rgbds: Parsing regression (?)

https://github.com/zzazzdzz/fools2018 compiles correctly with RGBDS 0.3.3, but errors out with 0.3.7:

ERROR: main.asm(7) -> main_sram2.asm(6) -> engine/text_engine.asm(369) -> includes/charset.asm(499):
    syntax error
error: Assembly aborted in pass 1 (1 errors)!

(Although the setup surrounding RGBDS is kinda hacky, this invocation should be completely vanilla.)