do not allow calloc(0)

vlib/builtin/array.v

@@ -18,11 +18,12 @@ pub:
 
 // Private function, used by V (`nums := []int`)
 fn new_array(mylen, cap, elm_size int) array {
+	cap_ := if cap == 0 { 1 } else { cap }
 	arr := array {
 		len: mylen
 		cap: cap
 		element_size: elm_size
-		data: calloc(cap * elm_size)
+		data: calloc(cap_ * elm_size)
 	}
 	return arr
 }
@@ -36,11 +37,12 @@ pub fn make(len, cap, elm_size int) array {
 
 // Private function, used by V (`nums := [1, 2, 3]`)
 fn new_array_from_c_array(len, cap, elm_size int, c_array voidptr) array {
+	cap_ := if cap == 0 { 1 } else { cap }
 	arr := array {
 		len: len
 		cap: cap
 		element_size: elm_size
-		data: calloc(cap * elm_size)
+		data: calloc(cap_ * elm_size)
 	}
 	// TODO Write all memory functions (like memcpy) in V
 	C.memcpy(arr.data, c_array, len * elm_size)
@@ -96,11 +98,15 @@ pub fn (a array) repeat(nr_repeats int) array {
 	if nr_repeats < 0 {
 		panic('array.repeat: count is negative (count == $nr_repeats)')
 	}
+	mut size := nr_repeats * a.len * a.element_size
+	if size == 0 {
+		size = a.element_size
+	}
 	arr := array {
 		len: nr_repeats * a.len
 		cap: nr_repeats * a.len
 		element_size: a.element_size
-		data: calloc(nr_repeats * a.len * a.element_size)
+		data: calloc(size)
 	}
 	for i := 0; i < nr_repeats; i++ {
 		C.memcpy(arr.data + i * a.len * a.element_size, a.data, a.len * a.element_size)
@@ -267,11 +273,15 @@ pub fn (a array) reverse() array {
 
 // array.clone returns an independent copy of a given array
 pub fn (a array) clone() array {
+	mut size := a.cap * a.element_size
+	if size == 0 {
+		size++
+	}
 	arr := array {
 		len: a.len
 		cap: a.cap
 		element_size: a.element_size
-		data: calloc(a.cap * a.element_size)
+		data: calloc(size)
 	}
 	C.memcpy(arr.data, a.data, a.cap * a.element_size)
 	return arr

vlib/builtin/builtin.v

@@ -106,7 +106,7 @@ __global nr_mallocs int = 0
 [unsafe_fn]
 pub fn malloc(n int) byteptr {
 	if n <= 0 {
-		panic('malloc(<0)')
+		panic('malloc(<=0)')
 	}
 	$if prealloc {
 		res := g_m2_ptr
@@ -136,8 +136,8 @@ TODO
 }
 
 pub fn calloc(n int) byteptr {
-	if n < 0 {
-		panic('calloc(<0)')
+	if n <= 0 {
+		panic('calloc(<=0)')
 	}
 	return C.calloc(n, 1)
 }

vlib/builtin/option.v

@@ -4,6 +4,16 @@
 
 module builtin
 
+/*
+struct Option2<T> {
+	data T
+	error string
+	ecode int
+	ok bool
+	is_none bool
+}
+*/
+
 struct Option {
 	data     [300]byte
 	error    string

vlib/compiler/fn.v

@@ -403,6 +403,7 @@ fn (p mut Parser) fn_decl() {
 	// Register ?option type for return value and args
 	if typ.starts_with('Option_') {
 		p.cgen.typedefs << 'typedef Option $typ;'
+		//p.cgen.typedefs << 'typedef struct Option_$typ Option_$typ'
 	}
 	for arg in f.args {
 		if arg.typ.starts_with('Option_') {