Example to write string in UTF-8 encoded source file but tell compiler to store string in SJIS

build.sh

#!/bin/sh

arm-none-eabi-gcc -S test.c

# https://gcc.gnu.org/onlinedocs/cpp/Invocation.html#index-fexec-charset
arm-none-eabi-gcc -S test.c -o test_sjis.s -fexec-charset=sjis

test.c

const char s[] = "ああ";

test.s

	.cpu arm7tdmi
	.eabi_attribute 20, 1
	.eabi_attribute 21, 1
	.eabi_attribute 23, 3
	.eabi_attribute 24, 1
	.eabi_attribute 25, 1
	.eabi_attribute 26, 1
	.eabi_attribute 30, 6
	.eabi_attribute 34, 0
	.eabi_attribute 18, 4
	.file	"test.c"
	.text
	.global	s
	.section	.rodata
	.align	2
	.type	s, %object
	.size	s, 7
s:
	.ascii	"\343\201\202\343\201\202\000"
	.ident	"GCC: (15:9-2019-q4-0ubuntu1) 9.2.1 20191025 (release) [ARM/arm-9-branch revision 277599]"

test_sjis.s

	.cpu arm7tdmi
	.eabi_attribute 20, 1
	.eabi_attribute 21, 1
	.eabi_attribute 23, 3
	.eabi_attribute 24, 1
	.eabi_attribute 25, 1
	.eabi_attribute 26, 1
	.eabi_attribute 30, 6
	.eabi_attribute 34, 0
	.eabi_attribute 18, 4
	.file	"test.c"
	.text
	.global	s
	.section	.rodata
	.align	2
	.type	s, %object
	.size	s, 5
s:
	.ascii	"\202\240\202\240\000"
	.ident	"GCC: (15:9-2019-q4-0ubuntu1) 9.2.1 20191025 (release) [ARM/arm-9-branch revision 277599]"