ld warning cannot find entry symbol _start defaulting to

[Lakshmipathi]

I'm compiling a simple helloworld program ,stuck in the final ld step

# ld -o hello hello.o -lc
ld: warning: cannot find entry symbol _start; defaulting to

I googled about this error message and found I would need to pass
/usr/lib/crt1.o /usr/lib/crti.o /usr/lib/crtn.o for runtime support.
(http://www.lisha.ufsc.br/teaching/os...ise/hello.html)

ld /usr/lib/crt1.o /usr/lib/crti.o -lc hello.o /usr/lib/crtn.o -o hello

But even after adding them , I'm unable to get the working binary.

Looking for help from LF members

[alex1983-0112]

Try that:

gcc -o hello hello.c

[Lakshmipathi]

Try that:

gcc -o hello hello.c

yes thanks,that's working fine ...but I need to create it using "ld" ...that's the issue.
I'm doing all compilation steps manually.Say first ran preprocessor (gcc -E ) then compilation (gcc -S ) and then assembler(gcc -c) and finally reached linker ..and stuck here

[Rubberman]

Once you have your .o files, you can still use gcc to link them to an executable. It will better deal with all the little cruft that needs to be passed to ld to create a viable executable.

[Lakshmipathi]

Thanks Rubberman, For academic purpose I was looking to create this binary ,seems like it's pretty hard to get ld working

[Rubberman]

The ld command can be very order dependent. And the startup code depends a great deal upon the language(s) used - such as C vs. C++, Fortran, et al. That's why I usually let gcc deal with that cruft. I do have to say that my wife uses ld a lot for the HEP (high energy physics) software she develops and maintains for Fermilab and CERN. Probably because they use a lot of different languages and systems. Sorry that I'm not being much help here...

[Lakshmipathi]

The ld command can be very order dependent.

Yes,a month ago when i tried ld first it didn't work. Then I changed the order of arguments in
ld command - it worked (Stupid me , I forgot the order - I tried to check .bash_history file ..but it is lost)...now in the process of documenting those steps ..somehow missed that vital ld part. anyway I'll search for it...

Sorry that I'm not being much help here...

No problem,thanks for help.