# Makefile for TCC on MontaukOS
# Copyright (c) 2026 Daniel Hammer

MAKEFLAGS += -rR
.SUFFIXES:

# ---- Toolchain ----

TOOLCHAIN_PREFIX := $(shell cd ../../.. && pwd)/toolchain/local/bin/x86_64-montauk-
ifeq ($(wildcard $(TOOLCHAIN_PREFIX)gcc),)
    CC = $(error x86_64-montauk toolchain not found. Run ./toolchain/build-montauk-toolchain.sh first)
    CXX = $(error x86_64-montauk toolchain not found. Run ./toolchain/build-montauk-toolchain.sh first)
    AR = $(error x86_64-montauk toolchain not found. Run ./toolchain/build-montauk-toolchain.sh first)
else
    CC  := $(TOOLCHAIN_PREFIX)gcc
    CXX := $(TOOLCHAIN_PREFIX)g++
    AR  := $(TOOLCHAIN_PREFIX)ar
endif

# ---- Paths ----

PROG_INC := ../../include
LIBDIR   := ../../lib
OBJDIR   := obj
BINDIR   := ../../bin/os

# ---- Compiler flags ----

CFLAGS := \
    -std=gnu11 \
    -g -O2 -pipe \
    -Wall \
    -Wno-unused-parameter \
    -Wno-unused-function \
    -Wno-sign-compare \
    -Wno-misleading-indentation \
    -Wno-implicit-fallthrough \
    -Wno-stringop-truncation \
    -Wno-format-truncation \
    -ffreestanding \
    -fno-stack-protector \
    -fno-stack-check \
    -ffunction-sections \
    -fdata-sections \
    -msse \
    -msse2 \
    -fno-tree-loop-distribute-patterns \
    -D__MONTAUKOS__=1 \
    -DONE_SOURCE=0 \
    -DTCC_TARGET_X86_64=1 \
    -DCONFIG_TCC_STATIC=1 \
    -I. \
    -isystem $(PROG_INC)/libc \
    -isystem $(shell $(CC) -print-file-name=include)

# -u _pf_putfloat forces liblibc.a's optional printf_float.o member to be
# linked: tcc formats floats when dumping constants (tccpp.c), and vsnprintf
# only references the float conversions weakly.
LDFLAGS := \
    -nostdlib \
    -Wl,--gc-sections \
    -Wl,-u,_pf_putfloat \
    -T ../../link.ld

# ---- Sources ----

TCC_SRCS := \
    libtcc.c \
    tccpp.c \
    tccgen.c \
    tccelf.c \
    tccasm.c \
    tccdbg.c \
    x86_64-gen.c \
    x86_64-link.c \
    i386-asm.c \
    tcc.c

COMPAT_SRCS := \
    montauk_main.c

ASM_SRCS := \
    setjmp.S

TCC_OBJS := $(patsubst %.c,$(OBJDIR)/%.o,$(TCC_SRCS))
COMPAT_OBJS := $(patsubst %.c,$(OBJDIR)/%.o,$(COMPAT_SRCS))
ASM_OBJS := $(patsubst %.S,$(OBJDIR)/%.o,$(ASM_SRCS))

ALL_OBJS := $(TCC_OBJS) $(COMPAT_OBJS) $(ASM_OBJS)

TARGET := $(BINDIR)/tcc.elf

# ---- CRT objects (staged from shared libc) ----

SHARED_CRT_DIR := $(LIBDIR)/libc
CRT_DIR := ../../bin/sdk/tcc/lib
CRT_OBJS := $(CRT_DIR)/crt1.o $(CRT_DIR)/crti.o $(CRT_DIR)/crtn.o

# ---- Rules ----

.PHONY: all clean

all: $(TARGET) $(CRT_OBJS) $(CRT_DIR)/libc.a

$(TARGET): $(ALL_OBJS) $(LIBDIR)/libc/liblibc.a
	@mkdir -p $(BINDIR)
	$(CC) $(CFLAGS) $(LDFLAGS) $(ALL_OBJS) $(LIBDIR)/libc/liblibc.a -lgcc -o $@

$(OBJDIR)/%.o: %.c Makefile config.h montauk_compat.h
	@mkdir -p $(OBJDIR)
	$(CC) $(CFLAGS) -MMD -MP -c $< -o $@

$(OBJDIR)/%.o: %.S Makefile
	@mkdir -p $(OBJDIR)
	$(CC) $(CFLAGS) -MMD -MP -c $< -o $@

$(SHARED_CRT_DIR)/liblibc.a $(SHARED_CRT_DIR)/liblibc-full.a $(SHARED_CRT_DIR)/crt1.o $(SHARED_CRT_DIR)/crti.o $(SHARED_CRT_DIR)/crtn.o:
	$(MAKE) -C $(SHARED_CRT_DIR)

$(CRT_DIR)/crt1.o: $(SHARED_CRT_DIR)/crt1.o
	@mkdir -p $(CRT_DIR)
	cp $< $@

$(CRT_DIR)/crti.o: $(SHARED_CRT_DIR)/crti.o
	@mkdir -p $(CRT_DIR)
	cp $< $@

$(CRT_DIR)/crtn.o: $(SHARED_CRT_DIR)/crtn.o
	@mkdir -p $(CRT_DIR)
	cp $< $@

# liblibc-full.a, not liblibc.a: programs compiled on-OS with tcc cannot pass
# -u _pf_putfloat, so this sysroot ships the variant with the printf float path
# already bound in. See lib/libc/Makefile.
$(CRT_DIR)/libc.a: $(LIBDIR)/libc/liblibc-full.a
	@mkdir -p $(CRT_DIR)
	cp $< $@

clean:
	rm -rf $(OBJDIR) $(TARGET)

# Auto-generated header dependency tracking (-MMD -MP).
-include $(TCC_OBJS:.o=.d) $(COMPAT_OBJS:.o=.d)
