hi,

i tried to compile my c program with the option -m64 and got a warning as shown below..
> gcc -m64 file.c
cc1: sorry, not implemented: 64-bit mode not compiled in

i understood that 64-bit mode has to implemented while compiling the gcc source code.

Should i rebuild Gcc? if so which is the option to enable 64-bit mode..

Im using i686 athlon i386 GNU/Linux.. i hope kernel supports 64-bit mode.

thanks in advance
gobi

Good question. I'd

--> First, check the version of gcc. If it is less than 3.2 I guess even if you recompile it doesn't support 64-bit operations. If its newer than 3.2 than you might be lucky that it would already be compiled with that support.

--> An easy and quick test to check if your compiler supports 64 bit operations is to write a trivial C program. I've tested on my old laptop to find out that my gcc doesn't support 64 bit operations.

OK this is what I've done.

Wrote a test C program called test.c

void main()
{
printf("Hello\n");
}

And compiled it normally,

# gcc -o test32 test.c

It created a binary called test. To see if its a 32 bit binary, I used 'file'.
# file test32
test32: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.2.0, dynamically linked (uses shared libs), not stripped

Great, it is a 32-bit binary that can be executed on any i386 machine with Linux 2.2 or greater.

Then comes the big test, tried compiling as a 64-bit binary
#gcc -o test64 test.c -m64
cc1: sorry, not implemented: 64-bit mode not compiled in

If you don't get this error then you are probably fine. You can verify it using the 'file' command.

hi,
im using gcc 3.4.2

> gcc -v
Reading specs from /usr/lib/gcc/i386-redhat-linux/3.4.2/specs
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --disable-checking --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-java-awt=gtk --host=i386-redhat-linux
Thread model: posix
gcc version 3.4.2 20041017 (Red Hat 3.4.2-6.fc3)

when i do

> gcc -o check x.c
> file check

check: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.2.5, dynamically linked (uses shared libs), not stripped

> gcc -o check x.c -m64
x.c:1: sorry, unimplemented: 64-bit mode not compiled in

should i post anyother output?

Errrrh... is your FC 64 bit in the first bit, or did you install
a cross-compiler?


Cheers,
Tink

can you please tell me how to check whether FC3 is 64 bit ?

hi,
i just checked my FC3 version.. its 32-bit version of FC3..

> vi /proc/version

Linux version 2.4.20-8smp (bhcompile@stripples.devel.redhat.com) (gcc version 3.2.2 20030222 (Red Hat Linux 3.2.2-5)) #1 SMP Thu Mar 13 16:43:01 EST 2003

Im not using any cross compilers?

is it possible to generate 64-bit binary in 32-bit FC3 which runs on amd x86_64 machine?

i reinstalled FC for 64-bit version and it works now..
Thanks for all ur support..

Using the right things works wonders, doesn't it ;}


Cheers,
Tink