Makefile Portable POSIX Patterns

all: app

app: main.o util.o
  cc -o app main.o util.o

# Write simple, explicit file rules compatible with standard make.

CC = c99
CFLAGS = -O2
LDFLAGS =
LDLIBS =

app: main.o util.o
  $(CC) $(LDFLAGS) -o $@ main.o util.o $(LDLIBS)

# Honor user-overridable standard compiler variables.

.SUFFIXES: .c .o
.c.o:
  $(CC) $(CFLAGS) -c $<

# Use classic suffix rules when targeting very portable make implementations.

clean:
  rm -f app *.o

# Provide common non-file maintenance targets.

make CC=clang CFLAGS='-O0 -g'

# Allow users to customize toolchain choices.

deploy:
  cd infra && terraform apply -auto-approve

# Stop on failure explicitly within one recipe line.

print-pid:
  @echo $$PPID

# Pass `$` through to the shell.

target:
  printf 'hello
'

# Indent recipe commands with a tab character.

build:
  mkdir -p build

# Ensure output directories exist.

# Prefer explicit rules when portability matters
app: main.o util.o
  $(CC) -o $@ $^

# Prefer explicit rules over GNU metaprogramming.

SRC = main.c util.c api.c

# List sources explicitly or generate files in configure scripts.

release:
  cd dist && tar -czf app.tar.gz app

# Keep recipe-line semantics standard.