Click the OK button to close the Compiler settings window.

The C compiler should be either gcc or optionally gcc-8, the C++ compiler should be g++-8 and the Linker for dynamic libs should be g++-8.

button(s) which are marked by the mouse cursor in the below screenshot. It has already been selected in the below screenshot. Select Settings -> Compiler -> Global compiler settings (large blue gear icon in the left pane) -> Toolchain executables tab.sudo apt install gcc-8-base # recommended version Optionally install the latest version of gcc too (recommended). This is the command codeblocks that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator.

Install the latest version of the g++ compiler for C++. The C++ compiler is not configured for any version of g++ in Ubuntu 18.04 by default, so it has to be configured in the Code::Blocks compiler settings.

Your C++ program is not running in Code::Blocks because you do not have a C++ compiler (a version of G++) installed, or if it is installed you have not configured the C++ compiler in the Code::Blocks compiler settings.

Codeblocks compiler cannot open file