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1. #Rey seyfarth intro to 64 assembly for linux and os x download 64 Bit
2. #Rey seyfarth intro to 64 assembly for linux and os x download code

What isn't behaving the same is GDB's interpretation of what the stack is. The stack itself is behaving exactly the same - the processor doesn't care whether the program is a compiled C, or hand-written assembly. Why am I getting that last, seemingly garbage, output occasionally? Why is the stack not behaving similarly to in C? #4 0x00000000004011a8 in greater () at fact.asm:50Īnd then on the seventh call, this: (gdb) bt If I place the breakpoint on the line before calling the fact function ( dec rdi) then the result is usually this: (gdb) btīut on the fifth call of fact it's this: (gdb) bt In fact, the output from backtrace is really confusing me in this case.

#Rey seyfarth intro to 64 assembly for linux and os x download code

The code for the factorial function is like this - the breakpoint in this case is at the sub rsp, 16 line: fact: recursive function

#Rey seyfarth intro to 64 assembly for linux and os x download 64 Bit

Now I do the same in assembly (I've copied this code from Rey Seyfarth's book "Introduction to 64 bit assembly programming" so I am assuming it's correct) and, regardless of the depth of recursion, the stack frame looks like this: (Line 50 is the line call fact). My C code is like this: int factorial (int n) At the lowest level of recursion in a recursive factorial function, the stack frame looks like this: (This is a backtrace in gdb with a breakpoint at the first line of the function.) (gdb) bt

If I run some recursive code in C, the stack looks like I expect it to - an object on the stack for each call of the function. of China Hungary India Indonesia Ireland Israel Italy Jamaica Japan Kuwait Latvia Lithuania Luxembourg Macao S.A.R.I'm just learning about functions in assembly and the stack frame and so on, so I've been looking at the stack frame in gdb as I run a recursive algorithm to see what happens.