# ww — Plan 9-organised toolchain. POSIX make.
#
# Build a small static frontend library libwcc.a and the user-facing
# driver `ww`. Per-target tools (w6c, w6a, w6l) and the runtime are added
# in their own phases. Everything lands under out/.

PREFIX	?= /usr/local
CC	?= cc
AR	?= ar
CFLAGS	?= -O0 -g -Wall -Wextra -Wpedantic -Wno-unused-parameter
CFLAGS	+= -std=c99 -fno-strict-aliasing -D_POSIX_C_SOURCE=200809L
INCS	= -Icmd/wcc

OUT	= out
BIN	= $(OUT)/bin
LIB	= $(OUT)/lib
OBJ	= $(OUT)/obj

WCC_SRC	= cmd/wcc/mem.c cmd/wcc/err.c cmd/wcc/tok.c cmd/wcc/lex.c \
	  cmd/wcc/ast.c cmd/wcc/parse.c cmd/wcc/sym.c cmd/wcc/type.c \
	  cmd/wcc/check.c
WCC_OBJ	= $(WCC_SRC:cmd/wcc/%.c=$(OBJ)/wcc/%.o)

WW_SRC	= cmd/ww/main.c
WW_OBJ	= $(WW_SRC:cmd/ww/%.c=$(OBJ)/ww/%.o)

WD_SRC	= cmd/wwdump/main.c
WD_OBJ	= $(WD_SRC:cmd/wwdump/%.c=$(OBJ)/wwdump/%.o)

W6C_SRC	= cmd/w6c/main.c cmd/w6c/cgen.c cmd/w6c/txt.c cmd/w6c/swt.c \
	  cmd/w6c/peep.c cmd/w6c/reg.c
W6C_OBJ	= $(W6C_SRC:cmd/w6c/%.c=$(OBJ)/w6c/%.o)

W6A_SRC	= cmd/w6a/main.c cmd/w6a/lex.c cmd/w6a/parse.c cmd/w6a/asm.c cmd/w6a/obj.c
W6A_OBJ	= $(W6A_SRC:cmd/w6a/%.c=$(OBJ)/w6a/%.o)

W6L_SRC	= cmd/w6l/main.c cmd/w6l/obj.c cmd/w6l/sym.c cmd/w6l/pass.c cmd/w6l/out.c \
	  cmd/w6l/dyn.c cmd/w6l/dynout.c
W6L_OBJ	= $(W6L_SRC:cmd/w6l/%.c=$(OBJ)/w6l/%.o)

RT_S	= rt/start.s rt/syscall.s rt/alloc.s rt/streq.s rt/abort.s
RT_OBJ	= $(RT_S:rt/%.s=$(OBJ)/rt/%.o)

# Cstage: one-time C bootstrap (see BOOTSTRAP.md). Built by `cc`.
# Goes away at v1.0, replaced by a checked-in stage-0 binary.
CSTAGE_BINS	= $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l $(BIN)/wwdump

# Wwstage: ww-rewritten toolchain. Built by Cstage today; will be the
# only toolchain after Phase 10 closeout. Byte-identical to Cstage
# (tests 990-994).
WWSTAGE_BINS	= $(BIN)/wwdump_ww $(BIN)/w6c_ww $(BIN)/w6a_ww $(BIN)/w6l_ww $(BIN)/ww_ww

BINS	= $(CSTAGE_BINS) $(WWSTAGE_BINS)
LIBS	= $(LIB)/libwcc.a $(LIB)/libwwrt.a

all: cstage wwstage

cstage: $(CSTAGE_BINS) $(LIBS)
wwstage: $(WWSTAGE_BINS)

# ---- libwcc.a ----------------------------------------------------------
$(LIB)/libwcc.a: $(WCC_OBJ) | $(LIB)
	$(AR) rcs $@ $(WCC_OBJ)

$(OBJ)/wcc/%.o: cmd/wcc/%.c cmd/wcc/ww.h | $(OBJ)/wcc
	$(CC) $(CFLAGS) $(INCS) -c -o $@ $<

# ---- ww driver ---------------------------------------------------------
$(BIN)/ww: $(WW_OBJ) $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $(WW_OBJ) -L$(LIB) -lwcc

$(OBJ)/ww/%.o: cmd/ww/%.c cmd/wcc/ww.h | $(OBJ)/ww
	$(CC) $(CFLAGS) $(INCS) -c -o $@ $<

# ---- wwdump (lex/AST diff anchor) --------------------------------------
$(BIN)/wwdump: $(WD_OBJ) $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $(WD_OBJ) -L$(LIB) -lwcc

$(OBJ)/wwdump/%.o: cmd/wwdump/%.c cmd/wcc/ww.h | $(OBJ)/wwdump
	$(CC) $(CFLAGS) $(INCS) -c -o $@ $<

# ---- w6c amd64 compiler ------------------------------------------------
$(BIN)/w6c: $(W6C_OBJ) $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $(W6C_OBJ) -L$(LIB) -lwcc

$(OBJ)/w6c/%.o: cmd/w6c/%.c cmd/w6c/gc.h cmd/w6c/6.out.h cmd/wcc/ww.h | $(OBJ)/w6c
	$(CC) $(CFLAGS) $(INCS) -Icmd/w6c -c -o $@ $<

# ---- w6a amd64 assembler -----------------------------------------------
$(BIN)/w6a: $(W6A_OBJ) | $(BIN)
	$(CC) $(CFLAGS) -o $@ $(W6A_OBJ)

$(OBJ)/w6a/%.o: cmd/w6a/%.c cmd/w6a/a.h cmd/w6c/6.out.h | $(OBJ)/w6a
	$(CC) $(CFLAGS) -Icmd/w6a -Icmd/w6c -c -o $@ $<

# ---- w6l amd64 linker --------------------------------------------------
$(BIN)/w6l: $(W6L_OBJ) | $(BIN)
	$(CC) $(CFLAGS) -o $@ $(W6L_OBJ)

$(OBJ)/w6l/%.o: cmd/w6l/%.c cmd/w6l/l.h | $(OBJ)/w6l
	$(CC) $(CFLAGS) -Icmd/w6l -c -o $@ $<

# ---- ww-side wwdump (the lexer port, exercised by 990_selfhost) --------
# Built via the user-facing ww driver. The introspection ports (lex,
# tok, ast, parse, typ, sym) live in lib/ww/; the compiler-only bits
# (mem, check, cgen*) stay in selfhost/cmd/wcc/. Output named wwdump_ww
# to avoid colliding with the C-side wwdump in $(BIN).
$(BIN)/wwdump_ww: selfhost/cmd/wwdump/main.ww \
		lib/ww/lex.ww lib/ww/tok.ww lib/ww/ast.ww \
		lib/ww/parse.ww lib/ww/typ.ww lib/ww/sym.ww \
		selfhost/cmd/wcc/mem.ww selfhost/cmd/wcc/check.ww \
		selfhost/cmd/wcc/cgen.ww selfhost/cmd/wcc/cgen_expr.ww \
		selfhost/cmd/wcc/cgen_stmt.ww selfhost/cmd/wcc/cgen_util.ww \
		selfhost/cmd/wcc/cgen_decl.ww \
		lib/os/os.ww lib/strconv/strconv.ww \
		$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a | $(BIN)
	cd $(BIN) && ./ww build \
		-I $$PWD/../../lib/ww \
		-I $$PWD/../../selfhost/cmd/wcc \
		$$PWD/../../selfhost/cmd/wwdump/main.ww
	mv $(BIN)/main $@

# ---- ww-side w6c (compiler port, exercised by 994_w6c_ww) -------------
# Thin driver: parse + cgen. The frontend (lex/parse/ast/...) lives in
# lib/ww/; cgen + check live in selfhost/cmd/wcc/.
$(BIN)/w6c_ww: selfhost/cmd/w6c/main.ww \
		lib/ww/lex.ww lib/ww/tok.ww lib/ww/ast.ww \
		lib/ww/parse.ww lib/ww/typ.ww lib/ww/sym.ww \
		selfhost/cmd/wcc/mem.ww selfhost/cmd/wcc/check.ww \
		selfhost/cmd/wcc/cgen.ww selfhost/cmd/wcc/cgen_expr.ww \
		selfhost/cmd/wcc/cgen_stmt.ww selfhost/cmd/wcc/cgen_util.ww \
		selfhost/cmd/wcc/cgen_decl.ww \
		lib/os/os.ww \
		$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a | $(BIN)
	cd $(BIN) && ./ww build \
		-I $$PWD/../../lib/ww \
		-I $$PWD/../../selfhost/cmd/wcc \
		$$PWD/../../selfhost/cmd/w6c/main.ww
	mv $(BIN)/main $@

# ---- ww-side w6a (assembler port, exercised by 991_w6a_ww) ------------
# Built like wwdump_ww. Needs -I selfhost/cmd/w6a for the local types/lex/
# parse/asm/obj modules and -I selfhost/cmd/wcc to find `mem`.
$(BIN)/w6a_ww: selfhost/cmd/w6a/main.ww selfhost/cmd/w6a/types.ww \
		selfhost/cmd/w6a/lex.ww selfhost/cmd/w6a/parse.ww \
		selfhost/cmd/w6a/asm.ww selfhost/cmd/w6a/obj.ww \
		selfhost/cmd/wcc/mem.ww \
		lib/os/os.ww \
		$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a | $(BIN)
	cd $(BIN) && ./ww build \
		-I $$PWD/../../selfhost/cmd/w6a \
		-I $$PWD/../../selfhost/cmd/wcc \
		$$PWD/../../selfhost/cmd/w6a/main.ww
	mv $(BIN)/main $@

# ---- ww-side w6l (linker port, exercised by 992_w6l_ww) ---------------
# Built like 6a_ww. Needs -I selfhost/cmd/w6l for the local sym/obj/pass/
# out modules and -I selfhost/cmd/wcc to find `mem`.
$(BIN)/w6l_ww: selfhost/cmd/w6l/main.ww selfhost/cmd/w6l/sym.ww \
		selfhost/cmd/w6l/obj.ww selfhost/cmd/w6l/dyn.ww \
		selfhost/cmd/w6l/pass.ww selfhost/cmd/w6l/dynout.ww \
		selfhost/cmd/w6l/out.ww selfhost/cmd/wcc/mem.ww \
		lib/os/os.ww \
		$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a | $(BIN)
	cd $(BIN) && ./ww build \
		-I $$PWD/../../selfhost/cmd/w6l \
		-I $$PWD/../../selfhost/cmd/wcc \
		$$PWD/../../selfhost/cmd/w6l/main.ww
	mv $(BIN)/main $@

# ---- ww-side ww driver (exercised by 993_ww_ww) ------------------------
# The driver pulls in lib/os (default search path) and selfhost/cmd/wcc
# (for the bump arena). It then orchestrates w6c/w6a/w6l like the C driver.
$(BIN)/ww_ww: selfhost/cmd/ww/main.ww selfhost/cmd/wcc/mem.ww lib/os/os.ww \
		$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a | $(BIN)
	cd $(BIN) && ./ww build \
		-I $$PWD/../../selfhost/cmd/wcc \
		$$PWD/../../selfhost/cmd/ww/main.ww
	mv $(BIN)/main $@

# ---- runtime (libwwrt.a, assembled by our own w6a) ---------------------
$(OBJ)/rt/%.o: rt/%.s $(BIN)/w6a | $(OBJ)/rt
	$(BIN)/w6a -o $@ $<

$(LIB)/libwwrt.a: $(RT_OBJ) | $(LIB)
	$(AR) rcs $@ $(RT_OBJ)

# ---- directories -------------------------------------------------------
$(BIN) $(LIB) $(OBJ)/wcc $(OBJ)/ww $(OBJ)/wwdump $(OBJ)/w6c $(OBJ)/w6a $(OBJ)/w6l $(OBJ)/rt:
	mkdir -p $@

# ---- tests -------------------------------------------------------------
# Each phase adds a $(BIN)/test_<name> target; the runner walks them.
TESTS	= $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
	  $(BIN)/test_w6c $(BIN)/test_w6a $(BIN)/test_w6l $(BIN)/test_arch \
	  $(BIN)/test_e2e $(BIN)/test_ffi $(BIN)/test_dyn $(BIN)/test_stdlib \
	  $(BIN)/test_selfhost $(BIN)/test_w6a_ww $(BIN)/test_w6l_ww \
	  $(BIN)/test_w6c_ww $(BIN)/test_ww_ww $(BIN)/test_self_rebuild \
	  $(BIN)/test_dyn_ww

$(BIN)/test_smoke: test/wcc/000_smoke.c $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) $(INCS) -o $@ $< -L$(LIB) -lwcc

$(BIN)/test_lex: test/wcc/100_lex.c $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) $(INCS) -o $@ $< -L$(LIB) -lwcc

$(BIN)/test_parse: test/wcc/200_parse.c $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) $(INCS) -o $@ $< -L$(LIB) -lwcc

$(BIN)/test_check: test/wcc/300_check.c $(LIB)/libwcc.a | $(BIN)
	$(CC) $(CFLAGS) $(INCS) -o $@ $< -L$(LIB) -lwcc

$(BIN)/test_w6c: test/wcc/400_w6c.c $(BIN)/w6c | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_w6a: test/wcc/500_w6a.c $(BIN)/w6c $(BIN)/w6a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_w6l: test/wcc/600_w6l.c $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_arch: test/wcc/610_arch.c $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(OBJ)/rt/start.o | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_e2e: test/wcc/700_e2e.c $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a $(OBJ)/rt/start.o | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_ffi: test/wcc/800_ffi.c $(BIN)/w6c | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_dyn: test/wcc/810_dyn.c $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(LIB)/libwwrt.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_stdlib: test/wcc/900_stdlib.c $(BIN)/w6c | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_selfhost: test/wcc/990_selfhost.c $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
		$(BIN)/ww $(BIN)/wwdump $(BIN)/wwdump_ww $(LIB)/libwwrt.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_w6a_ww: test/wcc/991_w6a_ww.c $(BIN)/w6a $(BIN)/w6a_ww | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_w6l_ww: test/wcc/992_w6l_ww.c $(BIN)/w6l $(BIN)/w6l_ww \
		$(LIB)/libwwrt.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_w6c_ww: test/wcc/994_w6c_ww.c $(BIN)/w6c_ww $(BIN)/wwdump_ww | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_ww_ww: test/wcc/993_ww_ww.c $(BIN)/ww $(BIN)/ww_ww \
		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_self_rebuild: test/wcc/995_self_rebuild.c $(BIN)/ww_ww \
		$(BIN)/w6c_ww $(BIN)/w6a_ww $(BIN)/w6l_ww $(BIN)/wwdump_ww \
		$(LIB)/libwwrt.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

$(BIN)/test_dyn_ww: test/wcc/996_dyn_ww.c $(BIN)/ww $(BIN)/w6l $(BIN)/w6l_ww \
		$(LIB)/libwwrt.a | $(BIN)
	$(CC) $(CFLAGS) -o $@ $<

test: all $(TESTS)
	@WW=$(BIN)/ww BIN=$(BIN) sh test/run

install: all
	mkdir -p $(PREFIX)/bin $(PREFIX)/lib
	cp $(BIN)/ww $(PREFIX)/bin/
	cp $(LIB)/libwcc.a $(PREFIX)/lib/

clean:
	rm -rf $(OUT)

# ---- bootstrap (phase 10) ----------------------------------------------
# Four-stage self-host: Cstage (these C tools) → ww1 → ww2 → ww3 → ww4
# with cmp ww2 == ww3 and cmp ww3 == ww4. Stage 1 is wwdump_ww (the
# ww-built frontend); stages 2/3/4 assemble with w6a_ww and link with
# w6l_ww — every tool below the driver is now in ww. The C `ww` driver
# still orchestrates the pipeline (porting it is the remaining phase-10
# work).
#
# Why a fourth stage? Stage 3 proves ww1 and ww2 (which differ in how
# they were built) emit the same machine code. Stage 4 proves ww3 is
# byte-stable when used as a compiler — i.e. the fixed point is truly
# fixed, not merely a coincidental two-stage equilibrium.
BS	= $(OUT)/bootstrap
bootstrap: all
	@echo "=== stage 0 (Cstage): C-built tools ==="
	@echo "  $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l"
	@echo
	@echo "=== stage 1: ww-built tools, used to drive stages 2/3/4 ==="
	@ls -l $(BIN)/wwdump_ww $(BIN)/w6a_ww $(BIN)/w6l_ww $(BIN)/ww_ww
	@rm -rf $(BS) && mkdir -p $(BS)
	@echo
	@echo "=== stage 2: ww2 = ww1 self-compiles main.combined.ww ==="
	@$(BIN)/wwdump_ww -c selfhost/cmd/wwdump/main.combined.ww > $(BS)/ww2.s
	@$(BIN)/w6a_ww -o $(BS)/ww2.o $(BS)/ww2.s
	@$(BIN)/w6l_ww -o $(BS)/ww2 $(BS)/ww2.o $(LIB)/libwwrt.a
	@ls -l $(BS)/ww2
	@echo
	@echo "=== stage 3: ww3 = ww2 self-compiles main.combined.ww ==="
	@$(BS)/ww2 -c selfhost/cmd/wwdump/main.combined.ww > $(BS)/ww3.s
	@$(BIN)/w6a_ww -o $(BS)/ww3.o $(BS)/ww3.s
	@$(BIN)/w6l_ww -o $(BS)/ww3 $(BS)/ww3.o $(LIB)/libwwrt.a
	@ls -l $(BS)/ww3
	@echo
	@echo "=== stage 4: ww4 = ww3 self-compiles main.combined.ww ==="
	@$(BS)/ww3 -c selfhost/cmd/wwdump/main.combined.ww > $(BS)/ww4.s
	@$(BIN)/w6a_ww -o $(BS)/ww4.o $(BS)/ww4.s
	@$(BIN)/w6l_ww -o $(BS)/ww4 $(BS)/ww4.o $(LIB)/libwwrt.a
	@ls -l $(BS)/ww4
	@echo
	@echo "=== fixed-point gates ==="
	@cmp $(BS)/ww2.s $(BS)/ww3.s && echo "  ww2.s == ww3.s ✓"
	@cmp $(BS)/ww2.o $(BS)/ww3.o && echo "  ww2.o == ww3.o ✓ (byte-identical .o)"
	@cmp $(BS)/ww2 $(BS)/ww3 && echo "  ww2 == ww3 ✓ (byte-identical exe)"
	@cmp $(BS)/ww3.s $(BS)/ww4.s && echo "  ww3.s == ww4.s ✓"
	@cmp $(BS)/ww3.o $(BS)/ww4.o && echo "  ww3.o == ww4.o ✓ (byte-identical .o)"
	@cmp $(BS)/ww3 $(BS)/ww4 && echo "  ww3 == ww4 ✓ (byte-identical exe, ww3 is byte-stable as a compiler)"
	@echo
	@echo "BOOTSTRAP OK: ww-cgen + w6a_ww + w6l_ww reach a fixed point that holds across two iterations."
	@echo
	@echo "Phase 10 remaining work:"
	@echo "  - delete cmd/wcc/ cmd/w6c/ cmd/w6a/ cmd/w6l/ cmd/ww/ in the final commit"
	@echo
	@echo "Already in selfhost/:"
	@echo "  - cmd/wcc/ : ww-cgen  (lex/parse/check/cgen) — bootstrap fixed point"
	@echo "  - cmd/w6c/ : ww-w6c   (lex/parse/cgen front-end) — matches wwdump_ww -c (test 994)"
	@echo "  - cmd/w6a/ : ww-w6a   (lex/parse/asm/obj) — byte-identical to C w6a (test 991)"
	@echo "  - cmd/w6l/ : ww-w6l   (linker w/ archive support) — byte-identical to C w6l (test 992)"
	@echo "  - cmd/ww/  : ww-driver (build/run/version) — byte-identical to C ww (test 993)"

# ---- nocc: bootstrap from a checked-in stage-0 binary, no cc -----------
# A fresh-checkout flow that never invokes cc. Mirrors `make bootstrap`'s
# fixed-point check but uses `bootstrap/$(ARCH)/{ww,w6c,w6a,w6l}` as the
# starting point and lands in $(OUT)/nocc/ so the cstage build under
# $(OUT)/ stays untouched. See bootstrap/README.md and BOOTSTRAP.md.
#
# `make bootstrap-snapshot` populates bootstrap/$(ARCH)/ from the
# currently-built wwstage so you can verify locally before deciding
# to commit the binaries.
ARCH		?= amd64
STAGE0		= bootstrap/$(ARCH)
NOCC_OUT	= $(OUT)/nocc
NOCC_BIN	= $(NOCC_OUT)/bin
NOCC_LIB	= $(NOCC_OUT)/lib
NOCC_OBJ	= $(NOCC_OUT)/obj

bootstrap-snapshot: wwstage
	@mkdir -p $(STAGE0)
	@cp $(BIN)/ww_ww $(STAGE0)/ww
	@cp $(BIN)/w6c_ww $(STAGE0)/w6c
	@cp $(BIN)/w6a_ww $(STAGE0)/w6a
	@cp $(BIN)/w6l_ww $(STAGE0)/w6l
	@echo "snapshot: $(STAGE0)/{ww,w6c,w6a,w6l} populated from $(BIN)/*_ww"
	@echo "         (gitignored — 'git add -f bootstrap/$(ARCH)/*' to ship)"

nocc:
	@for f in ww w6c w6a w6l; do \
		test -x $(STAGE0)/$$f || { \
			echo "$@: missing $(STAGE0)/$$f"; \
			echo "$@: run 'make bootstrap-snapshot' first, or read bootstrap/README.md"; \
			exit 1; \
		}; \
	done
	@echo "=== nocc: starting from $(STAGE0) (no cc invoked) ==="
	@rm -rf $(NOCC_OUT)
	@mkdir -p $(NOCC_BIN) $(NOCC_LIB) $(NOCC_OBJ)
	@# Stage 0: drop bootstrap binaries under both natural names and
	@# the _ww-suffixed names the driver expects when shelling out.
	@for f in ww w6c w6a w6l; do \
		cp $(STAGE0)/$$f $(NOCC_BIN)/$$f; \
		cp $(STAGE0)/$$f $(NOCC_BIN)/$${f}_ww; \
	done
	@# Assemble libwwrt.a using stage-0 w6a — the linker needs it for
	@# every wwstage-built binary in the next stage. Member order
	@# follows $(RT_S) so the embedded symbol table matches the
	@# cstage-built libwwrt.a (cstage uses ar rcs $(RT_OBJ), same
	@# order).
	@objs=""; for s in $(RT_S); do \
		b=`basename $$s .s`; \
		$(NOCC_BIN)/w6a -o $(NOCC_OBJ)/$$b.o $$s; \
		objs="$$objs $(NOCC_OBJ)/$$b.o"; \
	done; $(AR) rcs $(NOCC_LIB)/libwwrt.a $$objs
	@echo "=== stage 1: stage-0 rebuilds the wwstage tools from source ==="
	@# The driver's default lib path is $self_dir/../../lib — under
	@# $(NOCC_BIN) that resolves to $(NOCC_OUT)/lib (libwwrt only).
	@# Pass -I $(CURDIR)/lib so `use os` etc. resolve to source.
	@cd $(NOCC_BIN) && ./ww build \
		-I $(CURDIR)/lib/ww \
		-I $(CURDIR)/selfhost/cmd/wcc \
		-I $(CURDIR)/lib $(CURDIR)/selfhost/cmd/w6c/main.ww && mv main w6c_ww1
	@cd $(NOCC_BIN) && ./ww build -I $(CURDIR)/selfhost/cmd/w6a \
		-I $(CURDIR)/selfhost/cmd/wcc -I $(CURDIR)/lib \
		$(CURDIR)/selfhost/cmd/w6a/main.ww && mv main w6a_ww1
	@cd $(NOCC_BIN) && ./ww build -I $(CURDIR)/selfhost/cmd/w6l \
		-I $(CURDIR)/selfhost/cmd/wcc -I $(CURDIR)/lib \
		$(CURDIR)/selfhost/cmd/w6l/main.ww && mv main w6l_ww1
	@cd $(NOCC_BIN) && ./ww build -I $(CURDIR)/selfhost/cmd/wcc \
		-I $(CURDIR)/lib $(CURDIR)/selfhost/cmd/ww/main.ww && mv main ww_ww1
	@echo "=== fixed-point gates: rebuilt tools == stage-0 binaries? ==="
	@cmp $(NOCC_BIN)/w6c_ww1 $(STAGE0)/w6c && echo "  w6c ✓"
	@cmp $(NOCC_BIN)/w6a_ww1 $(STAGE0)/w6a && echo "  w6a ✓"
	@cmp $(NOCC_BIN)/w6l_ww1 $(STAGE0)/w6l && echo "  w6l ✓"
	@cmp $(NOCC_BIN)/ww_ww1 $(STAGE0)/ww && echo "  ww ✓"
	@echo
	@echo "NOCC OK: $(STAGE0)/* reproduces itself from source. cc not invoked."

.PHONY: all cstage wwstage test install clean bootstrap nocc bootstrap-snapshot