gcc vs vc++: Calling data as code

[sidster]

Greetings,

I think the attached source does what you ask.  Seems to work on my
linux box.



% gcc -v
Reading specs from /usr/lib/gcc-lib/i386-slackware-linux/egcs-2.91.66/specs
gcc version egcs-2.91.66 19990314/Linux (egcs-1.1.2 release)

% uname -a
Linux 3eye 2.2.13 #3 Sun Dec 26 02:14:38 PST 1999 i686 unknown




* Robert Feldt (feldt@ce.chalmers.se) [20000724 23:42]:
[...] 
> My friend has an application were machine code is manipulated in buffers
> and then called as code. Here's the challenge and my first effort to solve
> it:
> 
> Challenge: Implement the functions f1 and f2 below without writing
> them in C code, ie. by having their machine code in a buffer and
> calling it. Since his interest is in the Wintel architecture it does
> not need to work on other machines/architectures.
> 
> float f1(float* in) {
>   return in[0] + in[1];
> }
> 
> float out[2];
> 
> void f2(float* in1, float* in2) {
>   out[0] = in[0] + in2[0];
>   out[1] = in[1] - in1[1];
> }
[...]



Best regards,

patrick
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