# =============================================================================

# forApollo — Fortran Compilation Makefile (Stage 1 of two-stage build)

# Copyright The Fantastic Planet — By David Clabaugh

#

# This Makefile compiles Fortran kernels to a static archive.

# Stage 2 (Zig safety layer + C ABI exports) is handled by build.zig.

#

# Usage:

# make # compile all Fortran sources → libforapollo_fortran.a

# make lib # same as all

# make test # compile and run Fortran unit tests

# make prebuilt # copy archive to prebuilt/<platform>/

# make clean # remove build/ artifacts

#

# Cross-compilation:

# make MARCH=armv8-a # override -march for Jetson / RPi

# =============================================================================

# --- Configurable flags -------------------------------------------------------

FC ?= gfortran

MARCH ?= native

FFLAGS := -O3 -ftree-vectorize -fPIC -cpp -std=f2008 -fall-intrinsics \

-Wall -Wextra -Wimplicit-interface -fopenmp -march=$(MARCH)

# --- Directories --------------------------------------------------------------

SRC_DIR := src/fortran

BUILD_DIR := build

OBJ_DIR := $(BUILD_DIR)/obj

TEST_DIR := tests/fortran

# --- Platform detection for prebuilt target -----------------------------------

#

# Darwin (macOS) with Apple Silicon → macos-arm64

# Linux aarch64 (Jetson, RPi) → linux-arm64

# Linux x86_64 (cloud, CI) → linux-x86_64

#

UNAME_S := $(shell uname -s)

UNAME_M := $(shell uname -m)

ifeq ($(UNAME_S),Darwin)

PLATFORM := macos-arm64

else ifeq ($(UNAME_M),x86_64)

PLATFORM := linux-x86_64

else

PLATFORM := linux-arm64

endif

PREBUILT_DIR := prebuilt/$(PLATFORM)

# --- Output archive -----------------------------------------------------------

#

# Archive goes into build/{platform}/lib/ to match Zig build.zig resolution.

#

PLAT_LIB_DIR := $(BUILD_DIR)/$(PLATFORM)/lib

LIB := $(PLAT_LIB_DIR)/libforapollo_fortran.a

# --- Source compilation order -------------------------------------------------

#

# Module dependency order (must compile lower layers before upper layers):

#

# Layer 0 — Models (no intra-Apollo deps): dynamics, observe

# Layer 1 — Engine core: estimate, propagate

# Layer 2 — Engine aux: guidance, coords

# Layer 3 — Domain utilities: astro, environ, time

#

SRCS := \

$(SRC_DIR)/forapollo_dynamics.f90 \

$(SRC_DIR)/forapollo_observe.f90 \

$(SRC_DIR)/forapollo_estimate.f90 \

$(SRC_DIR)/forapollo_propagate.f90 \

$(SRC_DIR)/forapollo_guidance.f90 \

$(SRC_DIR)/forapollo_coords.f90 \

$(SRC_DIR)/forapollo_astro.f90 \

$(SRC_DIR)/forapollo_environ.f90 \

$(SRC_DIR)/forapollo_time.f90

# Derive object file names: src/fortran/forapollo_X.f90 → build/obj/forapollo_X.o

OBJS := $(patsubst $(SRC_DIR)/%.f90,$(OBJ_DIR)/%.o,$(SRCS))

# --- Test sources (tests/fortran/test_*.f90) ----------------------------------

TEST_SRCS := $(wildcard $(TEST_DIR)/test_*.f90)

TEST_BINS := $(patsubst $(TEST_DIR)/%.f90,$(BUILD_DIR)/%,$(TEST_SRCS))

# =============================================================================

# Targets

# =============================================================================

.PHONY: all lib prebuilt clean test

# Default target

all: lib

# --- lib: compile Fortran kernels → static archive ---------------------------

lib: $(LIB)

$(LIB): $(OBJS) | $(PLAT_LIB_DIR)

@echo "[AR] $@"

ar rcs $@ $^

$(PLAT_LIB_DIR):

mkdir -p $(PLAT_LIB_DIR)

# Pattern rule: compile each .f90 → .o

# Modules (.mod) are emitted into OBJ_DIR so they are found by dependent units.

$(OBJ_DIR)/%.o: $(SRC_DIR)/%.f90 | $(OBJ_DIR)

@echo "[FC] $<"

$(FC) $(FFLAGS) -J$(OBJ_DIR) -I$(OBJ_DIR) -c $< -o $@

# Ensure build directories exist

$(OBJ_DIR):

mkdir -p $(OBJ_DIR)

$(BUILD_DIR):

mkdir -p $(BUILD_DIR)

# --- prebuilt: copy archive to prebuilt/<platform>/ --------------------------

#

# Called when generating a new committed prebuilt snapshot.

# Destination directory must already exist (created as part of repo layout).

prebuilt: $(LIB)

@echo "[PREBUILT] copying to $(PREBUILT_DIR)/lib/"

@mkdir -p $(PREBUILT_DIR)/lib

cp $(LIB) $(PREBUILT_DIR)/lib/libforapollo_fortran.a

@echo "[PREBUILT] done — $(PREBUILT_DIR)/lib/libforapollo_fortran.a"

# --- test: compile and run Fortran unit tests --------------------------------

#

# Each tests/fortran/test_*.f90 is compiled into its own executable and linked

# against the objects (not the archive, so there is no separate lib dep).

# Tests are run in sequence; any non-zero exit fails the target.

test: $(OBJS) $(TEST_BINS)

@echo "[TEST] running $(words $(TEST_BINS)) test(s)"

@failed=0; \

for t in $(TEST_BINS); do \

echo "[RUN] $$t"; \

$$t; \

if [ $$? -ne 0 ]; then \

echo "[FAIL] $$t"; \

failed=$$((failed + 1)); \

else \

echo "[PASS] $$t"; \

fi; \

done; \

if [ $$failed -ne 0 ]; then \

echo "[TEST] $$failed test(s) failed"; \

exit 1; \

else \

echo "[TEST] all tests passed"; \

fi

# Pattern rule: compile test binary

# Links against the object files so module .mod files are available.

$(BUILD_DIR)/%: $(TEST_DIR)/%.f90 $(OBJS) | $(BUILD_DIR)

@echo "[FC-TEST] $<"

$(FC) $(FFLAGS) -J$(OBJ_DIR) -I$(OBJ_DIR) $< $(OBJS) -o $@

# --- clean: remove all build artifacts ----------------------------------------

clean:

@echo "[CLEAN] removing $(BUILD_DIR)/"

rm -rf $(BUILD_DIR)