gcc 32bit/ 64bit 컴파일하기

나중에 리눅스 서버 하나 다시 만들어서 해봐야지

These -m switches are supported in addition to the above on AMD x86-64 processors in 64-bit environments. -m32 -m64 Generate code for a 32-bit or 64-bit environment. The 32-bit environment sets int, long and pointer to 32 bits and generates code that runs on any i386 system. The 64-bit environment sets int to 32 bits and long and pointer to 64 bits and generates code for AMD's x86-64 architecture.  [링크 : https://gcc.gnu.org/onlinedocs/gcc-3.1/gcc/i386-and-x86-64-Options.html]

64bit 우분투에서 빌드 하려니 에러가 발생한다. multilib을 설치하라는데..

$ gcc -m32 void.c In file included from /usr/include/stdio.h:28:0,                  from void.c:1: /usr/include/features.h:324:26: fatal error: bits/predefs.h: No such file or directory compilation terminated.

$ sudo apt-get install gcc-multilib [링크 : http://uce.uniovi.es/tips/Programming/Cpp/forc32bitscompilation.html]  [링크 : http://stackoverflow.com/questions/22355436/how-to-compile-32-bit-apps-on-64-bit-ubuntu]