Linker limitations on 32-bit architectures

Posted Aug 27, 2019 22:24 UTC (Tue) by roc (subscriber, #30627)
In reply to: Linker limitations on 32-bit architectures by dezgeg
Parent article: Linker limitations on 32-bit architectures

> But the process-level emulation also has way more opportunities for bugs and weird behaviour.

Actually I would guess full-system emulation (i.e. running the native kernel) would be more likely to show bugs and weird behavior. The CPU+hardware behavior exposed to the kernel is a lot more complicated and less well tested in general than that exposed to user-space.

> For example, if a shell script run under qemu-arm-static runs `cat /proc/cpuinfo` to check for some CPU capabilities, what will happen? Does QEMU have the smarts to notice that a read() system call is being made for /proc/cpuinfo and substitute some emulated values for some ARM CPU, or will it just read the /proc/cpuinfo from the host machine resulting in values for some x86 cpu?

That is a good question. Issues like that could be fixed outside QEMU by running the process in a chroot environment. You may be doing that for cross-compilation anyway.