i686-elf-gcc error: cannot find crt0.o or -lc. help.

lordmilko / i686-elf-tools

i386-, i686- and x86_64-elf GCC, GDB and Binutils

MIT License

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i686-elf-gcc error: cannot find crt0.o or -lc. help. #24

Closed thatcppnerd closed 1 year ago

thatcppnerd commented 1 year ago

I'm (VERY) new to the os-dev scene, and have spent the past few days trying to find a cross-compiler to compile my kernel. When I first tested gcc I got the following error messages:

"bin/../lib/gcc/i686-elf/7.1.0/../../../../i686-elf/bin/ld: cannot find crt0.o: No such file or directory" "bin/../lib/gcc/i686-elf/7.1.0/../../../../i686-elf/bin/ld: cannot find -lc"

These just seem to be errors pertaining to the linker, but i'm still very confused.

I have made no modifications to my version thus far. Reinstall or find another compiler elsewhere?

lordmilko commented 1 year ago

Can you please provide some more information such as

What operating system you are using
Did you use the version found on the Releases page?
If so did you extract everything from the zip file? If on Windows, maybe right click the zip file -> Properties -> Unblock File before extracting
What is the command you are executing that is giving this error?

lordmilko commented 1 year ago

The fact it is looking for crt0 is very questionable to me, in an operating system there is no standard library, indicating you may not be specifying the correct arguments to gcc

Are you specifying -ffreestanding? Here is an example makefile that compiles assembly/C files using i686-elf-tools

thatcppnerd commented 1 year ago

Hello!

I am currently running Linux(Debian). Yes, I unzipped my files from i686-elf-tools-linux.zip The error was from a test of bin/i686-elf-gcc to see if everything was in order.

IDK if this helps, but the exact command executed was "bin/i686-elf-gcc test.c"

thatcppnerd commented 1 year ago

BTW, the mentioned test.c program: " int main() { int a = 0; } "

thatcppnerd commented 1 year ago

Yo!

Tested same command with -ffreestanding and -nostdlib and got an executable!

I think the issue was that I wasn't cross-compiling, but that's just my guess.

lordmilko commented 1 year ago

You cannot write an operating system by simply defining a main function. main is an illusion that is actually invoked by the CRT, which can have various names, but in this case will be called _start. To get started writing an operating system, I recommend reading the OSDev Wiki. Before you can even get to C you need to write a boot sector for your operating system using assembly. Once you have a boot sector and are ready to start writing the kernel portion in C, you will need to specify -ffreestanding to i686-elf-gcc

thatcppnerd commented 1 year ago

Thanks!