(ahgamut.github.io) Actually Portable Executables | Blog Needs a Name

ROAM_REFS: https://ahgamut.github.io/2021/02/27/ape-cosmo/

** Actually Portable Executables

I came across Cosmopolitan on Hacker News, and I was initially confused, due to a few memories of cross-compilation nightmares: while it should be possible to compile for the same architecture regardless of operating system, wouldn't the OS get confused by the leading bytes of the executable? I read the article explaining how it works, but most of it went over my head.

The example on the Github README used the following script for compilation:

gcc -g -O -static -nostdlib -nostdinc -fno-pie -no-pie -mno-red-zone   -o hello.com.dbg hello.c -fuse-ld=bfd -Wl,-T,ape.lds   -include cosmopolitan.h crt.o ape.o cosmopolitan.a
objcopy -S -O binary hello.com.dbg hello.com

I converted it into a simple Makefile to run the compilation commands. I tried a bunch of simple C programs (basic arithmetic, reading and writing to files) on Linux+Windows (compiled on Linux), and all of them worked.