Static libraries increase the size of the code in your binary. They’re always loaded and whatever version of the code you compiled with is the version of the code that will run. Dynamic libraries are stored and versioned separately. It’s possible for a version of the dynamic library to be loaded that wasn’t the original … Read more
This ensures that resolution occurs from the global namespace, instead of starting at the namespace you’re currently in. For instance, if you had two different classes called Configuration as such: class Configuration; // class 1, in global namespace namespace MyApp { class Configuration; // class 2, different from class 1 function blah() { // resolves … Read more
For iterating backwards see this answer. Iterating forwards is almost identical. Just change the iterators / swap decrement by increment. You should prefer iterators. Some people tell you to use std::size_t as the index variable type. However, that is not portable. Always use the size_type typedef of the container (While you could get away with … Read more
The “STL” was written by Alexander Stepanov in the days long before C++ was standardised. C++ existed through the 80s, but what we now call “C++” is the language standardised in ISO/IEC 14882:2014 (and earlier versions, such as ISO/IEC 14882:2011). The STL was already widely used as a library for C++, giving programmers access to … Read more
The GCC FAQ has an entry on it: The solution is to ensure that all virtual methods that are not pure are defined. Note that a destructor must be defined even if it is declared pure-virtual [class.dtor]/7. Therefore, you need to provide a definition for the virtual destructor: virtual ~CDasherModule() { }
Placement new allows you to construct an object in memory that’s already allocated. You may want to do this for optimization when you need to construct multiple instances of an object, and it is faster not to re-allocate memory each time you need a new instance. Instead, it might be more efficient to perform a … Read more
First example std::vector<int> return_vector(void) { std::vector<int> tmp {1,2,3,4,5}; return tmp; } std::vector<int> &&rval_ref = return_vector(); The first example returns a temporary which is caught by rval_ref. That temporary will have its life extended beyond the rval_ref definition and you can use it as if you had caught it by value. This is very similar to … Read more
The compilation of a C++ program involves three steps: Preprocessing: the preprocessor takes a C++ source code file and deals with the #includes, #defines and other preprocessor directives. The output of this step is a “pure” C++ file without pre-processor directives. Compilation: the compiler takes the pre-processor’s output and produces an object file from it. … Read more
Use the -S option to gcc (or g++), optionally with -fverbose-asm which works well at the default -O0 to attach C names to asm operands as comments. Less well at any optimization level, which you normally want to use to get asm worth looking at. gcc -S helloworld.c This will run the preprocessor (cpp) over … Read more