Bug#1057462: syslinux: FTBFS: error: ‘-fcf-protection’ is not compatible with this target

Just some notes on this bug:

Ubuntu addressed it with the following patch:
https://git.launchpad.net/ubuntu/+source/syslinux/commit/?h=applied/ubuntu/noble&id=4828eee42000655782c9e1ccaa5d56333dd3d44f

After applying the patch, the build fails later with:
---
/.. -fcommon -W -Wall -Wstrict-prototypes  -Wpointer-arith -Wwrite-strings -Wstrict-prototypes -Winline -DDYNAMIC_CRC_TABLE -mregparm=3 -DREGPARM=3 -c -o syslinux/debug.o /home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/lib/syslinux/debug.c
/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/lib/syslinux/debug.c: In function ‘syslinux_debug’:
/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/lib/syslinux/debug.c:91:5: error: implicit declaration of function ‘printf’ [-Wimplicit-function-declaration]
   91 |     printf("Dynamic debug unavailable\n");
      |     ^~~~~~
/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/lib/syslinux/debug.c:4:1: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
    3 | #include <stdbool.h>
  +++ |+#include <stdio.h>
    4 |
/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/lib/syslinux/debug.c:91:5: warning: incompatible implicit declaration of built-in function ‘printf’ [-Wbuiltin-declaration-mismatch]
   91 |     printf("Dynamic debug unavailable\n");
      |     ^~~~~~
/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/lib/syslinux/debug.c:91:5: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
make[6]: *** [/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/mk/lib.mk:215: syslinux/debug.o] Error 1
make[6]: Leaving directory '/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/bios/com32/lib'
make[5]: *** [/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/com32/Makefile:8: lib] Error 2
make[5]: Leaving directory '/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/bios/com32'
make[4]: *** [/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/Makefile:288: com32] Error 2
make[4]: Leaving directory '/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/bios'
make[3]: *** [/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1/Makefile:257: bios] Error 2
make[3]: Leaving directory '/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1'
make[2]: *** [Makefile:102: bios] Error 2
make[2]: Leaving directory '/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1'
make[1]: *** [debian/rules:17: override_dh_auto_build-arch] Error 2
make[1]: Leaving directory '/home/bob/syslinux-6.04~git20190206.bf6db5b4+dfsg1'
make: *** [debian/rules:14: build] Error 2
dpkg-buildpackage: error: debian/rules build subprocess returned exit status 2
---

Fixing that as suggested by including stdio.h in debug.c, it again fails with the behavior described here:
https://lore.kernel.org/all/[email protected]/T/

After applying that patch and additionally applying:
https://git.launchpad.net/ubuntu/+source/syslinux/commit/?h=applied/ubuntu/noble&id=6423519171fe0d3bcee92f653cba750a74769264

From here on, I'm kind of lost. Hopefully, that helps someone.

Cheers,
Thomas Duetsch