SDK v20.2.1

Bug fixes

• llvm-mos/llvm-mos#479 - Fixed linker crash when constant subtractions less than -128 are folded into zero page indexed addressing
  • 16-bit indexed addressing is used instead
  • This release also allows folding subtractions <= -128 into zero page indexed addressing, which the linker would previously disallow
• #378 - Fix odd behavior of atari minimal getchar by buffering a full line
  • atari's getchar requires a line to be read at a time without any intervening writes to the screen to operate correctly, but typical C practice does not expect interleaving putchar and getchar to interrupt the action of getchar.