Merge pull request rh-hideout#1999 from leo60228/nixos-install

Fix build on NixOS and add instructions to INSTALL.md

INSTALL.md

@@ -354,6 +354,13 @@ Then proceed to [Choosing where to store pokeemerald (Linux)](#choosing-where-to
 >   [install devkitARM on Arch Linux](#installing-devkitarm-on-arch-linux).
 </details>
 
+### NixOS
+Run the following command to start an interactive shell with the necessary packages:
+```bash
+nix-shell -p pkgsCross.arm-embedded.stdenv.cc git pkg-config libpng
+```
+Then proceed to [Choosing where to store pokeemerald Expansion (Linux)](#choosing-where-to-store-pokeemerald-expansion-linux).
+
 ### Other distributions
 _(Specific instructions for other distributions would be greatly appreciated!)_
 

Makefile

@@ -73,7 +73,7 @@ MODERN_ELF_NAME := $(MODERN_ROM_NAME:.gba=.elf)
 MODERN_MAP_NAME := $(MODERN_ROM_NAME:.gba=.map)
 MODERN_OBJ_DIR_NAME := build/modern
 
-SHELL := /bin/bash -o pipefail
+SHELL := bash -o pipefail
 
 ELF = $(ROM:.gba=.elf)
 MAP = $(ROM:.gba=.map)

asmdiff.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 if [[ -d "$DEVKITARM/bin/" ]]; then
     OBJDUMP_BIN="$DEVKITARM/bin/arm-none-eabi-objdump"