checker: stricter []&Type{len:x} check

vlib/os/os.c.v

@@ -949,6 +949,7 @@ pub fn open_append(path string) ?File {
 // Note: this function will NOT return when successfull, since
 // the child process will take control over execution.
 pub fn execvp(cmdpath string, cmdargs []string) ? {
+	unsafe {
 		mut cargs := []&char{}
 		cargs << &char(cmdpath.str)
 		for i in 0 .. cmdargs.len {
@@ -964,9 +965,11 @@ pub fn execvp(cmdpath string, cmdargs []string) ? {
 		if res == -1 {
 			return error_with_code(posix_get_error_msg(C.errno), C.errno)
 		}
+
 		// just in case C._execvp returned ... that happens on windows ...
 		exit(res)
 	}
+}
 
 // execve - loads and executes a new child process, *in place* of the current process.
 // The child process executable is located in `cmdpath`.
@@ -975,6 +978,7 @@ pub fn execvp(cmdpath string, cmdargs []string) ? {
 // Note: this function will NOT return when successfull, since
 // the child process will take control over execution.
 pub fn execve(cmdpath string, cmdargs []string, envs []string) ? {
+	unsafe {
 		mut cargv := []&char{}
 		mut cenvs := []&char{}
 		cargv << &char(cmdpath.str)
@@ -998,6 +1002,7 @@ pub fn execve(cmdpath string, cmdargs []string, envs []string) ? {
 			return error_with_code(posix_get_error_msg(C.errno), C.errno)
 		}
 	}
+}
 
 // is_atty returns 1 if the `fd` file descriptor is open and refers to a terminal
 pub fn is_atty(fd int) int {

vlib/sync/pool/pool.v

@@ -81,6 +81,7 @@ pub fn (mut pool PoolProcessor) work_on_pointers(items []voidptr) {
 	if pool.njobs > 0 {
 		njobs = pool.njobs
 	}
+	unsafe {
 		pool.thread_contexts = []voidptr{len: items.len}
 		pool.results = []voidptr{len: items.len}
 		pool.items = []voidptr{cap: items.len}
@@ -94,6 +95,7 @@ pub fn (mut pool PoolProcessor) work_on_pointers(items []voidptr) {
 				process_in_thread(mut pool, i)
 			}
 		}
+	}
 	pool.waitgroup.wait()
 }
 
@@ -136,12 +138,14 @@ pub fn (pool &PoolProcessor) get_results<T>() []T {
 
 // get_results_ref - get a list of type safe results in the main thread.
 pub fn (pool &PoolProcessor) get_results_ref<T>() []&T {
+	unsafe {
 		mut res := []&T{cap: pool.results.len}
 		for i in 0 .. pool.results.len {
 			res << &T(pool.results[i])
 		}
 		return res
 	}
+}
 
 // set_shared_context - can be called during the setup so that you can
 // provide a context that is shared between all worker threads, like

vlib/v/builder/builder.v

@@ -251,6 +251,7 @@ pub fn (mut b Builder) resolve_deps() {
 		eprintln(mods.str())
 		eprintln('-------------------------------')
 	}
+	unsafe {
 		mut reordered_parsed_files := []&ast.File{}
 		for m in mods {
 			for pf in b.parsed_files {
@@ -263,6 +264,7 @@ pub fn (mut b Builder) resolve_deps() {
 		b.table.modules = mods
 		b.parsed_files = reordered_parsed_files
 	}
+}
 
 // graph of all imported modules
 pub fn (b &Builder) import_graph() &depgraph.DepGraph {

vlib/v/checker/checker.v

@@ -271,9 +271,10 @@ pub fn (mut c Checker) check_files(ast_files []&ast.File) {
 	// c.files = ast_files
 	mut has_main_mod_file := false
 	mut has_main_fn := false
+	unsafe {
 	mut files_from_main_module := []&ast.File{}
 	for i in 0 .. ast_files.len {
-		mut file := unsafe { ast_files[i] }
+		mut file := ast_files[i]
 		c.timers.start('checker_check $file.path')
 		c.check(file)
 		if file.mod.name == 'main' {
@@ -302,6 +303,7 @@ pub fn (mut c Checker) check_files(ast_files []&ast.File) {
 			has_main_fn = true
 		}
 	}
+	}
 	c.timers.start('checker_post_process_generic_fns')
 	last_file := c.file
 	// post process generic functions. must be done after all files have been

vlib/v/checker/containers.v

@@ -56,6 +56,13 @@ pub fn (mut c Checker) array_init(mut node ast.ArrayInit) ast.Type {
 			&& c.table.cur_fn.generic_names.len == 0 {
 			c.error('generic struct cannot use in non-generic function', node.pos)
 		}
+
+		// &int{} check
+		if node.elem_type.is_any_kind_of_pointer() && !c.inside_unsafe
+			&& (node.has_len || node.has_cap) {
+			c.warn('arrays of references need to be initialized right away (unless used inside `unsafe`)',
+				node.pos)
+		}
 		return node.typ
 	}
 	if node.is_fixed {

vlib/v/checker/tests/ptr_array_init.out

@@ -0,0 +1,7 @@
+vlib/v/checker/tests/sum.vv:2:14: warning: arrays of references need to be initialized right away (unless used inside `unsafe`)
+    1 | fn main() {
+    2 |     println(*[]&int{len: 1}[0])
+      |              ~~~~~~~
+    3 | }
+    4 |
+

vlib/v/checker/tests/ptr_array_init.vv

@@ -0,0 +1,3 @@
+fn main() {
+    println(*[]&int{len: 1}[0])
+}

vlib/v/gen/c/cgen.v

@@ -4896,6 +4896,7 @@ fn (mut g Gen) write_sorted_types() {
 	defer {
 		g.type_definitions.writeln('// #end sorted_symbols')
 	}
+	unsafe {
 		mut symbols := []&ast.TypeSymbol{cap: g.table.type_symbols.len} // structs that need to be sorted
 		for sym in g.table.type_symbols {
 			if sym.name !in c.builtins {
@@ -4905,6 +4906,7 @@ fn (mut g Gen) write_sorted_types() {
 		sorted_symbols := g.sort_structs(symbols)
 		g.write_types(sorted_symbols)
 	}
+}
 
 fn (mut g Gen) write_types(symbols []&ast.TypeSymbol) {
 	for sym in symbols {
@@ -5186,12 +5188,14 @@ fn (mut g Gen) sort_structs(typesa []&ast.TypeSymbol) []&ast.TypeSymbol {
 			'\nif you feel this is an error, please create a new issue here: https://github.com/vlang/v/issues and tag @joe-conigliaro')
 	}
 	// sort types
+	unsafe {
 		mut sorted_symbols := []&ast.TypeSymbol{cap: dep_graph_sorted.nodes.len}
 		for node in dep_graph_sorted.nodes {
 			sorted_symbols << g.table.sym_by_idx(g.table.type_idxs[node.name])
 		}
 		return sorted_symbols
 	}
+}
 
 [inline]
 fn (g &Gen) nth_stmt_pos(n int) int {

vlib/v/parser/parser.v

@@ -99,7 +99,7 @@ pub mut:
 	vet_errors []vet.Error
 }
 
-__global codegen_files = []&ast.File{}
+__global codegen_files = unsafe { []&ast.File{} }
 
 // for tests
 pub fn parse_stmt(text string, table &ast.Table, scope &ast.Scope) ast.Stmt {
@@ -425,6 +425,7 @@ pub fn parse_files(paths []string, table &ast.Table, pref &pref.Preferences) []&
 		}
 		*/
 	}
+	unsafe {
 		mut files := []&ast.File{cap: paths.len}
 		for path in paths {
 			timers.start('parse_file $path')
@@ -437,6 +438,7 @@ pub fn parse_files(paths []string, table &ast.Table, pref &pref.Preferences) []&
 		}
 		return files
 	}
+}
 
 // codegen allows you to generate V code, so that it can be parsed,
 // checked, markused, cgen-ed etc further, just like user's V code.