Bad 'undefined symbol' error when using with GNU assembler or GCC

[MasterofGalaxies]

When a string or other data is referenced in the same source file where it is defined, Kamek will throw an undefined symbol error:

$ cat returnstring.s
lis 3, string@h
ori 3, 3, string@l
blr
string:
.string "string"
$ powerpc-eabi-as -o returnstring.o returnstring.s
$ Kamek returnstring.o -static=0x80001900 -output-riiv=returnstring.xml
Kamek 2.0 by Ninji/Ash Wolf - https://github.com/Treeki/Kamek

adding returnstring.o as object..
linking version default...

Unhandled Exception:
System.IO.InvalidDataException: undefined symbol 
  at Kamek.Linker.ResolveSymbol (Kamek.Elf elf, System.String name) [0x00110] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.ProcessRelaSection (Kamek.Elf elf, Kamek.Elf+ElfSection relocs, Kamek.Elf+ElfSection section, Kamek.Elf+ElfSection symtab) [0x000cc] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.ProcessRelocations () [0x00149] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.DoLink (System.Collections.Generic.Dictionary`2[TKey,TValue] externalSymbols) [0x0008d] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.LinkStatic (System.UInt32 baseAddress, System.Collections.Generic.Dictionary`2[TKey,TValue] externalSymbols) [0x00019] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Program.Main (System.String[] args) [0x004a5] in <84417af72b3544ac8bfbaa14b20da809>:0 
[ERROR] FATAL UNHANDLED EXCEPTION: System.IO.InvalidDataException: undefined symbol 
  at Kamek.Linker.ResolveSymbol (Kamek.Elf elf, System.String name) [0x00110] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.ProcessRelaSection (Kamek.Elf elf, Kamek.Elf+ElfSection relocs, Kamek.Elf+ElfSection section, Kamek.Elf+ElfSection symtab) [0x000cc] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.ProcessRelocations () [0x00149] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.DoLink (System.Collections.Generic.Dictionary`2[TKey,TValue] externalSymbols) [0x0008d] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Linker.LinkStatic (System.UInt32 baseAddress, System.Collections.Generic.Dictionary`2[TKey,TValue] externalSymbols) [0x00019] in <84417af72b3544ac8bfbaa14b20da809>:0 
  at Kamek.Program.Main (System.String[] args) [0x004a5] in <84417af72b3544ac8bfbaa14b20da809>:0

This does not occur when using CodeWarrior, or when the string and the code that references it are in separate files and combined with ld:

$ cat returnstring-1.s
lis 3, string@h
ori 3, 3, string@l
blr
$ cat returnstring-2.s
string:
.string "string"
$ powerpc-eabi-as -o returnstring-1.o returnstring-1.s
$ powerpc-eabi-as -o returnstring-2.o returnstring-2.s
$ powerpc-eabi-ld --relocatable -o returnstring.o returnstring-1.o returnstring-2.o
$ Kamek returnstring.o -static=0x80001900 -output-riiv=returnstring.xml
Kamek 2.0 by Ninji/Ash Wolf - https://github.com/Treeki/Kamek

adding returnstring.o as object..
linking version default...
$ cat returnstring.xml
<memory offset='0x80001900' value='3C6080006063190C4E800020737472696E670000' />

Partial fix

Change line 392 of Kamek/Linker.cs to:

Word dest = (String.IsNullOrEmpty(symName) ? _sectionBases[section] : ResolveSymbol(elf, symName).address) + r_addend;

I don't know how to find the section the data is in, so this will only work if the data and the code that references it are in the same section.

[RoadrunnerWMC]

The readme states that there's no plan to ever support any compilers other than CodeWarrior, so I doubt that Ninji (Treeki) would consider this behavior a bug.

[MasterofGalaxies]

I'm aware of that and the reasons Kamek can't be used with C++ and other compilers, but there's no reason C can't be used, and the fix for this is probably really simple for someone familiar with the code.

[RoadrunnerWMC]

I just talked with Ninji about it on Discord, and he agreed with you that this would probably be reasonable to fix. I don't know how to fix it myself, but I'll leave the issue open.

[MasterofGalaxies]

That's awesome. This bug can be really annoying. Thanks!

[RoadrunnerWMC]

Fixed by #36.