On 26 May 2025, at 15:05, Bjoern A. Zeeb <bzeeb-li...@lists.zabbadoz.net> wrote:
>
> On Mon, 26 May 2025, Dimitry Andric wrote:
>
> Hi,
>
> thanks for the quick answer.
>
>> On 26 May 2025, at 14:25, Bjoern A. Zeeb <bzeeb-li...@lists.zabbadoz.net>
>> wrote:
>>>
>>> I've just compiled and installed a new arm64/main with my own kernel
>>> config to have wifi bits as modules.
>>>
>>> I am a bit puzzed as to where this comes from in the kernel.
>>>
>>> # kldload wlan
>>> link_elf: symbol __floatundidf undefined: 0xffff000143ed1370
>>> 0xffff000143ecf9f0 11496 0xffff000143ed26d8 0x2
>>> kldload: can't load wlan: No such file or directory
>>>
>>> % nm modules/usr/src/sys/modules/wlan/wlan.ko.full | grep float
>>> U __floatundidf
>>>
>>> Anyone any idea?
>>
>> _Something_ is converting a unsigned long to a double, but what? Can you
>> figure out which object file it is?
>
> % nm ieee80211_ioctl.o | grep __floatundidf
> U __floatundidf
>
> This may be a local change I have adding an extra 10% of space in the
> ioctl code to accomodate for enlargement of a result set for testing.
> size_t space;
> ...
> space *= 1.10;
>
> Given it's likely that it's that I think the real question is, why is this
> not an issue on amd64 but on arm64 as I've been running that change for
> days on amd64?
My guess is that it's inlined on amd64. For me simple cases also inline on
arm64, but maybe you are doing something more complicated:
$ cat convert.c
#include <stddef.h>
size_t f(size_t s)
{
return s * 1.10;
}
$ cc -target aarch64-freebsd -S convert.c -o -
.text
.file "convert.c"
.section .rodata.cst8,"aM",@progbits,8
.p2align 3, 0x0 // -- Begin function f
.LCPI0_0:
.xword 0x3ff199999999999a // double 1.1000000000000001
.text
.globl f
.p2align 2
.type f,@function
f: // @f
.cfi_startproc
// %bb.0: // %entry
sub sp, sp, #16
.cfi_def_cfa_offset 16
str x0, [sp, #8]
ldr d0, [sp, #8]
ucvtf d0, d0
adrp x8, .LCPI0_0
ldr d1, [x8, :lo12:.LCPI0_0]
fmul d0, d0, d1
fcvtzu x0, d0
add sp, sp, #16
.cfi_def_cfa_offset 0
ret
.Lfunc_end0:
.size f, .Lfunc_end0-f
.cfi_endproc
// -- End function
.ident "FreeBSD clang version 19.1.7
(https://github.com/llvm/llvm-project.git llvmorg-19.1.7-0-gcd708029e0b2)"
.section ".note.GNU-stack","",@progbits
.addrsig
-Dimitry
