TASKING VX-toolset for ARM User Guide

TASKING VX-toolset for ARM User GuideC++ compiler option: --define (-D)Menu entry1. Select C/C++ Compiler » Preprocessing.The Defined symbols box shows the symbols that are currently defined.2. To define a new symbol, click on the Add button in the Defined symbols box.3. Type the symbol definition (for example, demo=1)Use the Edit and Delete button to change a macro definition or to remove a macro from the list.Command line syntax--define=macro_name[(parm-list)][=macro_definition]-Dmacro_name(parm-list)][=macro_definition]DescriptionWith this option you can define a macro and specify it to the preprocessor. If you only specify a macroname (no macro definition), the macro expands as '1'.Function-style macros can be defined by appending a macro parameter list to macro_name.You can specify as many macros as you like. Simply use the Add button to add new macro definitions.On the command line, you can use the option --define (-D) multiple times. If the command line exceedsthe limit of the operating system, you can define the macros in an option file which you then must specifyto the C++ compiler with the option --option-file (-f) file.The definition can be tested by the preprocessor with #if, #ifdef and #ifndef, for conditionalcompilations.ExampleConsider the following program with conditional code to compile a demo program and a real program:void main( void ){#if DEMOdemo_func(); /* compile for the demo program */#elsereal_func(); /* compile for the real program */#endif}You can now use a macro definition to set the DEMO flag:382