How to Compile 32-bit Program on 64-bit GCC in C++

To compile a 32-bit program on a 64-bit GCC (GNU Compiler Collection) in C++, you’ll need to specify the -m32 flag to indicate that you want to generate 32-bit code. Additionally, you may need to install 32-bit development libraries if they are not already installed on your system. Here are the steps to compile a 32-bit program:

1. Install 32-bit Development Libraries (if needed):
   Depending on your Linux distribution, you may need to install the 32-bit development libraries. These libraries are necessary for linking and running 32-bit programs. The package names may vary depending on your distribution. Here are some common package names:

• On Ubuntu/Debian: sudo apt-get install gcc-multilib g++-multilib
• On CentOS/RHEL:
  bash sudo yum install glibc-devel.i686 libstdc++-devel.i686

1. Write your C++ program or have it ready.
2. Compile the program with the -m32 flag to generate 32-bit code:

 g++ -m32 -o my_program my_program.cpp

Replace my_program with your desired output binary name and my_program.cpp with the name of your source code file.

4. Run your 32-bit program:

 ./my_program

This will compile and run your C++ program as a 32-bit executable on a 64-bit system using GCC. Please note that the availability of 32-bit libraries and the -m32 flag may vary depending on your specific Linux distribution and GCC version. Make sure to install the necessary packages and flags accordingly.