The Differences in Data Representation

Machines of different architectures represent data differently internally.

Simple example: integers

On Sun-SPARC or Motorola PowerPC architectures integers are stored as

while on Intel x86 processors, integers are stored as

So the integer 1 on a SPARC or PowerPC would be interpreted as the integer 16777216 (2²⁴) on the Intel.

Other problems occur with respect to alignment and pointers:

• Different alignment schemes will cause the data in structures to be stored differently.
• Pointers have no meaning outside the program where they are used.