• We already know the first thing that happens is that the
  C preprocessor scans the source form of the program and
  produces a new source file with all the preprocessor
  directives removed, macros expanded, include files
  included in the source file, etc.

• This modified version of the source file is then passed to
  the C compiler to produce the object form of the program,
  if the name of the source file is xxx.c then the name of the
  object file will be xxx.o

• The .o file contains relocatable machine language--that is,
  there is enough information in the .o file to place the
  machine language code anywhere in the address space of
  the machine

• The next process is loading or link editing the program

LOADING

• The program ld performs the loading of your C
  program, the input to this program is a collection of .o
  files and libraries and the output is an executable program

• You usually don't invoke ld directly, the C compiler can
  do it for you - the C compiler knows the special libraries
  and startup code that is required for C programs, you
  don't need to remember this stuff

March 3, 1998

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