Are there any compelling performance reasons to choose static linking over dynamic linking or vice versa in certain situations? I've heard or read the following, but I don't know enough on the subject to vouch for its veracity. 1) The difference in runtime performance between static linking and dynamic linking is usually negligible. 2) (1) is not true if using a profiling compiler th
在某些情况下，是否有任何令人信服的性能原因来选择通过动态链接进行静态链接，反之亦然？ 我听过或读过以下内容，但我对这个主题不太了解，不能保证其准确性。 1）静态链接和动态链接之间的运行时性能差异通常可以忽略不计。 2）（1）如果使用分析编译器使用概要文件数据优化程序热路径，因为使用静态链接，编译器可以优化代码和库代码。 通过动态链接，只有您的代码可以被优化。 如果大部分时间用于运行库代码，这可能
I am trying to store different objects in one global table with void* pointer. Problem is how to retrieve the void* object back. If I have one common base class, say Object , I can always store the void* pointer as Object and then cast back to Object*. From Object* I can cast further to the specific type. class Object{}; class A : public Object{ virtual ~A()} class B : public A { } class C :
我试图用void *指针在一个全局表中存储不同的对象。 问题是如何检索void *对象。 如果我有一个公共基类，比如Object，我总是可以将void *指针存储为Object，然后将其转换回Object *。 从对象*我可以进一步投射到特定类型。 class Object{}; class A : public Object{ virtual ~A()} class B : public A { } class C : public Object{ virtual ~C()} class D: public C{}; A* aObj = new B; void* v = static_cast<Object
I am working with an abstract base class implementing a set of system tests. In simplified form, the class declaration is: class Test_Class { Test_Class(); ~Test_Class(); Run_Test(void * param_set = NULL) = 0; } The base class requires the implementation of the Run_Test function which allows a user to pass in an arbitrary data structure as a void pointer and cast it to the appropr
我正在使用抽象基类实现一组系统测试。 以简化的形式，类声明是： class Test_Class { Test_Class(); ~Test_Class(); Run_Test(void * param_set = NULL) = 0; } 基类需要实现Run_Test函数，该函数允许用户将任意数据结构作为void指针传递并将其转换为子类中的Run_Test主体内的适当类型，以便允许使用不同的测试不同的数据结构，例如一次测试中的浮点数与另一次测试中的整数列表。 这很麻烦，看起来像一个非常
I have some hierarchy: base, derived classes and some structure storing user data as void*. That void can store both Base and Derived classes pointers. Main problem that I do not know what is stored there base or derived pointer. class Base { public: int type; }; class Derived: public Base {}; Base* base;//init base pointer Derived* derived;//init derived pointer void* base_v = base; void*
我有一些层次结构：基类，派生类和一些将用户数据存储为void *的结构。 该void可以存储Base和Derived类指针。 主要的问题是我不知道存储在那里的基础或派生指针。 class Base { public: int type; }; class Derived: public Base {}; Base* base;//init base pointer Derived* derived;//init derived pointer void* base_v = base; void* derived_v = derived; //void pointers are correct. They point to base and deri
I struggled finding a how-to which provides a stable solution for using Qt with Visual Studio 2010, so after collecting all the bits of information and some trial and error, I would like to write my solution into a guide. The problem, or why is it not possible to use prebuilt binaries? It seems that using binaries built for Visual Studio 2008 might work in some special cases, but I found them
我努力寻找一种方法，它为在Visual Studio 2010中使用Qt提供了一个稳定的解决方案，因此在收集了所有信息和一些试验和错误之后，我想将我的解决方案写入指南。 这个问题，或为什么不可能使用预先构建的二进制文件？ 似乎使用为Visual Studio 2008构建的二进制文件可能在某些特殊情况下工作，但我发现它们不起作用。 在我的情况下，他们编译好，但他们产生运行时错误，就像这样： 或从Visual Studio 2010启动时： 更新
The following code shows unexpected behaviour on my machine (tested with Visual C++ 2008 SP1 on Windows XP and VS 2012 on Windows 7): #include <iostream> #include "Windows.h" int main() { SetConsoleOutputCP( CP_UTF8 ); std::cout << "xc3xbc"; int fail = std::cout.fail() ? '1': '0'; fputc( fail, stdout ); fputs( "xc3xbc", stdout ); } I simply compiled with cl /EHs
以下代码显示了我的计算机上的意外行为（在Windows 7上使用Windows XP和VS 2012上的Visual C ++ 2008 SP1进行了测试）： #include <iostream> #include "Windows.h" int main() { SetConsoleOutputCP( CP_UTF8 ); std::cout << "xc3xbc"; int fail = std::cout.fail() ? '1': '0'; fputc( fail, stdout ); fputs( "xc3xbc", stdout ); } 我简单地用cl /EHsc test.cpp编译。 Windows XP：在
I'm trying to write some Doxygen comment blocks, and I'd like to include example snippets of code. Of course, I'd like the examples to actually compile so they don't get stale. My example.cpp (that I include in the .h file) looks like this: #include "stdafx.h" #include "../types_lib/Time_Limiter.h" #include <vector> void tl_demo () { // scarce will be a gate to con
我正在尝试编写一些Doxygen注释块，并且我想包含示例代码片段。 当然，我希望这些示例能够真正编译，以免它们过时。 我的example.cpp（包含在.h文件中）看起来像这样： #include "stdafx.h" #include "../types_lib/Time_Limiter.h" #include <vector> void tl_demo () { // scarce will be a gate to control some resource that shouldn't get called // more than 10 times a second Time_Limiter sca
I am asking this question with refernce to this SO question. Accepted answer by Don stewart : First line says "Your code is highly polymorphic change all float vars to Double .." and it gives 4X performance improvement. I am interested in doing matrix computations in Haskell, should I make it a habit of writing highly monomorphic code? But some languages make good use of ad-hoc pol
我在回答这个SO问题时问这个问题。 Don stewart接受的答案：第一行说“你的代码是高度多态的，将所有float vars改为Double ..”，它提供了4倍的性能提升。 我有兴趣在Haskell中进行矩阵计算，我应该让它成为编写高度单形代码的习惯吗？ 但是有些语言很好地利用ad-hoc多态来生成快速代码，为什么GHC不会或者不会呢？ （读C ++或D） 为什么我们不能在Haskell中使用闪电++或特征？ 我不明白GHC中的类型类和（ad-hoc）多态是
I'm building an application which contains two components - server written in Haskell, and client written in Qt (C++). I'm using thrift to communicate them, and I wonder why is it working so slow. I made a performance test and here is the result on my machine Results C++ server and C++ client: Sending 100 pings - 13.37 ms Transfering 1000000 size vector -
我正在构建一个包含两个组件的应用程序 - 用Haskell编写的服务器，以及用Qt（C ++）编写的客户端。 我正在使用节俭来沟通它们，我想知道它为什么这么慢。 我做了性能测试，这是我机器上的结果 结果 C++ server and C++ client: Sending 100 pings - 13.37 ms Transfering 1000000 size vector - 433.58 ms Recieved: 3906.25 kB Transfering 100000 items from server - 1090.19 ms Transfe
I am a newer for C++, and my first language is Chinese, so my words with English may be unmeaningful, say sorry first. I know there is a way to write a function with variable parameters which number or type maybe different each calling, we can use the macros of va_list,va_start and va_end. But as everyone know, it is the C style. When we use the macros, we will lose the benefit of type-safe an
我是C ++的新手，我的第一语言是中文，所以我的英文单词可能是无意义的，首先抱歉。 我知道有一种方法可以编写一个可变参数的函数，每个调用的数字或类型可能不同，我们可以使用va_list，va_start和va_end的宏。 但是大家都知道，这是C风格。 当我们使用宏时，我们将失去类型安全和自动推理的好处，然后尝试使用它来处理C ++模板。 我的工作如下： #include<iostream> #include<vector> #include<boost/any.h