From 8743509b85537637c8b07647bf8cf72ffec25d1d Mon Sep 17 00:00:00 2001
From: Swastik <swstkbaranwal@gmail.com>
Date: Mon, 30 Dec 2024 01:12:54 +0530
Subject: [PATCH] builtin: add runtime check for `[]Type{cap: negative}`

---
 vlib/builtin/array.v               | 14 ++++++++++++++
 vlib/builtin/array_d_gcboehm_opt.v |  5 +++++
 2 files changed, 19 insertions(+)

diff --git a/vlib/builtin/array.v b/vlib/builtin/array.v
index 0770aae9f2622d..9973b904a559cf 100644
--- a/vlib/builtin/array.v
+++ b/vlib/builtin/array.v
@@ -31,6 +31,7 @@ pub enum ArrayFlags {
 // Internal function, used by V (`nums := []int`)
 fn __new_array(mylen int, cap int, elm_size int) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	arr := array{
 		element_size: elm_size
@@ -43,6 +44,7 @@ fn __new_array(mylen int, cap int, elm_size int) array {
 
 fn __new_array_with_default(mylen int, cap int, elm_size int, val voidptr) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -82,6 +84,7 @@ fn __new_array_with_default(mylen int, cap int, elm_size int, val voidptr) array
 
 fn __new_array_with_multi_default(mylen int, cap int, elm_size int, val voidptr) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -110,6 +113,7 @@ fn __new_array_with_multi_default(mylen int, cap int, elm_size int, val voidptr)
 
 fn __new_array_with_array_default(mylen int, cap int, elm_size int, val array, depth int) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -132,6 +136,7 @@ fn __new_array_with_array_default(mylen int, cap int, elm_size int, val array, d
 
 fn __new_array_with_map_default(mylen int, cap int, elm_size int, val map) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -155,6 +160,7 @@ fn __new_array_with_map_default(mylen int, cap int, elm_size int, val map) array
 // Private function, used by V (`nums := [1, 2, 3]`)
 fn new_array_from_c_array(len int, cap int, elm_size int, c_array voidptr) array {
 	panic_on_negative_len(len)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < len { len } else { cap }
 	arr := array{
 		element_size: elm_size
@@ -170,6 +176,7 @@ fn new_array_from_c_array(len int, cap int, elm_size int, c_array voidptr) array
 // Private function, used by V (`nums := [1, 2, 3] !`)
 fn new_array_from_c_array_no_alloc(len int, cap int, elm_size int, c_array voidptr) array {
 	panic_on_negative_len(len)
+	panic_on_negative_cap(cap)
 	arr := array{
 		element_size: elm_size
 		data:         c_array
@@ -1049,3 +1056,10 @@ fn panic_on_negative_len(len int) {
 		panic('negative .len')
 	}
 }
+
+@[if !no_bounds_checking ?; inline]
+fn panic_on_negative_cap(cap int) {
+	if cap < 0 {
+		panic('negative .cap')
+	}
+}
diff --git a/vlib/builtin/array_d_gcboehm_opt.v b/vlib/builtin/array_d_gcboehm_opt.v
index dffa424f64eb70..05c62774dc62c1 100644
--- a/vlib/builtin/array_d_gcboehm_opt.v
+++ b/vlib/builtin/array_d_gcboehm_opt.v
@@ -7,6 +7,7 @@ module builtin
 
 fn __new_array_noscan(mylen int, cap int, elm_size int) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	arr := array{
 		element_size: elm_size
@@ -19,6 +20,7 @@ fn __new_array_noscan(mylen int, cap int, elm_size int) array {
 
 fn __new_array_with_default_noscan(mylen int, cap int, elm_size int, val voidptr) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -46,6 +48,7 @@ fn __new_array_with_default_noscan(mylen int, cap int, elm_size int, val voidptr
 
 fn __new_array_with_multi_default_noscan(mylen int, cap int, elm_size int, val voidptr) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -63,6 +66,7 @@ fn __new_array_with_multi_default_noscan(mylen int, cap int, elm_size int, val v
 
 fn __new_array_with_array_default_noscan(mylen int, cap int, elm_size int, val array) array {
 	panic_on_negative_len(mylen)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < mylen { mylen } else { cap }
 	mut arr := array{
 		element_size: elm_size
@@ -80,6 +84,7 @@ fn __new_array_with_array_default_noscan(mylen int, cap int, elm_size int, val a
 // Private function, used by V (`nums := [1, 2, 3]`)
 fn new_array_from_c_array_noscan(len int, cap int, elm_size int, c_array voidptr) array {
 	panic_on_negative_len(len)
+	panic_on_negative_cap(cap)
 	cap_ := if cap < len { len } else { cap }
 	arr := array{
 		element_size: elm_size