[syslinux] Isohybrid wiki page and UEFI

[Gene Cumm]

On Tue, Oct 27, 2015 at 10:15 PM, Bruno Cornec via Syslinux
<syslinux at zytor.com> wrote:
> Bruno Cornec via Syslinux said on Wed, Oct 28, 2015 at 01:45:22AM +0100:
>>
>> Is there a way to increase the debug level of syslinux.efi in order to
>> check what it tries to do and diagnose more precisely what happens ?
>
>
> Ok, I tried to modify mk/devel.mk to put:
> GCCWARN += -Wno-clobbered -DCORE_DEBUG=1 -DDEBUG_MALLOC -DDEBUG_THREAD
> And removing the -DDYNAMIC_DEBUG but now syslinux doesn't want to build:

MALLOC and THREAD are two debugs you probably don't want.

If you can capture the serial port and the firmware would allow it,
"-DDEBUG_PORT=0x3f8" would direct output to the first serial port.

"-DDEBUG_STDIO" may be useful but by the looks of it, not until after
ldlinux.* is loaded as printf()'s code isn't in the core but
ldlinux.*.

> ranlib liblpxelinux.a
> ld -m elf_i386  -Bsymbolic -pie -E --hash-style=gnu -T
> /root/syslinux/core/i386/syslinux.ld -M -o ldlinux.elf ldlinux.o \
>        --start-group libcom32.a --whole-archive
> /root/syslinux/bios/com32/lib/libcom32core.a libldlinux.a --end-group \
>                 > ldlinux.map
> libcom32.a(font.o): In function `SEG':
> /root/syslinux/com32/include/com32.h:144: undefined reference to `__bad_SEG'
> /root/syslinux/com32/include/com32.h:144: undefined reference to `__bad_SEG'
> libcom32.a(bios.o): In function `SEG':
> /root/syslinux/com32/include/com32.h:144: undefined reference to `__bad_SEG'
> /root/syslinux/com32/include/com32.h:144: undefined reference to `__bad_SEG'
> make[3]: *** [ldlinux.elf] Error 1
> make[3]: Leaving directory `/root/syslinux/bios/core
>
> It seems that the kaboom.c file is not compiled with the lib to define
> the function, but I'm absolutely unclear on what to do to fix this :-(

kaboom.c is in the core, not ldlinux.*.  I can't say I've ever seen this before.

-- 
-Gene