Fence for Malloc'ed Memory Characterization

[Joel Sherrill]

Hi

Where is the memory fence for allocations added? How much? Does it adjoin
at the low and high end?

If I malloc(1), what does the layout look like?

    Low Fence of N bytes
    1 byte
    ??? Fence Filler
    High Fence of N bytes

When is it checked?

I didn't find the word fence in the manual and thus nothing characterizing
this.

Thanks.

--joel