Cross-language development

Dev Shed Forums Sponsor:

March 9th, 2003, 03:56 AM

M.Hirsch

Contributing User

Dev Shed God 1st Plane (5500 - 5999 posts)

Join Date: Oct 2000

Location: Back in the real world.

Posts: 5,966

Time spent in forums: 1 Month 2 Days 52 m 24 sec
Reputation Power: 189

Cross-language development

I am trying to move some of my Delphi code to C for speeding it up as time (and my boss) doesn´t allow porting the whole project.
I did something similar already years ago with Turbo Pascal and C, iirc then i linked the Pascal file against the C compiler´s .o file and i could use the functions. (It was Turbo C then, maybe this is why it did work?)

Now i am using Delphi and DevCPP (gcc 2.9x). What i am trying is:

Code:

Delphi:
program pTest_C_Lib;
{$APPTYPE CONSOLE}
{$LINK libtest.o}
function Test(m:Integer):Integer; stdcall; external 'libtest.o';

begin
  Test(10);
  Readln;
end.

And

Code:

C:
#include <stdio.h>
int test(int max) {
  int i;
  for (i=0;i<max;i++) {
    printf("Test %d",i);
  }
  return 0;
}

for testing. But when compiling, Delphi keeps telling me that the .o file is in the wrong format.
DevCPP is setup for making a static library. (i also get the libXXXXX.a file, but i have no idea how to import this to Delphi)

Am i doing something wrong or did things change so that this way is not possible anymore?

Do i really have to make a .DLL of it? (i don´t want to... but if you tell me that i have to, i will

)

Tia,
M.Hirsch

__________________
--
Manuel Hirsch - Linux, FreeBSD, programming, administration articles, tutorials and more.

March 9th, 2003, 02:45 PM

Scorpions4ever

Banned ;)

Dev Shed God 9th Plane (9000 - 9499 posts)

Join Date: Nov 2001

Location: Woodland Hills, Los Angeles County, California, USA

Posts: 9,406

Time spent in forums: 2 Months 10 h 20 m 32 sec
Reputation Power: 4080

>> I am trying to move some of my Delphi code to C for speeding it up as time (and my boss) doesn´t allow porting the whole project.
Can you just convince your boss that Delphi uses a Borland C++ compiler in the back-end. Delphi's compiler doesn't produce the fastest code ever, but it's not too bad. IIRC, Visual C++ and Intel's C++ compiler produce better optimized and faster code, but they take longer to compile as well.

IIRC most C compilers generate obj files in COFF format, but Delphi uses a different format for its obj files, so you can only use borland C++ and C++ builder (this info is old, so you may be able to use other compilers now). Anyways, here's a small tutorial on how to link C object files with delphi:
http://rvelthuis.bei.t-online.de/ar...icles-cobjs.htm

BTW, here are some links showing the relative performances of different C++ compilers (note that gcc 2.95 is known to be slower than gcc 3.x series) :
http://www.open-mag.com/754088105111.htm
http://www.coyotegulch.com/reviews/...gcc_bench1.html
http://www.realworldtech.com/page.c...RWT071302231228 <-- has delphi in the tests also.
http://www.willus.com/ccomp_benchmark.shtml

Hope this helps

Last edited by Scorpions4ever : March 9th, 2003 at 03:04 PM.

March 9th, 2003, 05:03 PM

M.Hirsch

Contributing User

Join Date: Oct 2000

Location: Back in the real world.

Posts: 5,966

Time spent in forums: 1 Month 2 Days 52 m 24 sec
Reputation Power: 189

Thank you very much.
I´ll try that tomorrow, tonight it´s already too late.

Scorpions, just in case you are interested - this is still the same project i asked for algorithms and other stuff earlier... my 3D engine. I have a hard time convincing my boss to convert to C because he also knows some basic delphi and he wants to "keep control" of the project

it´s not always logic that makes projects go the way they go... i fear it seldomly is...

i´m up to moving all speed critical functions to C (C++) now and use the STL as you suggested. Hope my collision detection routines will perform better then. If not, i still have the option of optimizing the C code which i can profile (i didn´t find a way yet to profile Delphi code...)

Next thing will be finding common data structures for C and Delphi. I´m already looking forward to this

but i have some links, so i am confident this will be done in a few hours...

I´ll convert to gcc3 soon, after i found out about the differences (i have some urls about that, just didn´t find the time yet to read.)

Again, thanks vm.
I´ll keep you up to date about my progress...

Cross-language development

Developer Shed Advertisers and Affiliates