GCC, ARMboot - Creating standalone application without any library and any OS
arm, bootloader, c, embedded, gcc
Solution
I don't know that loader, but I think you should use objcopy like this to dump your executable data to a raw binary file. Don't jump to ELF headers, people :)
objcopy -O binary ./a.out o.bin
Also try to compile position independent code and to read ld and gcc manuals.
Problem
I have an embedded hardware system which contains a bootloader based on ARMboot (which is very similar to Uboot and PPCboot). This bootloader normally serves to load uClinux image from the flash. However, now I am trying to use this bootloader to run a standalone helloworld application, which does not require any linked library. Actually, it contains only `while(1){}` code in the main function. My problem is that I cannot find out what GCC settings should I use in order to build a standalone properly formatted binary. I do use following build command: ``` cr16-elf-gcc -o helloworld helloworld.c -nostdlib ``` which produces warning message: warning: cannot find entry symbol _start; defaulting to 00000004 Thereafter, within the bootloader, I upload a produced application and start it at some address: ``` tftpboot 0xa00000 helloworld go 0xa00004 ``` But it doesn't work :( The system reboots. Normally it should just hang (because of `while(1)`).