projgen: Working!

The test-gmod project now builds without any hand-written Makefile, building it by using projgen to generate a makefile then make to build it now works!

I'm pretty happy with it, there's a couple things I might want to fix/add, but for now it's functionally ready.

Now I can probably focus on building a Containerfile for the build image.

.gitignore

@@ -4,3 +4,9 @@ module_build/
 
 .cache/
 .vscode/
+
+# generated products of the GMOD test program
+test-gmod/Makefile
+test-gmod/obj
+test-gmod/*.elf
+test-gmod/*.bin

ideas.md

@@ -11,7 +11,7 @@ This is basically the working ideas for the LCPU project.
 
 ## Code upload
 
-- Upload a raw binary to execute, generated from any user tooling (goes into server `data/lcpu/users/[steamid]/`)
+- Upload a raw binary to execute, generated from any user tooling (goes into the server `data/lcpu/users/[steamid]/`)
 	- Yes, this means you can run Linux in GMod. No, I'm not sorry.
 
 ## Integrated simple project workflow (WIP, not in the addon yet)
@@ -23,21 +23,18 @@ This is basically the working ideas for the LCPU project.
 	- At the root of a project, a `project.json` file is expected to exist, with contents like:
 	```json
 	{
-		"Project": {
 		"Name": "test",
 
-			// Define all build configurations here
 		"Configurations": {
 			"Debug": {
-					"CCompileFlags": "-O0 ${BaseCCompileFlags}",
+				"CCompileFlags": "-O0",
-					"CppCompileFlags": "-O0 ${BaseCppCompileFlags}"
+				"CppCompileFlags": "-O0",
+				"LinkerFlags": ""
 			},
 			"Release": {
-					"CCompileFlags": "-O2 ${BaseCCompileFlags}",
+				"CCompileFlags": "-O2",
-					"CppCompileFlags": "-O2 ${BaseCppCompileFlags}",
+				"CppCompileFlags": "-O2",
-					// If a variable is unset it will usually default to
+				"LinkerFlags": "-Wl,--gc-sections"
-					// ${Base${VariableName}}
-					"LinkerFlags": "-Wl,--gc-sections ${BaseLinkerFlags}"
 			}
 		},
 
@@ -47,32 +44,26 @@ This is basically the working ideas for the LCPU project.
 			"main.c"
 		]
 	}
-	}
 	```
-
+	- This will be transpiled into a `Makefile` when built.
-	- `BaseCCompileFlags` and `BaseCppCompileFlags` are defaulted to sane values for each language.
-
-	- This will be transpiled into a `Makefile` by the addon.
 		- A standalone tool will be provided and used for transpiling `project.json` to a `Makefile` (and maybe even built into the container and transpiled there, to reduce the actions on the host to just the podman run?)
-		- which, when a Build is done in GMod; is then run with `make` in a temporary podman container which only has access to the source code folder for the project (and nothing else, besides riscv tools which are in the image).
+		- which, when a Build is requested in GMod; is then run with `make` in a temporary podman container which only has access to the source code folder for the project (and nothing else, besides riscv tools which are in the image).
-			- Command line is probably something like `make CONFIG=${config}`
+			- Command line is probably something like `podman run localhost/lcpu-build:latest -v /project:[host project dir] make CONFIG=${config}`
-		- the output binary will be stored alongside the source code on the server side, with a name like `${name}-${config}.bin`
+		- the output binary will be stored alongside the source code on the server side, with a name like `${name}_${config}.bin`
 			- This file can then be selected for loading (without needing to be uploaded from the client).
 
 
 - There is no conditional compilation in the `project.json` system
-	- All files in a project are always built by that project.
 
 - No notion of subprojects/build dependencies
-	- This is meant to be simple for easy development in GMod. If you want complex build features you can export the project onto your own computer and use `lcpu_projgen` to generate Makefiles (which you can then maintain)
 
-- Text editor used to edit project source files
+- Text editor used to edit project source files in GMod
 	- Use the Wire editor? (we need wiremod anyways, and the text editor is.. OK I suppose.)
 		- Or: https://github.com/Metastruct/gmod-monaco
 			- https://github.com/JustMrPhoenix/Noir/tree/master
 
 - Some example projects?
-	- A simple bare metal "Hello World"
+	- A simple bare metal "Hello World" using the SDK headers
 	- I joke about it, but an RTOS would be really nice and a good stress test of the project system (for usage in "real" projects.)
 
 ## Moderation/administration tools

native/projects/projgen/src/BaseConfig.hpp

@@ -1,8 +1,11 @@
+//! These are the hardcoded defaults projgen uses for configuring Makefiles.
+//! Only change these if you know what they do.
 #pragma once 
 
-/// These are the hardcoded defaults
 #define PROJGEN_CC "riscv32-unknown-elf-gcc"
 #define PROJGEN_CXX "riscv32-unknown-elf-g++"
+#define PROJGEN_LD "riscv32-unknown-elf-gcc"
+#define PROJGEN_OBJCOPY "riscv32-unknown-elf-objcopy"
 #define PROJGEN_BASE_C_FLAGS "-ffreestanding -fno-stack-protector -fdata-sections -ffunction-sections -march=rv32ima -mabi=ilp32"
-#define PROJGEN_BASE_CC_FLAGS "-ffreestanding -fno-stack-protector -fdata-sections -ffunction-sections -march=rv32ima -mabi=ilp32"
+#define PROJGEN_BASE_CC_FLAGS "-ffreestanding -fno-rtti -fno-exceptions -fno-stack-protector -fdata-sections -ffunction-sections -march=rv32ima -mabi=ilp32"
 #define PROJGEN_BASE_LD_FLAGS "-nostdlib"

native/projects/projgen/src/FsUtils.hpp

@@ -1,3 +1,7 @@
+#pragma once
+
+#include <daw/json/daw_json_link.h>
+
 #include <cstdio>
 #include <filesystem>
 #include <memory>
@@ -7,13 +11,13 @@ namespace fs = std::filesystem;
 
 namespace projgen::util {
 
-	using unique_file_ptr = std::unique_ptr<std::FILE, decltype(&std::fclose)>;
+	using UniqueFilePtr = std::unique_ptr<std::FILE, decltype(&std::fclose)>;
 
-	unique_file_ptr UniqueFopen(std::string_view path, std::string_view mode) {
+	inline UniqueFilePtr UniqueFopen(std::string_view path, std::string_view mode) {
-		return unique_file_ptr(std::fopen(path.data(), mode.data()), &std::fclose);
+		return UniqueFilePtr(std::fopen(path.data(), mode.data()), &std::fclose);
 	}
 
-	std::string ReadFileAsString(const fs::path& path) {
+	inline std::string ReadFileAsString(const fs::path& path) {
 		auto file = UniqueFopen(path.string(), "r");
 		std::string data;
 		if(file) {
@@ -27,4 +31,10 @@ namespace projgen::util {
 		return data;
 	}
 
+	template <class T>
+	inline T ParseJsonFromFile(const fs::path& path) {
+		auto data = projgen::util::ReadFileAsString(path);
+		return daw::json::from_json<T>(data);
+	}
+
 } // namespace projgen::util

native/projects/projgen/src/Makefile.hpp

@@ -0,0 +1,181 @@
+#pragma once
+
+#include <format>
+#include <lucore/Assert.hpp>
+#include <string>
+#include <unordered_map>
+
+#include "BaseConfig.hpp"
+#include "FsUtils.hpp"
+#include "Project.hpp"
+
+namespace projgen::make {
+
+	// base class for makefile rules
+	struct MakefileGeneratable {
+		virtual ~MakefileGeneratable() = default;
+		virtual std::string Generate() = 0;
+	};
+
+	struct MakefileGlobalVariables : public MakefileGeneratable {
+		std::unordered_map<std::string, std::string> values;
+
+		// initalize for the global collection
+		MakefileGlobalVariables(const std::string& projectName, const std::string& objects) {
+			values["NAME"] = projectName;
+			values["CC"] = PROJGEN_CC;
+			values["CXX"] = PROJGEN_CXX;
+			values["LD"] = PROJGEN_LD;
+			values["OBJCOPY"] = PROJGEN_OBJCOPY;
+
+			values["BASE_CCFLAGS"] = PROJGEN_BASE_C_FLAGS;
+			values["BASE_CXXFLAGS"] = PROJGEN_BASE_CC_FLAGS;
+			values["BASE_LDFLAGS"] = PROJGEN_BASE_LD_FLAGS;
+
+			values["OBJS"] = objects;
+		}
+
+		std::string Generate() override {
+			auto str = std::string();
+			for(auto& kv : values) {
+				str += std::format("{} = {}\n", kv.first, kv.second);
+			}
+
+			return str;
+		}
+	};
+
+	struct MakefileConfiguration : public MakefileGeneratable {
+		MakefileConfiguration(const std::unordered_map<std::string, projgen::Project::Configuration>& configs) : configs(configs) {}
+
+		std::string Generate() override {
+			auto string = std::string();
+
+			for(auto& config : configs) {
+				string += std::format("ifeq ($(CONFIG),{})\n", config.first);
+				string += std::format("{}_Valid = yes\n", config.first);
+				string += std::format("{}_CCFLAGS = $(BASE_CCFLAGS) {}\n", config.first, config.second.cCompileFlags);
+				string += std::format("{}_CXXFLAGS = $(BASE_CXXFLAGS) {}\n", config.first, config.second.cppCompileFlags);
+				string += std::format("{}_LDFLAGS = $(BASE_LDFLAGS) {}\n", config.first, config.second.linkerFlags.value_or(""));
+				string += std::format("endif\n");
+			}
+
+			string += std::format("ifeq ($(CONFIG),)\n$(error Please specify a build configuration)\nendif\n");
+			string += std::format("ifneq ($($(CONFIG)_Valid), yes)\n$(error Invalid configuration $(CONFIG))\nendif\n");
+			return string;
+		}
+
+	   private:
+		const std::unordered_map<std::string, projgen::Project::Configuration>& configs;
+	};
+
+	// a general product rule
+	struct MakefileProductRule : public MakefileGeneratable {
+		std::string product;
+		std::string consumeDeps;
+
+		MakefileProductRule(const std::string& product, const std::string& consumeDeps) : product(product), consumeDeps(consumeDeps) {}
+
+		std::string Generate() override { return std::format("{}: {}\n\t{}", product, consumeDeps, GenerateRuleCommand()); }
+
+	   private:
+		virtual std::string GenerateRuleCommand() = 0;
+	};
+
+	struct MakefileAllRule : MakefileGeneratable {
+		std::string product;
+		std::string consumeDeps;
+
+		MakefileAllRule() : product("all"), consumeDeps("obj/$(CONFIG)/ $(NAME)_$(CONFIG).bin") {}
+
+		std::string Generate() override { return std::format("{}: {}\n", product, consumeDeps); }
+	};
+
+	struct MakefileCleanRule : MakefileProductRule {
+		MakefileCleanRule() : MakefileProductRule("clean", "") {}
+
+	   private:
+		std::string GenerateRuleCommand() override { return "rm -rf $(NAME)_$(CONFIG).elf $(NAME)_$(CONFIG).bin obj/$(CONFIG)"; }
+	};
+
+	struct MakefileObjDirRule : MakefileProductRule {
+		MakefileObjDirRule() : MakefileProductRule("obj/$(CONFIG)/", "") {}
+
+	   private:
+		std::string GenerateRuleCommand() override { return "mkdir -p $@"; }
+	};
+
+	// a pattern rule
+	// e.g "%.o: %.c" or such
+	struct MakefilePatternRule : public MakefileGeneratable {
+		std::string productExtension;
+		std::string consumeExtension;
+
+		MakefilePatternRule(const std::string& productExtension, const std::string& consumeExtension)
+			: productExtension(productExtension), consumeExtension(consumeExtension) {}
+
+		std::string Generate() override { return std::format("{}: {}\n\t{}", productExtension, consumeExtension, GenerateRuleCommand()); }
+
+	   private:
+		virtual std::string GenerateRuleCommand() = 0;
+	};
+
+	struct MakefileAsmRule : public MakefilePatternRule {
+		MakefileAsmRule() : MakefilePatternRule("obj/$(CONFIG)/%.o", "%.S") {}
+
+	   private:
+		std::string GenerateRuleCommand() override { return "$(CC) -xassembler-with-cpp -c $($(CONFIG)_CCFLAGS) $< -o $@"; }
+	};
+
+	struct MakefileCRule : public MakefilePatternRule {
+		MakefileCRule() : MakefilePatternRule("obj/$(CONFIG)/%.o", "%.c") {}
+
+	   private:
+		std::string GenerateRuleCommand() override { return "$(CC) -c $($(CONFIG)_CCFLAGS) $< -o $@"; }
+	};
+
+	struct MakefileCXXRule : public MakefilePatternRule {
+		MakefileCXXRule() : MakefilePatternRule("obj/$(CONFIG)/%.o", "%.cpp") {}
+
+	   private:
+		std::string GenerateRuleCommand() override { return "$(CXX) -c $($(CONFIG)_CXXFLAGS) $< -o $@"; }
+	};
+
+	struct MakefileLinkRule : public MakefileProductRule {
+		MakefileLinkRule() : MakefileProductRule("$(NAME)_$(CONFIG).elf", "$(OBJS)") {};
+
+	   private:
+		std::string GenerateRuleCommand() override { return "$(LD) $($(CONFIG)_LDFLAGS) $(OBJS) -o $@"; }
+	};
+
+	struct MakefileFlatBinaryRule : MakefileProductRule {
+		MakefileFlatBinaryRule() : MakefileProductRule("$(NAME)_$(CONFIG).bin", "$(NAME)_$(CONFIG).elf") {};
+
+	   private:
+		std::string GenerateRuleCommand() override { return "$(OBJCOPY) $^ -O binary $@"; }
+	};
+
+	struct MakefileWriter {
+		MakefileWriter(const fs::path& path) {
+			file = projgen::util::UniqueFopen((path / "Makefile").string(), "w");
+			LUCORE_CHECK(file, "Could not open {} for writing", (path / "Makefile").string());
+		}
+
+		bool Write(const std::vector<std::unique_ptr<MakefileGeneratable>>& g) {
+			for(auto& p : g) {
+				auto generated_data = p->Generate();
+				if(std::fwrite(generated_data.data(), 1, generated_data.length(), file.get()) != generated_data.length())
+					return false;
+
+				if(!fputc('\n', file.get()))
+					return false;
+			}
+
+			return true;
+		}
+
+	   private:
+		projgen::util::UniqueFilePtr file { nullptr, std::fclose };
+	};
+
+} // namespace projgen::make

native/projects/projgen/src/Project.hpp

@@ -1,10 +1,12 @@
-#include <daw/json/daw_json_link.h>
+#pragma once
 
 #include <optional>
 #include <string>
 #include <unordered_map>
 #include <vector>
 
+#include "FsUtils.hpp"
+
 namespace projgen {
 	struct Project {
 		struct Configuration {
@@ -20,6 +22,52 @@ namespace projgen {
 		std::vector<std::string> sourceFileNames;
 	};
 
+	// this describes a source file
+	struct SourceFile {
+		enum class Type {
+			Invalid,	   // invalid file
+			AsmSourceFile, // Assembly source file
+			CSourceFile,   // C source code
+			CppSourceFile, // C++ source code
+			LinkerScript,  // prepended to linker flags with a -T (only one can exist in a project)
+		};
+
+		static constexpr Type TypeFromExtension(std::string_view extension) {
+			if(extension == ".S")
+				return Type::AsmSourceFile;
+			else if(extension == ".c")
+				return Type::CSourceFile;
+			else if(extension == ".cpp")
+				return Type::CppSourceFile;
+			else if(extension == ".ld")
+				return Type::LinkerScript;
+			else
+				return Type::Invalid;
+		}
+
+		explicit SourceFile(const fs::path& path) {
+			if(path.has_extension())
+				type = TypeFromExtension(path.extension().string());
+			else
+				type = Type::Invalid;
+
+			this->path = path.filename();
+		}
+
+		static std::vector<SourceFile> MakeArray(const fs::path& sourcePath, const std::vector<std::string>& filenames) {
+			auto vec = std::vector<SourceFile>();
+			vec.reserve(filenames.size());
+
+			for(auto& filename : filenames)
+				vec.emplace_back((sourcePath / filename));
+
+			return vec;
+		}
+
+		Type type;
+		fs::path path;
+	};
+
 } // namespace projgen
 
 /// DAW JSON Link bindings
@@ -36,8 +84,8 @@ namespace daw::json {
 
 	template <>
 	struct json_data_contract<projgen::Project> {
-		using type =
+		using type = json_member_list<
-		json_member_list<json_string<"Name">,
+		json_string<"Name">,
 		json_key_value<"Configurations", std::unordered_map<std::string, projgen::Project::Configuration>, projgen::Project::Configuration>,
 		json_array<"Sources", std::string> >;
 

native/projects/projgen/src/main.cpp

@@ -1,89 +1,87 @@
 //! Main for the LCPU project generator
 
+#include <filesystem>
+#include <lucore/Assert.hpp>
 #include <lucore/Logger.hpp>
 #include <lucore/StdoutSink.hpp>
 #include <unordered_map>
 
 #include "BaseConfig.hpp"
 #include "FsUtils.hpp"
+#include "Makefile.hpp"
 #include "Project.hpp"
 
-template <class T>
+// TODO:
-T ParseJsonFromFile(const fs::path& path) {
+// Once there's better C++23 ranges support, this can/should be replaced with:
-	auto data = projgen::util::ReadFileAsString(path);
+// (objects | views::join_with(' ')
-	return daw::json::from_json<T>(data);
+//          | std::ranges::to<std::string>())
+// I want better ranges support in gcc and clang, this already works in MSVC :(
+inline auto join(const std::vector<std::string>& values, const std::string_view seperator = " ") {
+	auto string = std::string {};
+	for(auto& value : values)
+		string += std::format("{}{}", value, seperator);
+	return string;
 }
 
-// this describes a source file
-struct SourceFile {
-	enum class Type {
-		Invalid,	   // invalid file
-		AsmSourceFile, // Assembly source file
-		CSourceFile,   // C source code
-		CppSourceFile, // C++ source code
-		LinkerScript,  // prepended to linker flags with a -T (only one can exist in a project)
-	};
-
-	static constexpr Type TypeFromExtension(std::string_view extension) {
-		if(extension == "s" || extension == "S")
-			return Type::AsmSourceFile;
-
-		if(extension == "c")
-			return Type::CSourceFile;
-		if(extension == "cpp" || extension == "cc")
-			return Type::CppSourceFile;
-		if(extension == "ld")
-			return Type::LinkerScript;
-
-		return Type::Invalid;
-	}
-
-	explicit SourceFile(const std::string& filename) : filename(filename) {
-		if(auto pos = filename.rfind('.'); pos != std::string::npos) {
-			type = TypeFromExtension(filename.substr(pos + 1));
-		} else {
-			type = Type::Invalid;
-		}
-	}
-
-	static std::vector<SourceFile> MakeArray(const std::vector<std::string>& filenames) {
-		auto vec = std::vector<SourceFile>();
-		vec.reserve(filenames.size());
-
-		for(auto& filename : filenames)
-			vec.emplace_back(filename);
-
-		return vec;
-	}
-
-	Type type;
-	std::string filename;
-};
-
 int main(int argc, char** argv) {
 	lucore::LoggerAttachStdout();
-
+	lucore::LogInfo("LCPU project generator");
-	lucore::LogInfo("LCPU project generator!");
 
 	auto project_json_path = (fs::current_path() / "project.json");
 
 	if(!fs::exists(project_json_path)) {
-		lucore::LogFatal("The directory \"{}\" does not seem like it's a project to me", fs::current_path().string());
+		lucore::LogFatal("The directory \"{}\" does not seem like it's a LCPU project to me", fs::current_path().string());
 		return 1;
 	}
 
 	try {
-		auto project = ParseJsonFromFile<projgen::Project>(project_json_path);
+		auto project = projgen::util::ParseJsonFromFile<projgen::Project>(project_json_path);
 
-		for(auto& pair : project.configurations) {
+		lucore::LogInfo("Generating Makefile for project \"{}\".", project.name);
-			std::printf("%s: %s %s %s\n", pair.first.c_str(), pair.second.cCompileFlags.c_str(), pair.second.cppCompileFlags.c_str(),
-						pair.second.linkerFlags.value_or(PROJGEN_BASE_LD_FLAGS).c_str());
-		}
 
-		auto sourceFiles = SourceFile::MakeArray(project.sourceFileNames);
+		auto sourceFiles = projgen::SourceFile::MakeArray(fs::current_path(), project.sourceFileNames);
+		auto objects = std::vector<std::string> {};
+		bool foundLdScript = false;
 
 		for(auto& source : sourceFiles) {
-			std::printf("%s -> %d\n", source.filename.c_str(), source.type);
+			LUCORE_CHECK(source.type != projgen::SourceFile::Type::Invalid,
+						 "Source file {} with Invalid type in source files. Refusing to generate project", source.path.string());
+
+			if(source.type == projgen::SourceFile::Type::LinkerScript) {
+				LUCORE_CHECK(!foundLdScript, "Project invalid; has more than 1 .ld script file");
+				foundLdScript = true;
+				for(auto& kv : project.configurations) {
+					if(kv.second.linkerFlags.has_value()) {
+						kv.second.linkerFlags = std::format("-T {} {}", source.path.string(), *kv.second.linkerFlags);
+					} else {
+						kv.second.linkerFlags = std::format("-T {}", source.path.string());
+					}
+				}
+				continue;
+			}
+
+			objects.push_back(std::format("obj/$(CONFIG)/{}", source.path.replace_extension(".o").string()));
+		}
+
+		projgen::make::MakefileWriter writer(fs::current_path());
+
+		auto generators = std::vector<std::unique_ptr<projgen::make::MakefileGeneratable>> {};
+		generators.emplace_back(new projgen::make::MakefileGlobalVariables(project.name, join(objects)));
+		generators.emplace_back(new projgen::make::MakefileConfiguration(project.configurations));
+		generators.emplace_back(new projgen::make::MakefileAllRule());
+		generators.emplace_back(new projgen::make::MakefileCleanRule());
+		generators.emplace_back(new projgen::make::MakefileObjDirRule());
+		generators.emplace_back(new projgen::make::MakefileAsmRule());
+		generators.emplace_back(new projgen::make::MakefileCRule());
+		generators.emplace_back(new projgen::make::MakefileCXXRule());
+		generators.emplace_back(new projgen::make::MakefileFlatBinaryRule());
+		generators.emplace_back(new projgen::make::MakefileLinkRule());
+
+		if(!writer.Write(generators)) {
+			lucore::LogError("Could not generate project");
+			return 1;
+		} else {
+			lucore::LogInfo("Generated Makefile \"{}\".", (fs::current_path() / "Makefile").string());
 		}
 
 	} catch(daw::json::json_exception& ex) {

test-gmod/Makefile.Hand

@@ -1,53 +0,0 @@
-PROJECT = test
-
-# where your rv32 toolchain is
-TCPATH = /home/lily/bin/riscv/bin
-PREFIX = $(TCPATH)/riscv32-unknown-elf
-
-CC = $(PREFIX)-gcc
-CXX = $(PREFIX)-g++
-
-ARCHFLAGS = -ffreestanding -fno-stack-protector -fdata-sections -ffunction-sections -march=rv32ima -mabi=ilp32 
-CCFLAGS = -g -Os $(ARCHFLAGS) -std=c18
-CXXFLAGS = $(ARCHFLAGS) -g -Os -std=c++20 -fno-exceptions -fno-rtti
-LDFLAGS = -T binary.ld -nostdlib -Wl,--gc-sections
-
-OBJS = start.o \
-	main.o
-
-.PHONY: all test clean
-
-all: $(PROJECT).bin $(PROJECT).debug.txt
-
-# this assumes the lcpu project build dir you're using is 
-# [lcpu repo root]/build
-test: $(PROJECT).bin $(PROJECT).debug.txt
-	../../../../build/projects/riscv_test_harness/rvtest $<
-
-clean:
-	rm $(PROJECT).elf $(PROJECT).bin $(PROJECT).debug.txt $(OBJS)
-
-# Link rules
-
-$(PROJECT).elf: $(OBJS)
-	$(CC) $(CCFLAGS) $(LDFLAGS) -o $@ $(OBJS) 
-
-$(PROJECT).bin : $(PROJECT).elf
-	$(PREFIX)-objcopy $^ -O binary $@
-
-$(PROJECT).debug.txt : $(PROJECT).elf
-	$(PREFIX)-objdump -t $^ > $@
-	$(PREFIX)-objdump -S $^ >> $@
-
-# Compile rules
-
-%.o: %.cpp
-	$(CXX) -c $(CXXFLAGS) $< -o $@
-
-%.o: %.c
-	$(CC) -c $(CCFLAGS) $< -o $@
-
-%.o: %.S
-	$(CC) -x assembler-with-cpp -march=rv32ima -mabi=ilp32 -c $< -o $@
-
-