#!/usr/bin/make -f
SHELL       :=/bin/sh
.SHELLFLAGS :=-efc
MAKEFLAGS   +=--no-print-directory

SRC = main.cc coreutils-sort.cc overlay.cc print.cc sort.cc xxhash.cc

CROSS ?=
CC    =$(CROSS)gcc
CXX   =$(CROSS)g++
STRIP =$(CROSS)strip

CFLAGS_LTO    ?=-flto=2 -fuse-linker-plugin -ffat-lto-objects -flto-partition=none
CFLAGS_COMMON ?=-O2 -g -fPIE -fstack-protector-strong
CFLAGS   ?=$(CFLAGS_COMMON) $(CFLAGS_LTO)
CPPFLAGS ?=-Wall -Wextra -Werror=format-security -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2
CXXFLAGS ?=$(CFLAGS_COMMON) $(CFLAGS_LTO) -std=gnu++20
LDFLAGS  ?=-Wl,-z,relro -Wl,-z,now -pie

NO_WARN = attributes class-memaccess unused-function unused-result
CPPFLAGS += $(foreach w,$(NO_WARN),-Wno-$(w))

NO_CXX = rtti exceptions
CXXFLAGS +=$(foreach f,$(NO_CXX),-fno-$(f))

OBJ = $(SRC:.cc=.cc.o)

.DEFAULT: all
.PHONY: all build clean
all build: overlaydirs

%.cc.o: %.cc
	$(CXX) -c $(CXXFLAGS) $(CPPFLAGS) -o $@ $^

overlaydirs: $(OBJ)
	$(CXX) $(CXXFLAGS) $(LDFLAGS) -o $@ $^ \
	$(if $(filter $(RELMODE),1),&& $(STRIP) --strip-debug --strip-unneeded $@)

clean:
	rm -f overlaydirs $(OBJ)