Help with a makefile

[astrocrep]

Makefile:

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CC=gcc
CFLAGS=-Wall -O -fstrength-reduce -fomit-frame-pointer -finline-functions -nostdinc -fno-builtin -I./include -c -o
LD=ld
LDFLAGS=-T link.ld -o
ASM=nasm
ASMFLAGS=-f aout -o
SOURCES=start.asm main.c scrn.c gdt.c idt.c isrs.c irq.c timer.c kb.c
OBJS=start.o main.o scrn.o gdt.o idt.o isrs.o irq.o timer.o kb.o
EXECUTABLE=kernel32.sys

all: $(EXECUTABLE)

$(EXECUTABLE) : $(OBJECTS)
	$(LD) $(LDFLAGS) $(BUILDNAME) $(OBJS)
start.o : start.asm
	$(ASM) $(ASMFLAGS) start.o start.asm
main.o : main.c
	$(CC) $(CFLAGS) main.o main.c
scrn.o : scrn.c
	$(CC) $(CFLAGS) scrn.o scrn.c
gdt.o  : gdt.c
	$(CC) $(CFLAGS) gdt.o gdt.c
idt.o  : idt.c
	$(CC) $(CFLAGS) idt.o idt.c
isrs.o : isrs.c
	$(CC) $(CFLAGS) isrs.o isrs.c
irq.o  : irq.c
	$(CC) $(CFLAGS) irq.o irq.c
timer.o : timer.c
	$(CC) $(CFLAGS) timer.o timer.c
kb.o   : kb.c
	$(CC) $(CFLAGS) kb.o kb.c

If I do make all or make kernel32.sys it tells me ld fails cause it cannot find an object.

I can do make main.o and it runs fine. If all the .o's are build then it makes kernel32.sys fine...

Why doesn't it know to make the missing *.o files???

Thanks,
Rich

[B.E]

you got some variables that arnt defined (i.e spelt incorrectly):

replace

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$(EXECUTABLE) : $(OBJECTS) 

with

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$(EXECUTABLE) : $(OBJS) 

[astrocrep]

Ok, so I fixed that and it will build all of the .o files except for the ASM one.

When I type make the first thing I see is:

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nasm -f aout -o start.o start.asm

but no start.o is produced.

If I manually run the code above at the prompt it build the .o fine.

But make still fails all of the place because it cannot find the references help in start.o

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ld -Tlink.ld -o  start.o main.o scrn.o gdt.o idt.o isrs.o irq.o timer.o kb.o
ld: warning: cannot find entry symbol start; defaulting to 0000000000100000

Followed by a slew of other errors that are trying to find a couple of other things in start.o, mainly the isr handlers.

Thanks in advance.
Rich

[astrocrep]

Nevermind....

Another stupid bug in my makefile...
And a change to the nasm output to elf format...

Everything works!

and it boots perfect.

Thanks all!

-Rich

[Solar]

Another hint: Use ":=" instead of "=" if you define immutable lists. Variables defined by "=" have their contents evaluated every time they're used, while ":="-defined variables do so only once.