From Ogre Wiki

For those migrating from Code::Blocks + MinGW + STLPort to Code::Blocks + MinGW, the following instructions should help make the switch easier.

Contents 1 MinGW C++ Toolbox install Guide 2 Code::Blocks Compiler / debugger settings 3 Project build options changes

MinGW C++ Toolbox install Guide

Read the MinGW Toolbox Install Guide.

Code::Blocks Compiler / debugger settings

You must tell Code::Blocks where you installed the MinGW C++ Toolbox by following these instructions here: Code Blocks Compiler Setup

Project build options changes

used for both Debug and Release target build options:

• Compiler
  • Other options
    • no changes required
  • '#defines'
    • remove _STLP_NO_CUSTOM_IO and _STLP_USE_DYNAMIC_LIB
      
• Linker
  • Other linker options:
    • no changes required
• Directories
  • Compiler
    • remove $(OGRE_HOME)\stlport\stlport
  • Linker
    • No changes required
• Build targets
  • for debug build targets compiler defines remove the define: _STLP_DEBUG

After you make the changes to the your project settings you must do a rebuild so that everything gets recompiled with the proper headers.