Help WIth Compiling Kernel Version 5.15.2

[not-ivy]

Kiss Linux Version: 2021.7-9
Kernel Version: 5.15.2

Commands run prior to compiling:

gzip -cd /proc/config.gz > .config
make localmodconfig # accepted all defaults
patch -p1 < /usr/share/doc/kiss/wiki/kernel/no-perl.patch
sed '/<stdlib.h>/a #include <linux/stddef.h>' tools/objtool/arch/x86/decode.c > _
mv -f _ tools/objtool/arch/x86/decode.c

Build Log:

~/linux-5.15.2 # make
  DESCEND objtool
  DESCEND bpf/resolve_btfids
  HOSTCXX scripts/gcc-plugins/structleak_plugin.so
diff: unrecognized option: I
BusyBox v1.34.1 (2021-11-13 07:16:57 UTC) multi-call binary.

Usage: diff [-abBdiNqrTstw] [-L LABEL] [-S FILE] [-U LINES] FILE1 FILE2

Compare files line by line and output the differences between them.
This implementation supports unified diffs only.

	-a	Treat all files as text
	-b	Ignore changes in the amount of whitespace
	-B	Ignore changes whose lines are all blank
	-d	Try hard to find a smaller set of changes
	-i	Ignore case differences
	-L	Use LABEL instead of the filename in the unified header
	-N	Treat absent files as empty
	-q	Output only whether files differ
	-r	Recurse
	-S	Start with FILE when comparing directories
	-T	Make tabs line up by prefixing a tab when necessary
	-s	Report when two files are the same
	-t	Expand tabs to spaces in output
	-U	Output LINES lines of context
	-w	Ignore all whitespace
Warning: Kernel ABI header at 'tools/arch/x86/include/asm/inat.h' differs from latest version at 'arch/x86/include/asm/inat.h'
diff -u tools/arch/x86/include/asm/inat.h arch/x86/include/asm/inat.h
diff: unrecognized option: I
BusyBox v1.34.1 (2021-11-13 07:16:57 UTC) multi-call binary.

Usage: diff [-abBdiNqrTstw] [-L LABEL] [-S FILE] [-U LINES] FILE1 FILE2

Compare files line by line and output the differences between them.
This implementation supports unified diffs only.

	-a	Treat all files as text
	-b	Ignore changes in the amount of whitespace
	-B	Ignore changes whose lines are all blank
	-d	Try hard to find a smaller set of changes
	-i	Ignore case differences
	-L	Use LABEL instead of the filename in the unified header
	-N	Treat absent files as empty
	-q	Output only whether files differ
	-r	Recurse
	-S	Start with FILE when comparing directories
	-T	Make tabs line up by prefixing a tab when necessary
	-s	Report when two files are the same
	-t	Expand tabs to spaces in output
	-U	Output LINES lines of context
	-w	Ignore all whitespace
Warning: Kernel ABI header at 'tools/arch/x86/include/asm/insn.h' differs from latest version at 'arch/x86/include/asm/insn.h'
diff -u tools/arch/x86/include/asm/insn.h arch/x86/include/asm/insn.h
diff: unrecognized option: I
BusyBox v1.34.1 (2021-11-13 07:16:57 UTC) multi-call binary.

Usage: diff [-abBdiNqrTstw] [-L LABEL] [-S FILE] [-U LINES] FILE1 FILE2

Compare files line by line and output the differences between them.
This implementation supports unified diffs only.

	-a	Treat all files as text
	-b	Ignore changes in the amount of whitespace
	-B	Ignore changes whose lines are all blank
	-d	Try hard to find a smaller set of changes
	-i	Ignore case differences
	-L	Use LABEL instead of the filename in the unified header
	-N	Treat absent files as empty
	-q	Output only whether files differ
	-r	Recurse
	-S	Start with FILE when comparing directories
	-T	Make tabs line up by prefixing a tab when necessary
	-s	Report when two files are the same
	-t	Expand tabs to spaces in output
	-U	Output LINES lines of context
	-w	Ignore all whitespace
Warning: Kernel ABI header at 'tools/arch/x86/lib/inat.c' differs from latest version at 'arch/x86/lib/inat.c'
diff -u tools/arch/x86/lib/inat.c arch/x86/lib/inat.c
diff: unrecognized option: I
BusyBox v1.34.1 (2021-11-13 07:16:57 UTC) multi-call binary.

Usage: diff [-abBdiNqrTstw] [-L LABEL] [-S FILE] [-U LINES] FILE1 FILE2

Compare files line by line and output the differences between them.
This implementation supports unified diffs only.

	-a	Treat all files as text
	-b	Ignore changes in the amount of whitespace
	-B	Ignore changes whose lines are all blank
	-d	Try hard to find a smaller set of changes
	-i	Ignore case differences
	-L	Use LABEL instead of the filename in the unified header
	-N	Treat absent files as empty
	-q	Output only whether files differ
	-r	Recurse
	-S	Start with FILE when comparing directories
	-T	Make tabs line up by prefixing a tab when necessary
	-s	Report when two files are the same
	-t	Expand tabs to spaces in output
	-U	Output LINES lines of context
	-w	Ignore all whitespace
Warning: Kernel ABI header at 'tools/arch/x86/lib/insn.c' differs from latest version at 'arch/x86/lib/insn.c'
diff -u tools/arch/x86/lib/insn.c arch/x86/lib/insn.c
In file included from scripts/gcc-plugins/gcc-common.h:103,
                 from scripts/gcc-plugins/structleak_plugin.c:32:
/usr/lib/gcc/x86_64-pc-linux-musl/11.2.0/plugin/include/builtins.h:23:10: fatal error: mpc.h: No such file or directory
   23 | #include <mpc.h>
      |          ^~~~~~~
compilation terminated.
make[2]: *** [scripts/gcc-plugins/Makefile:48: scripts/gcc-plugins/structleak_plugin.so] Error 1
make[1]: *** [scripts/Makefile.build:540: scripts/gcc-plugins] Error 2
make: *** [Makefile:1203: scripts] Error 2

Looks like mpc.h is missing, I tried rebuilding gcc and installing mpfr, but this error still appeared.
There are also multiple diff errors about the options, is there anything that I can do to fix that?

[not-ivy]

Update:
Installing libmpc solved the problem, but the diff error still exists, but I guess it doesn't matter since the kernel seems to compile ok.

[dylanaraps]

Read: #326

Also, the need for libmpc is something to do with your kernel configuration.