Do calculation in the Makefile - shell

Question

I got confused with Makefile. I am trying to run a simple command in the Makefile but it gives me the error "/bin/bash: line 3: :=: command not found". I am using shell to run this makefile
This is my part of my Makefile:
all:
vlog Benchmarks/$(NAME)/Syn/*.v
$(eval tux_number := 1)
$(eval range := 1)
$(eval ssh_log := 255)
echo "Start Range: ${range}"
echo "tux-number: ${tux_number}"
while [[ $$range -le 50 ]] ; do \
ssh -l yazdanbakhsh tux-$(tux_number).cae.wisc.edu exit ; \
echo "range: ${range}" ; \
eval $$range := $$((${range}+1)) ; \
done
Thanks

Answer 1

all:
#range=1; \
while [ $$range -le 10 ] ; \
do echo Range: $$range; \
let range=range+1 ; \
done;
Note that the whitespace in front of #range... is the only TAB.

Answer 2

Just to fix your obvious problems with Makefile syntax, here is an attempt at refactoring your attempt into valid code.
tux_number := 1
ssh_log := 255 # not used anywhere
all:
vlog Benchmarks/$(NAME)/Syn/*.v
echo "Start Range: 1" # This is probably no longer very useful output
echo "tux-number: ${tux_number}"
range=1; while [ $$range -le 50 ] ; do \
ssh -l yazdanbakhsh tux-$(tux_number).cae.wisc.edu exit ; \
echo "range: $$range" ; \
range=$$(expr "$$range + 1); \
done
Notice how tux_number and ssh_log are Makefile variables, while range only exists in the shell which executes the while loop. I have avoided the Bashisms in order to make this portable. (If portability is not important, you might want to refactor it back to Bash syntax and use for ((range=1; range<=50; range++)); do... instead.)
Your use of eval is misguided. As you can see, I simply lifted out the Makefile variables outside the recipe where they don't belong. What you were doing was (1) have Make evaluate the expression range := 1 (which evaluates to itself) and (2) use the output as a shell command in a recipe. Since it's not a valid shell command, you got the syntax error from Bash. Without further ado, I'll just take the easy way out here and say that eval is a complex subject, and until you get more experience with Make, it's probably just best to forget that it exists.
In order to properly make use of Make's facilities, I would make this parallelizable, i.e. split it up into 50 individual targets. This is a bit clumsy (there's probably a better way to define range here), but at least it should illustrate a number of differences to your approach. (If you don't insist on having range count up from 1, making it zero-based would make this a little less clumsy. This exploits the fact that the empty string is harmless in a shell snippet, so we can use it instead of a zero prefix. Again, this could be simplifed if you don't care about the human readability of the range index.)
digits := 0 1 2 3 4 5 6 7 8 9
deca := "" 1 2 3 4
range := $(filter-out ""0,$(foreach d,$(deca),$(foreach i,$(digits),$d$i))) 50
# Or, at the expense of an external process,
# range := $(shell perl -le 'print $$_ for 1..50')
.PHONY: all
all: $(patsubst %,ssh-%,$(range))
.PHONY: ssh-%
ssh-%:
ssh -l yazdanbakhsh tux-$(tux_number).cae.wisc.edu exit
echo "range: $*"
This can be run with something like make -j 5 to execute these in parallel batches of five, for example.
Incidentally, the commented-out $(shell ...) call might be the actual answer to your question, if what you really wanted to do was to use Make to drive an external program to calculate something for you.