Change exe name to follow the module of the main. Detect missing / multiple main functions.

README.md

@@ -234,7 +234,9 @@ Then run
 c3c compile main.c3
 ```
 
-The generated binary will be called `a.out`.
+The generated binary will by default be named after the module that contains the main
+function. In our case that is `hello_world`, so the resulting binary will be
+called `hello_world` or `hello_world.exe`depending on platform.
 
 ### Compiling
 

src/compiler/compiler.c

@@ -123,21 +123,36 @@ void thread_compile_task_tb(void *compile_data)
 }
 
 
-static const char *active_target_name(void)
+static const char *exe_name(void)
 {
+	assert(global_context.main);
+	const char *name;
+	if (active_target.name)
+	{
+		name = active_target.name;
+	}
+	else
+	{
+		Path *path = global_context.main->unit->module->name;
+		size_t first = 0;
+		for (size_t i = path->len; i > 0; i--)
+		{
+			if (path->module[i - 1] == ':')
+			{
+				first = i;
+				break;
+			}
+		}
+		name = &path->module[first];
+	}
 	switch (active_target.arch_os_target)
 	{
 		case WINDOWS_X86:
 		case WINDOWS_X64:
 		case MINGW_X64:
-			if (active_target.name)
-			{
-				return str_cat(active_target.name, ".exe");
-			}
-			return "a.exe";
+			return str_cat(name, ".exe");
 		default:
-			if (active_target.name) return active_target.name;
-			return "a.out";
+			return name;
 	}
 }
 
@@ -268,12 +283,21 @@ void compiler_compile(void)
 	}
 	compiler_ir_gen_time = bench_mark();
 
+	const char *output_exe = NULL;
+	if (!active_target.no_link && !active_target.test_output && (active_target.type == TARGET_TYPE_EXECUTABLE || active_target.type == TARGET_TYPE_TEST))
+	{
+		if (!global_context.main)
+		{
+			puts("No main function was found, compilation only object files are generated.");
+		}
+		else
+		{
+			output_exe = exe_name();
+		}
+	}
 
 	free_arenas();
 
-
-	bool create_exe = !active_target.no_link && !active_target.test_output && (active_target.type == TARGET_TYPE_EXECUTABLE || active_target.type == TARGET_TYPE_TEST);
-
 	uint32_t output_file_count = vec_size(gen_contexts);
 	unsigned cfiles = vec_size(active_target.csources);
 
@@ -322,26 +346,27 @@ void compiler_compile(void)
 	for (unsigned i = 0; i < output_file_count; i++)
 	{
 		obj_files[i] = compile_data[i].object_name;
-		assert(obj_files[i] || !create_exe);
+		assert(obj_files[i] || !output_exe);
 	}
 
+
+
 	output_file_count += cfiles;
 	free(compile_data);
 	compiler_codegen_time = bench_mark();
 
-	if (create_exe)
+	if (output_exe)
 	{
-		const char *output_name = active_target_name();
 		if (platform_target.os != OS_TYPE_WIN32 && active_target.arch_os_target == default_target && !active_target.force_linker)
 		{
-			platform_linker(output_name, obj_files, output_file_count);
+			platform_linker(output_exe, obj_files, output_file_count);
 			compiler_link_time = bench_mark();
 			compiler_print_bench();
 		}
 		else
 		{
 			compiler_print_bench();
-			if (!obj_format_linking_supported(platform_target.object_format) || !linker(output_name, obj_files,
+			if (!obj_format_linking_supported(platform_target.object_format) || !linker(output_exe, obj_files,
 			                                                                            output_file_count))
 			{
 				printf("No linking is performed due to missing linker support.\n");
@@ -352,8 +377,8 @@ void compiler_compile(void)
 		if (active_target.run_after_compile)
 		{
 			DEBUG_LOG("Will run");
-			printf("Launching %s...\n", output_name);
-			int ret = system(platform_target.os == OS_TYPE_WIN32 ? output_name : str_printf("./%s", output_name));
+			printf("Launching %s...\n", output_exe);
+			int ret = system(platform_target.os == OS_TYPE_WIN32 ? output_exe : str_printf("./%s", output_exe));
 			printf("Program finished with exit code %d.", ret);
 		}
 	}
@@ -536,6 +561,7 @@ void compile()
 		active_target.csources = target_expand_source_names(active_target.csource_dirs, c_suffix_list, 1, false);
 	}
 	global_context.sources = active_target.sources;
+	global_context.main = NULL;
 	target_setup(&active_target);
 	resolve_libraries();
 

src/compiler/compiler_internal.h

@@ -1491,6 +1491,7 @@ typedef struct
 	DeclTable generic_symbols;
 	Path std_module_path;
 	Decl *panic_fn;
+	Decl *main;
 } GlobalContext;
 
 

src/compiler/sema_decls.c

@@ -1796,6 +1796,15 @@ static inline bool sema_analyse_main_function(SemaContext *context, Decl *decl)
 	assert(body);
 	function->func_decl.body = astid(body);
 	context->unit->main_function = function;
+	if (global_context.main)
+	{
+		SEMA_ERROR(function, "Duplicate main functions found.");
+		SEMA_PREV(global_context.main, "The first one was found here.");
+	}
+	else
+	{
+		global_context.main = function;
+	}
 	return true;
 }
 

src/version.h

@@ -1 +1 @@
-#define COMPILER_VERSION "0.3.5"
+#define COMPILER_VERSION "0.3.6"