GCC's assembly output of an empty program on x86, win32

Question

I write empty programs to annoy the hell out of stackoverflow coders, NOT. I am just exploring the gnu toolchain.

Now the following might be too deep for me, but to cont

Answer 1

Regarding that andl $-16,%esp

• 32 bits: -16 in decimal equals to 0xfffffff0 in hexadecimal representation
• 64 bits: -16 in decimal equals to 0xfffffffffffffff0 in hexadecimal representation

So it will mask off the last 4 bits of ESP (btw: 2**4 equals to 16) and will retain all other bits (no matter if the target system is 32 or 64 bits).