header-files

The tool include-what-you-use can be used to detect unneeded headers. I am using CMake for my C++ software project. How can I instruct CMake to run include-what-you-use automatically on the source files of my software project? CMake 3.3 introduced the new target property CXX_INCLUDE_WHAT_YOU_USE that can be set to the path of the program include-what-you-use . For instance this CMakeLists.txt cmake_minimum_required(VERSION 3.3 FATAL_ERROR) add_executable(hello main.cc) find_program(iwyu_path NAMES include-what-you-use iwyu) if(NOT iwyu_path) message(FATAL_ERROR "Could not find the program

How a standard library like libc.a (static library) which is included using #include <stdio.h> in our main.c differ from user defined header file (cube.h) included in main.c with its implementation file (cube.c) in C ? I mean both are header files but one's implementation is a static library (.a) and others is source file (.c) . You would have the definition (implementation) in, say, cube.c #include "cube.h" int cube( int x ) { return x * x * x; } Then we'll put the function declaration in another file. By convention, this is done in a header file, cube.h in this case. int cube( int x ); We

dir1 has dir2, file1.c and file1.h. dir2 has file2.c Now, if I want to access a function defined in file1.c in file2.c, I need to declare it in file1.h and include file1.h in file2.c -- is that a valid assumption? If no, please explain. If yes, even after doing that I am getting "undefined reference to function" error. file2.c:29: undefined reference to `function' collect2: ld returned 1 exit status * Error code 1 Compiling a c program happens in two steps basic steps: compiling and linking. Compiling turns source code into object code, and linking puts object code together, and ties all of

I'm trying to abstract out a method from a simple program. This method tests the length of an array against a predeclared CAPACITY constant, and spits out an error message if conditions aren't met. However, I'm having trouble creating a header file with a .cpp file to hold the method. the header file: //arrayHelper.h #ifndef ARRAYHELPER_H #define ARRAYHELPER_H void arrayLengthCheck(int & length, const int capacity, string prompt); #endif // ARRAYHELPER_H the code file: //arrayHelper.cpp #include <iostream> #include <string> #include "arrayHelper.h" using namespace std; void arrayLengthCheck

I am working on a library that I'm using in my other projects and I have the following header file: #pragma once #include <iostream> #include <map> #include "my_library/core/Structures.h" namespace My_Library { namespace NodeReaders { namespace HumanReadable { char charBuffer[256]; unsigned int uintBuffer; unsigned long long microsecondBuffer; unsigned int getNextUInt(std::istream & is) { /// Implementation } unsigned long getNextMicroseconds(std::istream & is) { /// Implementation } ... }; // namespace HumanReadable }; // namespace NodeReaders }; // namespace My_Library I've tried to include

I was playing around with namespaces when I encountered a lnk2005 error. I can't figure out how to get around the error. Here's the error: 1>Source.obj : error LNK2005: "int Chart::Bars::d" (?d@Bars@Chart@@3HA) already defined in Chart.obj 1>Source.obj : error LNK2005: "class foo Chart::l" (?l@Chart@@3Vfoo@@A) already defined in Chart.obj 1>Source.obj : error LNK2005: "int Chart::t" (?t@Chart@@3HA) already defined in Chart.obj 1>C:\Users\bnm\dev\examples\play\nmspca\Debug\nmspca.exe : fatal error LNK1169: one or more multiply defined symbols found 1> 1>Build FAILED. 1> 1>Time Elapsed 00:00:00