Hi Geert, On Mon, 2025-05-19 at 09:42 +0200, Geert Uytterhoeven wrote: > > AmigaOS doesn't use ELF though, it uses COFF. And Amiga Unix, which uses > > ELF, has a default alignment of 4 bytes as specified by the AT&T ABI. > > Initially Linux didn't use ELF either, but a.out.
Yes, the same applies for NetBSD. This also becomes obvious that the NetBSD header on m68k is called "netbsd-elf.h", instead of just "netbsd.h". > SunOS4 (based on BSD) did use 2-byte alignment on m68k, so I am still > surprised NetBSD didn't follow suit. When NetBSD still used a.out, it actually used 2 bytes alignment. They switched over when they switched from a.out to ELF, see: https://wiki.debian.org/M68k/Alignment > SunOS5 (based on SVR4) no longer supported m68k. True. I would now be really interested to find out what my Sony NEWS machines use on m68k. According to Wikipedia, it's based on SVR4, so I assume it uses ELF with 4 bytes alignment, see: https://en.wikipedia.org/wiki/UNIX_System_V#SVR4 There is also an Atari Unix which I would like to test as well. > I expect (the history of) the gcc sources would tell you more about > the default alignment on other (legacy UNIX) OSes supporting m68k... Good idea. I will do that. My assumption is that on Linux, GCC developers actually just forgot to switch alignment from 2 to 4 bytes with the switch to ELF unlike NetBSD. Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer `. `' Physicist `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
