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Generic Makefile not working on FreeBSD

Please note that this is not a duplicate of the other questions named generic makefile.

I have followed all of the instructions on other questions about generic makefiles, and this is the code I have come up with from that:

CFLAGS = -c
CC = cc
SOURCES = $(wildcard *.cc)
OBJECTS = $(patsubst %.cc,%.o,%(SOURCES))
EXEC = run

all: build clean

build: $(OBJECTS)
    $(CC) $(OBJECTS) -o $(EXEC)

%.o: %.cc
    $(CC) $(CFLAGS) $<

clean:
    rm *.o

However, when I execute make with a file called test.cc in my directory, it gives me the followig error:

cc    -o run
cc: error: no input files
*** Error code 1

Stop.
make: stopped in /somewhere

Please note that I am on FreeBSD and the make and cc commands are the ones which come with the OS.

like image 985
Ethan McTague Avatar asked Feb 01 '15 14:02

Ethan McTague


2 Answers

The lines

SOURCES = $(wildcard *.cc)
OBJECTS = $(patsubst %.cc,%.o,%(SOURCES))

are GNU make syntax, not understood by FreeBSD's make, which has its own dialect (specifically $(wildcard) and $(patsubst)). If you need to write makefiles portable to many systems, either require gmake to exist and use GNUmakefiles, or stick to the features of POSIX make.

You can install GNU make (gmake) on FreeBSD with

cd /usr/ports/devel/gmake
make install clean
like image 132
Jens Avatar answered Sep 28 '22 14:09

Jens


In FreeBSD's make, you can do it like this:

SOURCES!= ls *.cc
OBJECTS = ${SOURCES:.cc=.o}

The first line uses a variable assignment modifier. Expand the value and pass it to the shell for execution and assign the result to the variable. Any newlines in the result are replaced with spaces. This is a very powerfull mechanism. You should e.g. use find instead of ls to also search in subdirectories;

SOURCES!= find . -type f -name '*.cc'

The second line uses a variable modifier to perform AT&T System V UNIX style variable substitution. It replaces the suffix .cc with the .o suffix.

like image 20
Roland Smith Avatar answered Sep 28 '22 14:09

Roland Smith