sgdk-ssfmapper fails to link

[dleslie]

On 2f749a4f3547f9f4b06a2413f30d1efe53e526c6:

/home/dleslie/mars/m68k-elf/bin/m68k-elf-gcc -o out.elf -T /home/dleslie/mars/ldscripts/sgdk.ld -nostdlib boot/sega.o res/resources.o src/main.o   -L/home/dleslie/mars/m68k-elf/lib/gcc/m68k-elf/9.3.0 -lgcc -u __modsi3 -u __divsi3 -u __mulsi3 -u __umodsi3 -u __udivsi3 -u __umulsi3 -L/home/dleslie/mars/m68k-elf/lib -lmd-far
/home/dleslie/mars/m68k-elf/lib/gcc/m68k-elf/9.3.0/../../../../m68k-elf/bin/ld: boot/sega.o: in function `_EXTINT':
(.text.keepboot+0x44e): undefined reference to `internalExtIntCB'
/home/dleslie/mars/m68k-elf/lib/gcc/m68k-elf/9.3.0/../../../../m68k-elf/bin/ld: boot/sega.o: in function `_HINT':
(.text.keepboot+0x460): undefined reference to `internalHIntCB'
/home/dleslie/mars/m68k-elf/lib/gcc/m68k-elf/9.3.0/../../../../m68k-elf/bin/ld: boot/sega.o: in function `_VINT':
(.text.keepboot+0x472): undefined reference to `internalVIntCB'
collect2: error: ld returned 1 exit status

I compiled on WSL in an x86-64 ubuntu environment.