[Round 2] Apply all source related changes for the new INSTALL.md in one commit.

libagbsyscall/Makefile

@@ -1,29 +1,28 @@
 TOOLCHAIN := $(DEVKITARM)
 COMPARE ?= 0
 
-ifeq ($(CC),)
-HOSTCC := gcc
-else
-HOSTCC := $(CC)
-endif
+# don't use dkP's base_tools anymore
+# because the redefinition of $(CC) conflicts
+# with when we want to use $(CC) to preprocess files
+# thus, manually create the variables for the bin
+# files, or use arm-none-eabi binaries on the system
+# if dkP is not installed on tihs system
 
-ifeq ($(CXX),)
-HOSTCXX := g++
-else
-HOSTCXX := $(CXX)
-endif
-
-ifneq (,$(wildcard $(TOOLCHAIN)/base_tools))
-include $(TOOLCHAIN)/base_tools
-else
+ifneq (,$(TOOLCHAIN))
+ifneq ($(wildcard $(TOOLCHAIN)/bin),)
 export PATH := $(TOOLCHAIN)/bin:$(PATH)
+endif
+endif
+
 PREFIX := arm-none-eabi-
 OBJCOPY := $(PREFIX)objcopy
-export CC := $(PREFIX)gcc
-export AS := $(PREFIX)as
-endif
-export CPP := $(PREFIX)cpp
-export LD := $(PREFIX)ld
+AS := $(PREFIX)as
+CPP := $(CC) -E
+LD := $(PREFIX)ld
+
+# note: the makefile must be set up so MODERNCC is never called
+# if MODERN=0
+MODERNCC := $(PREFIX)gcc
 
 ifeq ($(OS),Windows_NT)
 EXE := .exe