From eed3bb693b421a5d7b94ea8b6986d9cb7fcac56b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thomas=20Lov=C3=A9n?= <thomasloven@gmail.com>
Date: Fri, 2 Feb 2018 13:27:18 +0100
Subject: [PATCH] Commenting and cleanup

---
 Makefile            |  5 +++--
 src/kernel/Makefile | 11 ++++++-----
 toolchain/mkiso     |  2 ++
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/Makefile b/Makefile
index a5902cb..8dc1c4e 100644
--- a/Makefile
+++ b/Makefile
@@ -2,16 +2,17 @@ ifeq ($(MITTOS64),)
 $(error Unsupported environment! See README)
 endif
 
-.PHONY: kernel clean
+CC = x86_64-elf-gcc
 
 all: kernel
 
 kernel:
 ifeq ($(shell make -sqC src/kernel || echo 1), 1)
-	$(MAKE) -C src/kernel install
+	CC=$(CC) $(MAKE) -C src/kernel install
 endif
 
 clean:
 	$(MAKE) -C src/kernel clean
 	rm -rf sysroot
 
+.PHONY: kernel clean
diff --git a/src/kernel/Makefile b/src/kernel/Makefile
index a38f504..b44c048 100644
--- a/src/kernel/Makefile
+++ b/src/kernel/Makefile
@@ -2,12 +2,11 @@ ifeq ($(MITTOS64),)
 $(error Unsupported environment! See README)
 endif
 
-CC := x86_64-elf-gcc
-
 SRC := $(wildcard **/*.[cS])
 OBJ := $(patsubst %, %.o, $(basename $(SRC)))
 
-CFLAGS := -Wall -Wextra -pedantic -ffreestanding
+CFLAGS ?= -Wall -Wextra -pedantic
+CFLAGS += -ffreestanding
 CFLAGS += -ggdb -O0
 ASFLAGS += -ggdb
 CPPFLAGS += -I include
@@ -16,7 +15,8 @@ LDFLAGS := -n -nostdlib -lgcc -T Link.ld
 kernel: $(OBJ)
 	$(LINK.c) $^ -o $@
 
-
+# Automatically generate dependency files
+# Those keep track of which header files are used by which source files
 DEP := $(OBJ:.o=.d)
 DEPFLAGS = -MT $@ -MMD -MP -MF $*.d
 $(OBJ): CPPFLAGS += $(DEPFLAGS)
@@ -33,6 +33,7 @@ install: $(DESTDIR)$(PREFIX)/kernel
 clean:
 	rm -rf $(OBJ) $(DEP) kernel
 
-.PHONY: install
+.PHONY: install clean
 
+# Include generated dependency files
 include $(DEP)
diff --git a/toolchain/mkiso b/toolchain/mkiso
index 11d8a97..77f6c29 100755
--- a/toolchain/mkiso
+++ b/toolchain/mkiso
@@ -7,6 +7,8 @@ iso=${BUILDROOT}mittos64.iso
 
 mkdir -p ${sysroot}
 
+# Grub configuration file
+# set to boot /kernel with minimal wait
 mkdir -p ${sysroot}/boot/grub
 cat > ${sysroot}/boot/grub/grub.cfg << EOF
 set timeout=1