Re: How to develop a random number generation device

MooseFET wrote:
On Sep 12, 2:39 pm, David Brown
<david.br...@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
MooseFET wrote:
On Sep 11, 4:58 pm, John Larkin
<jjlar...@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
[... buffer overflow ...]
It sounds to me like C compilers/linkers tend to allocate memory to
code, buffers, and stack sort of anywhere they like.
It's up to the linker to build the segments, and the run-time
link-loader picks the addresses - the compiler is not involved in the
process.

I included the linker in the "compiler/linker" in many cases they are
the same program. In many environments the segments end up in memory
in the same order as they were in the file.


The linker is not the same program (for C) in any environment I have ever heard of - but it is generally *called* by the compiler automatically, so it just looks like it is part of the compiler. The point is, any linking issues are handled by linking directives and not by anything you give to the compiler (i.e., the source code).

The link-loader is a different animal altogether - it is what the operating system uses to actually load and run a program. It handles the final linking of the binary with any required run-time libraries, it allocates space and addresses for the different segments of the program, and it links the parts together. It is at that stage that the addresses are finalised. In particular, if you are using a system with randomised addresses, each time a program is loaded it is linked to a different random address.
.

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