gcc optimization and stack allocation.

[Yang Ye]

Hi,

Do you have any idea on this scenario:
When gcc(3.3.3) allocating space for local varibles, e.g. a statement like 
'char buf[256];', the allocated buffers in stack always come with some 
space filled in at the end. If choose higher optimization level, let's say 
gcc -O6, the spaced filled at the end are smaller. I searched quite a lot 
documents, cannot find the official reason.

Yang Ye