compile checksums?

[me22]

2009/9/8 Paul Boyle <paulcboyle@gmail.com>:
>
> Hopefully someone on this thread can help me. Every time I compile any
> source code that includes 'iostream' is  results in different
> assembler. Does anyone know what the underline reason for this is? Is
> this a known characteristic, or is there a known way of working around
> this? I need to develop a mechanism to guarantee that builds from
> source code generate identical binaries and was planing to use the
> binaries' checksum, but this characteristic is preventing this.
>

From GCC's man page:

       -frandom-seed=string
           This option provides a seed that GCC uses when it would otherwise
           use random numbers.  It is used to generate certain symbol names
           that have to be different in every compiled file.  It is also used
           to place unique stamps in coverage data files and the object files
           that produce them.  You can use the -frandom-seed option to produce
           reproducibly identical object files.

           The string should be different for every file you compile.

HTH,
~ Scott McMurray