Hello world does work in PE but not in PE64

Asked Feb 08 '16 at 19:08

Active Feb 08 '16 at 19:54

Viewed 197 times

I'm trying to kind of write my own x64 Hello world program in FASM on Windows I tried to rewrite this version: How to write to the console in fasm?, to a x64 program like this:

format PE64

entry start

include 'win64a.inc'

section '.code' code readable executable
start:
    push hello
    call [printf]
    pop rcx

    push 0
    call [ExitProcess]

section '.rdata' data readable
    hello db 'Hello world!', 10, 0

section '.idata' import data readable writeable
    library kernel,'KERNEL32.DLL', \
        msvcrt,'msvcrt.dll'
    import kernel, ExitProcess,'ExitProcess'
    import msvcrt, printf, 'printf'

Now the problem is that this compiles fine, but when it is executed it doesn't print anything to the console.

Why does this not work, is printf of msvcrt silently incompatible with x64? Have I overseen something?

Can someone tell me how to rewrite this for it to actually print "Hello world!"?

edited May 23 '17 at 12:07

Community

asked Feb 08 '16 at 19:08

S.Klumpers

Parameters (the first 4 anyway) are not passed through the stack like that in the WIN64 calling conventions – harold Feb 08 '16 at 19:48
I edited the question. How can I rewrite the program, should I pass 4 dummies or something? – S.Klumpers Feb 08 '16 at 19:53
The first param goes in `rcx`, no push/pop should be necessary here – harold Feb 08 '16 at 19:57
Thank you, this does indeed work. – S.Klumpers Feb 08 '16 at 20:22

Hello world does work in PE but not in PE64

0 Answers0