyProperty") with something like: var propertyInfo = property(MyClass.MyProperty)

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  • GCC: Simple inheritance test fails

    - by knight666
    I'm building an open source 2D game engine called YoghurtGum. Right now I'm working on the Android port, using the NDK provided by Google. I was going mad because of the errors I was getting in my application, so I made a simple test program: class Base { public: Base() { } virtual ~Base() { } }; // class Base class Vehicle : virtual public Base { public: Vehicle() : Base() { } ~Vehicle() { } }; // class Vehicle class Car : public Vehicle { public: Car() : Base(), Vehicle() { } ~Car() { } }; // class Car int main(int a_Data, char** argv) { Car* stupid = new Car(); return 0; } Seems easy enough, right? Here's how I compile it, which is the same way I compile the rest of my code: /home/oem/android-ndk-r3/build/prebuilt/linux-x86/arm-eabi-4.4.0/bin/arm-eabi-g++ -g -std=c99 -Wall -Werror -O2 -w -shared -fshort-enums -I ../../YoghurtGum/src/GLES -I ../../YoghurtGum/src -I /home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/include -c src/Inheritance.cpp -o intermediate/Inheritance.o (Line breaks are added for clarity). This compiles fine. But then we get to the linker: /home/oem/android-ndk-r3/build/prebuilt/linux-x86/arm-eabi-4.4.0/bin/arm-eabi-gcc -lstdc++ -Wl, --entry=main, -rpath-link=/system/lib, -rpath-link=/home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib, -dynamic-linker=/system/bin/linker, -L/home/oem/android-ndk-r3/build/prebuilt/linux-x86/arm-eabi-4.4.0/lib/gcc/arm-eabi/4.4.0, -L/home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib, -rpath=../../YoghurtGum/lib/GLES -nostdlib -lm -lc -lGLESv1_CM -z /home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib/crtbegin_dynamic.o /home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib/crtend_android.o intermediate/Inheritance.o ../../YoghurtGum/bin/YoghurtGum.a -o bin/Galaxians.android As you can probably tell, there's a lot of cruft in there that isn't really needed. That's because it doesn't work. It fails with the following errors: intermediate/Inheritance.o:(.rodata._ZTI3Car[typeinfo for Car]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info' intermediate/Inheritance.o:(.rodata._ZTI7Vehicle[typeinfo for Vehicle]+0x0): undefined reference to `vtable for __cxxabiv1::__vmi_class_type_info' intermediate/Inheritance.o:(.rodata._ZTI4Base[typeinfo for Base]+0x0): undefined reference to `vtable for __cxxabiv1::__class_type_info' collect2: ld returned 1 exit status make: *** [bin/Galaxians.android] Fout 1 These are the same errors I get from my actual application. If someone could explain to me where I went wrong in my test or what option or I forgot in my linker, I would be very, extremely grateful. Thanks in advance. UPDATE: When I make my destructors non-inlined, I get new and more exciting link errors: intermediate/Inheritance.o:(.rodata+0x78): undefined reference to `vtable for __cxxabiv1::__si_class_type_info' intermediate/Inheritance.o:(.rodata+0x90): undefined reference to `vtable for __cxxabiv1::__vmi_class_type_info' intermediate/Inheritance.o:(.rodata+0xb0): undefined reference to `vtable for __cxxabiv1::__class_type_info' collect2: ld returned 1 exit status make: *** [bin/Galaxians.android] Fout 1

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  • Delphi TRttiType.GetMethods return zero TRttiMethod instances

    - by conciliator
    I've recently been able to fetch a TRttiType for an interface using TRttiContext.FindType using Robert Loves "GetType"-workaround ("registering" the interface by an explicit call to ctx.GetType, e.g. RType := ctx.GetType(TypeInfo(IMyPrettyLittleInterface));). One logical next step would be to iterate the methods of said interface. Consider program rtti_sb_1; {$APPTYPE CONSOLE} uses SysUtils, Rtti, mynamespace in 'mynamespace.pas'; var ctx: TRttiContext; RType: TRttiType; Method: TRttiMethod; begin ctx := TRttiContext.Create; RType := ctx.GetType(TypeInfo(IMyPrettyLittleInterface)); if RType <> nil then begin for Method in RType.GetMethods do WriteLn(Method.Name); end; ReadLn; end. This time, my mynamespace.pas looks like this: IMyPrettyLittleInterface = interface ['{6F89487E-5BB7-42FC-A760-38DA2329E0C5}'] procedure SomeProcedure; end; Unfortunately, RType.GetMethods returns a zero-length TArray-instance. Are there anyone able to reproduce my troubles? (Note that in my example I've explicitly fetched the TRttiType using TRttiContext.GetType, not the workaround; the introduction is included to warn readers that there might be some unresolved issues regarding rtti and interfaces.) Thanks!

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  • What Causes Boost Asio to Crash Like This?

    - by Scott Lawson
    My program appears to run just fine most of the time, but occasionally I get a segmentation fault. boost version = 1.41.0 running on RHEL 4 compiled with GCC 3.4.6 Backtrace: #0 0x08138546 in boost::asio::detail::posix_fd_set_adapter::is_set (this=0xb74ed020, descriptor=-1) at /home/scottl/boost_1_41_0/boost/asio/detail/posix_fd_set_adapter.hpp:57 __result = -1 'ÿ' #1 0x0813e1b0 in boost::asio::detail::reactor_op_queue::perform_operations_for_descriptors (this=0x97f3b6c, descriptors=@0xb74ed020, result=@0xb74ecec8) at /home/scottl/boost_1_41_0/boost/asio/detail/reactor_op_queue.hpp:204 op_iter = {_M_node = 0xb4169aa0} i = {_M_node = 0x97f3b74} #2 0x081382ca in boost::asio::detail::select_reactor::run (this=0x97f3b08, block=true) at /home/scottl/boost_1_41_0/boost/asio/detail/select_reactor.hpp:388 read_fds = {fd_set_ = {fds_bits = {16, 0 }}, max_descriptor_ = 65} write_fds = {fd_set_ = {fds_bits = {0 }}, max_descriptor_ = -1} retval = 1 lock = { = {}, mutex_ = @0x97f3b1c, locked_ = true} except_fds = {fd_set_ = {fds_bits = {0 }}, max_descriptor_ = -1} max_fd = 65 tv_buf = {tv_sec = 0, tv_usec = 710000} tv = (timeval *) 0xb74ecf88 ec = {m_val = 0, m_cat = 0x81f2c24} sb = { = {}, blocked_ = true, old_mask_ = {__val = {0, 0, 134590223, 3075395548, 3075395548, 3075395464, 134729792, 3075395360, 135890240, 3075395368, 134593920, 3075395544, 135890240, 3075395384, 134599542, 3020998404, 135890240, 3075395400, 134614095, 3075395544, 4, 3075395416, 134548135, 3021172996, 4294967295, 3075395432, 134692921, 3075395504, 0, 3075395448, 134548107, 3021172992}}} #3 0x0812eb45 in boost::asio::detail::task_io_service ::do_one (this=0x97f3a70, lock=@0xb74ed230, this_idle_thread=0xb74ed240, ec=@0xb74ed2c0) at /home/scottl/boost_1_41_0/boost/asio/detail/task_io_service.hpp:260 more_handlers = false c = {lock_ = @0xb74ed230, task_io_service_ = @0x97f3a70} h = (boost::asio::detail::handler_queue::handler *) 0x97f3aa0 polling = false task_has_run = true #4 0x0812765f in boost::asio::detail::task_io_service ::run (this=0x97f3a70, ec=@0xb74ed2c0) at /home/scottl/boost_1_41_0/boost/asio/detail/task_io_service.hpp:103 ctx = { = {}, owner_ = 0x97f3a70, next_ = 0x0} this_idle_thread = {wakeup_event = { = {}, cond_ = {__c_lock = { __status = 0, __spinlock = 22446}, __c_waiting = 0x2bd7, __padding = "\000\000\000\000×+\000\000\000\000\000\000×+\000\000\000\000\000\000\204:\177\t\000\000\000", __align = 0}, signalled_ = true}, next = 0x0} lock = { = {}, mutex_ = @0x97f3a84, locked_ = false} n = 11420 #5 0x08125e99 in boost::asio::io_service::run (this=0x97ebbcc) at /home/scottl/boost_1_41_0/boost/asio/impl/io_service.ipp:58 ec = {m_val = 0, m_cat = 0x81f2c24} s = 8 #6 0x08154424 in boost::_mfi::mf0::operator() (this=0x9800870, p=0x97ebbcc) at /home/scottl/boost_1_41_0/boost/bind/mem_fn_template.hpp:49 No locals. #7 0x08154331 in boost::_bi::list1 ::operator(), boost::_bi::list0 (this=0x9800878, f=@0x9800870, a=@0xb74ed337) at /home/scottl/boost_1_41_0/boost/bind/bind.hpp:236 No locals. #8 0x081541e5 in boost::_bi::bind_t, boost::_bi::list1 ::operator() (this=0x9800870) at /home/scottl/boost_1_41_0/boost/bind/bind_template.hpp:20 a = {} #9 0x08154075 in boost::detail::thread_data, boost::_bi::list1 ::run (this=0x98007a0) at /home/scottl/boost_1_41_0/boost/thread/detail/thread.hpp:56 No locals. #10 0x0816fefd in thread_proxy () at /usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/locale_facets.tcc:2443 __ioinit = {static _S_refcount = , static _S_synced_with_stdio = } ---Type to continue, or q to quit--- typeinfo for common::RuntimeException = {} typeinfo name for common::RuntimeException = "N6common16RuntimeExceptionE" #11 0x00af23cc in start_thread () from /lib/tls/libpthread.so.0 No symbol table info available. #12 0x00a5c96e in __init_misc () from /lib/tls/libc.so.6 No symbol table info available.

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  • Delphi interface cast using TValue

    - by conciliator
    I've recently experimented extensively with interfaces and D2010 RTTI. I don't know at runtime the actual type of the interface; although I will have access to it's qualified name using a string. Consider the following: program rtti_sb_1; {$APPTYPE CONSOLE} uses SysUtils, Rtti, TypInfo, mynamespace in 'mynamespace.pas'; var ctx: TRttiContext; InterfaceType: TRttiType; Method: TRttiMethod; ActualParentInstance: IParent; ChildInterfaceValue: TValue; ParentInterfaceValue: TValue; begin ctx := TRttiContext.Create; // Instantiation ActualParentInstance := TChild.Create as IParent; {$define WORKAROUND} {$ifdef WORKAROUND} InterfaceType := ctx.GetType(TypeInfo(IParent)); InterfaceType := ctx.GetType(TypeInfo(IChild)); {$endif} // Fetch interface type InterfaceType := ctx.FindType('mynamespace.IParent'); // This cast is OK and ChildMethod is executed (ActualParentInstance as IChild).ChildMethod(100); // Create a TValue holding the interface TValue.Make(@ActualParentInstance, InterfaceType.Handle, ParentInterfaceValue); InterfaceType := ctx.FindType('mynamespace.IChild'); // This cast doesn't work if ParentInterfaceValue.TryCast(InterfaceType.Handle, ChildInterfaceValue) then begin Method := InterfaceType.GetMethod('ChildMethod'); if (Method <> nil) then begin Method.Invoke(ChildInterfaceValue, [100]); end; end; ReadLn; end. The contents of mynamespace.pas is as follows: {$M+} IParent = interface ['{2375F59E-D432-4D7D-8D62-768F4225FFD1}'] procedure ParentMethod(const Id: integer); end; {$M-} IChild = interface(IParent) ['{6F89487E-5BB7-42FC-A760-38DA2329E0C5}'] procedure ChildMethod(const Id: integer); end; TParent = class(TInterfacedObject, IParent) public procedure ParentMethod(const Id: integer); end; TChild = class(TParent, IChild) public procedure ChildMethod(const Id: integer); end; For completeness, the implementation goes as procedure TParent.ParentMethod(const Id: integer); begin WriteLn('ParentMethod executed. Id is ' + IntToStr(Id)); end; procedure TChild.ChildMethod(const Id: integer); begin WriteLn('ChildMethod executed. Id is ' + IntToStr(Id)); end; The reason for {$define WORKAROUND} may be found in this post. Question: is there any way for me to make the desired type cast using RTTI? In other words: is there a way for me to invoke IChild.ChildMethod from knowing 1) the qualified name of IChild as a string, and 2) a reference to the TChild instance as a IParent interface? (After all, the hard-coded cast works fine. Is this even possible?) Thanks!

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  • Reflecting actionscript objects

    - by Chin
    Is it possible to reflect an object in actionscript and get the property names back in the order they are positioned in the class? I have tried the following var reflectionObject : Object = ObjectUtil.getClassInfo(obj); var propsArray : Array = reflectionObject.properties; (orders alphabetically) var typeInfo:XML = describeType(obj) (Not sure what order this is)

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  • Unresolved symbol when inheriting interface

    - by LeopardSkinPillBoxHat
    It's late at night here and I'm going crazy trying to solve a linker error. If I have the following abstract interface: class IArpPacketBuilder { public: IArpPacketBuilder(const DslPortId& aPortId); virtual ~IArpPacketBuilder(); // Other abstract (pure virtual methods) here... }; and I instantiate it like this: class DummyArpPacketBuilder : public IArpPacketBuilder { public: DummyArpPacketBuilder(const DslPortId& aPortId) : IArpPacketBuilder(aPortId) {} ~DummyArpPacketBuilder() {} }; why am I getting the following error when linking? Unresolved symbol references: IArpPacketBuilder::IArpPacketBuilder(DslPortId const&): ppc603_vxworks/_arpPacketQueue.o IArpPacketBuilder::~IArpPacketBuilder(): ppc603_vxworks/_arpPacketQueue.o typeinfo for IArpPacketBuilder: ppc603_vxworks/_arpPacketQueue.o *** Error code 1 IArpPacketBuilder is an abstract interface, so as long as I define the constructors and destructions in the concrete (derived) interface, I should be fine, no? Well it appears not.

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  • Compilation Error on Recursive Variadic Template Function

    - by Maxpm
    I've prepared a simple variadic template test in Code::Blocks, but I'm getting an error: No matching function for call to 'OutputSizes()' Here's my source code: #include <iostream> #include <typeinfo> using namespace std; template <typename FirstDatatype, typename... DatatypeList> void OutputSizes() { std::cout << typeid(FirstDatatype).name() << ": " << sizeof(FirstDatatype) << std::endl; OutputSizes<DatatypeList...>(); } int main() { OutputSizes<char, int, long int>(); return 0; } I'm using GNU GCC with -std=C++0x. Using std=gnu++0x makes no difference.

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  • Poco C++ library on OSX 10.8.2: Undefined symbols for architecture x86_64

    - by Arman
    I'm trying to use Poco C++ library to do the simple http requests in C++ on Mac OS X 10.8.2. I installed Poco, copy-pasted the http_request.cc code from this tutorial, ran it with 'g++ -o http_get http_get.cc -lPocoNet', but got: Undefined symbols for architecture x86_64: "Poco::StreamCopier::copyStream(std::basic_istream<char, std::char_traits<char> >&, std::basic_ostream<char, std::char_traits<char> >&, unsigned long)", referenced from: _main in ccKuZb1g.o "Poco::URI::URI(char const*)", referenced from: _main in ccKuZb1g.o "Poco::URI::~URI()", referenced from: _main in ccKuZb1g.o "Poco::URI::getPathAndQuery() const", referenced from: _main in ccKuZb1g.o "Poco::URI::getPort() const", referenced from: _main in ccKuZb1g.o "Poco::Exception::displayText() const", referenced from: _main in ccKuZb1g.o "typeinfo for Poco::Exception", referenced from: GCC_except_table1 in ccKuZb1g.o ld: symbol(s) not found for architecture x86_64 collect2: ld returned 1 exit status Have been struggling with this for couple of hours. Any idea how to fix this? Thanks in advance!

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  • Can typeid() be used to pass a function?

    - by Kerb_z
    I tried this and got the output as: void Please explain the following Code: #include <cstdio> #include <typeinfo> using namespace std ; void foo() { } int main(void) { printf("%s", typeid(foo()).name());// Please notice this line, is it same as typeid( ).name() ? return 0; } AFAIK: The typeid operator allows the type of an object to be determined at run time. So, does this sample code tell us that a function that returns void is of *type void*. I mean a function is a method and has no type. Correct?

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  • What is the general feeling about reflection extensions in std::type_info?

    - by Evan Teran
    I've noticed that reflection is one feature that developers from other languages find very lacking in c++. For certain applications I can really see why! It is so much easier to write things like an IDE's auto-complete if you had reflection. And certainly serialization APIs would be a world easier if we had it. On the other side, one of the main tenets of c++ is don't pay for what you don't use. Which makes complete sense. That's something I love about c++. But it occurred to me there could be a compromise. Why don't compilers add extensions to the std::type_info structure? There would be no runtime overhead. The binary could end up being larger, but this could be a simple compiler switch to enable/disable and to be honest, if you are really concerned about the space savings, you'll likely disable exceptions and RTTI anyway. Some people cite issues with templates, but the compiler happily generates std::type_info structures for template types already. I can imagine a g++ switch like -fenable-typeinfo-reflection which could become very popular (and mainstream libs like boost/Qt/etc could easily have a check to generate code which uses it if there, in which case the end user would benefit with no more cost than flipping a switch). I don't find this unreasonable since large portable libraries like this already depend on compiler extensions. So why isn't this more common? I imagine that I'm missing something, what are the technical issues with this?

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  • Linker error: wants C++ virtual base class destructor

    - by jdmuys
    Hi, I have a link error where the linker complains that my concrete class's destructor is calling its abstract superclass destructor, the code of which is missing. This is using GCC 4.2 on Mac OS X from XCode. I saw http://stackoverflow.com/questions/307352/g-undefined-reference-to-typeinfo but it's not quite the same thing. Here is the linker error message: Undefined symbols: "ConnectionPool::~ConnectionPool()", referenced from: AlwaysConnectedConnectionZPool::~AlwaysConnectedConnectionZPool()in RKConnector.o ld: symbol(s) not found collect2: ld returned 1 exit status Here is the abstract base class declaration: class ConnectionPool { public: static ConnectionPool* newPool(std::string h, short p, std::string u, std::string pw, std::string b); virtual ~ConnectionPool() =0; virtual int keepAlive() =0; virtual int disconnect() =0; virtual sql::Connection * getConnection(char *compression_scheme = NULL) =0; virtual void releaseConnection(sql::Connection * theConnection) =0; }; Here is the concrete class declaration: class AlwaysConnectedConnectionZPool: public ConnectionPool { protected: <snip data members> public: AlwaysConnectedConnectionZPool(std::string h, short p, std::string u, std::string pw, std::string b); virtual ~AlwaysConnectedConnectionZPool(); virtual int keepAlive(); // will make sure the connection doesn't time out. Call regularly virtual int disconnect(); // disconnects/destroys all connections. virtual sql::Connection * getConnection(char *compression_scheme = NULL); virtual void releaseConnection(sql::Connection * theConnection); }; Needless to say, all those members are implemented. Here is the destructor: AlwaysConnectedConnectionZPool::~AlwaysConnectedConnectionZPool() { printf("AlwaysConnectedConnectionZPool destructor call"); // nothing to destruct in fact } and also maybe the factory routine: ConnectionPool* ConnectionPool::newPool(std::string h, short p, std::string u, std::string pw, std::string b) { return new AlwaysConnectedConnectionZPool(h, p, u, pw, b); } I can fix this by artificially making my abstract base class concrete. But I'd rather do something better. Any idea? Thanks

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  • Type casting in C++ by detecting the current 'this' object type

    - by Elroy
    My question is related to RTTI in C++ where I'm trying to check if an object belongs to the type hierarchy of another object. The BelongsTo() method checks this. I tried using typeid, but it throws an error and I'm not sure about any other way how I can find the target type to convert to at runtime. #include <iostream> #include <typeinfo> class X { public: // Checks if the input type belongs to the type heirarchy of input object type bool BelongsTo(X* p_a) { // I'm trying to check if the current (this) type belongs to the same type // hierarchy as the input type return dynamic_cast<typeid(*p_a)*>(this) != NULL; // error C2059: syntax error 'typeid' } }; class A : public X { }; class B : public A { }; class C : public A { }; int main() { X* a = new A(); X* b = new B(); X* c = new C(); bool test1 = b->BelongsTo(a); // should return true bool test2 = b->BelongsTo(c); // should return false bool test3 = c->BelongsTo(a); // should return true } Making the method virtual and letting derived classes do it seems like a bad idea as I have a lot of classes in the same type hierarchy. Or does anybody know of any other/better way to the do the same thing? Please suggest.

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  • Calling Base Class Functions with Inherited Type

    - by Kein Mitleid
    I can't describe exactly what I want to say but I want to use base class functions with an inherited type. Like I want to declare "Coord3D operator + (Coord3D);" in one class, but if I use it with Vector3D operands, I want it to return Vector3D type instead of Coord3D. With this line of code below, I add two Vector3D's and get a Coord3D in return, as told to me by the typeid().name() function. How do I reorganize my classes so that I get a Vector3D on return? #include <iostream> #include <typeinfo> using namespace std; class Coord3D { public: float x, y, z; Coord3D (float = 0.0f, float = 0.0f, float = 0.0f); Coord3D operator + (Coord3D &); }; Coord3D::Coord3D (float a, float b, float c) { x = a; y = b; z = c; } Coord3D Coord3D::operator+ (Coord3D &param) { Coord3D temp; temp.x = x + param.x; temp.y = y + param.y; temp.z = z + param.z; return temp; } class Vector3D: public Coord3D { public: Vector3D (float a = 0.0f, float b = 0.0f, float c = 0.0f) : Coord3D (a, b, c) {}; }; int main () { Vector3D a (3, 4, 5); Vector3D b (6, 7, 8); cout << typeid(a + b).name(); return 0; }

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  • I am trying to access the individual bytes in a floating point number and I am getting unexpected results

    - by oweinh
    So I have this so far: #include <iostream> #include <string> #include <typeinfo> using namespace std; int main () { float f = 3.45; // just an example fp# char* ptr = (char*)&f; // a character pointer to the first byte of the fp#? cout << int(ptr[0]) << endl; // these lines are just to see if I get what I cout << int(ptr[1]) << endl; // am looking for... I want ints that I can cout << int(ptr[2]) << endl; // otherwise manipulate. cout << int(ptr[3]) << endl; } the result is: -51 -52 92 64 so obviously -51 and -52 are not in the byte range that I would expect for a char... I have taken information from similar questions to arrive at this code and from all discussions, a conversion from char to int is straightforward. So why negative values? I am trying to look at a four-byte number, therefore I would expect 4 integers, each in the range 0-255. I am using Codeblocks 13.12 with gcc 4.8.1 with option -std=C++11 on a Windows 8.1 device.

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  • Using 32 bit g++ to build 64bit binaries on AIX

    - by Thumbeti
    I am trying to build a 64 bit binary from C++ code using 32bit g++ compiler. I am getting the following errors while building: ============================================================================= => /usr/local/bin/g++ -shared -maix64 -fPIC -Wl,-bM:SRE -Wl,-bnoentry -Wl,-bE:gcc_shr_lib.so.exp -o gcc_shr_lib.so gcc_shr_lib.o -L/usr/local/lib ld: 0711-319 WARNING: Exported symbol not defined: gcc_whereAmI ld: 0711-317 ERROR: Undefined symbol: typeinfo for std::bad_alloc ld: 0711-317 ERROR: Undefined symbol: __gxx_personality_v0 ld: 0711-317 ERROR: Undefined symbol: vtable for std::exception ld: 0711-317 ERROR: Undefined symbol: vtable for std::bad_alloc ld: 0711-317 ERROR: Undefined symbol: .std::ios_base::Init::Init() ld: 0711-317 ERROR: Undefined symbol: .std::ios_base::Init::~Init() ld: 0711-317 ERROR: Undefined symbol: .operator new(unsigned long) ld: 0711-317 ERROR: Undefined symbol: .operator delete(void*) ld: 0711-317 ERROR: Undefined symbol: ._Unwind_Resume ld: 0711-317 ERROR: Undefined symbol: .__cxa_get_exception_ptr ld: 0711-317 ERROR: Undefined symbol: .__cxa_begin_catch ld: 0711-317 ERROR: Undefined symbol: std::cout ld: 0711-317 ERROR: Undefined symbol: .std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*) ld: 0711-317 ERROR: Undefined symbol: std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&) ld: 0711-317 ERROR: Undefined symbol: .std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char, std::char_traits<char> >& (*)(std::basic_ostream<char, std::char_traits<char> >&)) ld: 0711-317 ERROR: Undefined symbol: .std::bad_alloc::~bad_alloc() ld: 0711-317 ERROR: Undefined symbol: .__cxa_end_catch ld: 0711-317 ERROR: Undefined symbol: .__register_frame_info_table ld: 0711-317 ERROR: Undefined symbol: .__deregister_frame_info ld: 0711-345 Use the -bloadmap or -bnoquiet option to obtain more information. collect2: ld returned 8 exit status ============================================================================= It seems I need 64bit libstdc++ available on my build system. Could you please throw some light to solve this. Q1) Is it ok to build 64 bit binaries using 32 bit g++ compiler on AIX 5.2 Q2) Where should I get 64 bit libstdc++? Will this 64 bit libstdc++ work with 32bit g++ compiler?

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  • DbgHelp.dll : Problem calling SymGetModuleInfo64 from C#

    - by Civa
    Hello everyone, I have quite strange behaviour calling SymGetModuleInfo64 from C# code.I always get ERROR_INVALID_PARAMETER (87) with Marshal.GetLastWin32Error().I have already read a lot of posts regarding problems with frequent updates of IMAGEHLP_MODULE64 struct and I just downloaded latest Debugging Tools For Windows (x86) , loaded dbghelp.dll from that location and I was quite sure it would work.Nevertheless I am getting the same error.Can anyone point me what is wrong here? IMAGEHLP_MODULE64 struct is defined in my code as follows : [StructLayout(LayoutKind.Sequential)] public struct IMAGEHELP_MODULE64 { //************************************************ public int SizeOfStruct; public long BaseOfImage; public int ImageSize; public int TimeDateStamp; public int CheckSum; public int NumSyms; public SymType SymType; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string ModuleName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)] public string ImageName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)] public string LoadedImageName; //************************************************ //new elements v2 //************************************************* [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)] public string LoadedPdbName; public int CVSig; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 780)] public string CVData; public int PdbSig; public GUID PdbSig70; public int PdbAge; public bool PdbUnmatched; public bool DbgUnmatched; public bool LineNumbers; public bool GlobalSymbols; public bool TypeInfo; //************************************************ //new elements v3 //************************************************ public bool SourceIndexed; public bool Publics; //************************************************ //new elements v4 //************************************************ public int MachineType; public int Reserved; //************************************************ } the piece of code that actually calls SymGetModuleInfo64 is like this : public void GetSymbolInfo(IntPtr hProcess,long modBase64,out bool success) { success = false; DbgHelp.IMAGEHELP_MODULE64 moduleInfo = new DbgHelp.IMAGEHELP_MODULE64(); moduleInfo.SizeOfStruct = Marshal.SizeOf(moduleInfo); try { success = DbgHelp.SymGetModuleInfo64(hProcess, modBase64, out moduleInfo); if (success) { //Do the stuff here } } catch (Exception exc) { } } Im stuck here...always with error 87.Please someone points me to the right direction. By the way modBase64 is value previously populated by : modBase64 = DbgHelp.SymLoadModule64(_handle, IntPtr.Zero, fileName, null, baseAddress, size); where _handle is process handle of process being debugged,fileName is path of current loaded module, baseAddress is address base of currently loaded module and size is of course the size of current loaded module.I call this code when I get LOAD_DLL_DEBUG_EVENT. Edit : Sorry, I forgot to mention that SymGetModuleInfo64 signature is like this : [DllImport("dbghelp.dll", SetLastError = true)] public static extern bool SymGetModuleInfo64(IntPtr hProcess, long ModuleBase64, out IMAGEHELP_MODULE64 imgHelpModule); Best regards, Civa

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  • Delphi: how to set the length of a RTTI-accessed dynamic array using DynArraySetLength?

    - by conciliator
    I'd like to set the length of a dynamic array, as suggested in this post. I have two classes TMyClass and the related TChildClass defined as TChildClass = class private FField1: string; FField2: string; end; TMyClass = class private FField1: TChildClass; FField2: Array of TChildClass; end; The array augmentation is implemented as var RContext: TRttiContext; RType: TRttiType; Val: TValue; // Contains the TMyClass instance RField: TRttiField; // A field in the TMyClass instance RElementType: TRttiType; // The kind of elements in the dyn array DynArr: TRttiDynamicArrayType; Value: TValue; // Holding an instance as referenced by an array element ArrPointer: Pointer; ArrValue: TValue; ArrLength: LongInt; i: integer; begin RContext := TRTTIContext.Create; try RType := RContext.GetType(TMyClass.ClassInfo); Val := RType.GetMethod('Create').Invoke(RType.AsInstance.MetaclassType, []); RField := RType.GetField('FField2'); if (RField.FieldType is TRttiDynamicArrayType) then begin DynArr := (RField.FieldType as TRttiDynamicArrayType); RElementType := DynArr.ElementType; // Set the new length of the array ArrValue := RField.GetValue(Val.AsObject); ArrLength := 3; // Three seems like a nice number ArrPointer := ArrValue.GetReferenceToRawData; DynArraySetLength(ArrPointer, ArrValue.TypeInfo, 1, @ArrLength); { TODO : Fix 'Index out of bounds' } WriteLn(ArrValue.IsArray, ' ', ArrValue.GetArrayLength); if RElementType.IsInstance then begin for i := 0 to ArrLength - 1 do begin Value := RElementType.GetMethod('Create').Invoke(RElementType.AsInstance.MetaclassType, []); ArrValue.SetArrayElement(i, Value); // This is just a test, so let's clean up immediatly Value.Free; end; end; end; ReadLn; Val.AsObject.Free; finally RContext.Free; end; end. Being new to D2010 RTTI, I suspected the error could depend on getting ArrValue from the class instance, but the subsequent WriteLn prints "TRUE", so I've ruled that out. Disappointingly, however, the same WriteLn reports that the size of ArrValue is 0, which is confirmed by the "Index out of bounds"-exception I get when trying to set any of the elements in the array (through ArrValue.SetArrayElement(i, Value);). Do anyone know what I'm doing wrong here? (Or perhaps there is a better way to do this?) TIA!

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