diff --git a/vlib/builtin/linux_bare/linux_syscalls.v b/vlib/builtin/linux_bare/linux_syscalls.v
index e30aeb533d..d15313955f 100644
--- a/vlib/builtin/linux_bare/linux_syscalls.v
+++ b/vlib/builtin/linux_bare/linux_syscalls.v
@@ -255,7 +255,7 @@ fn sys_close(fd i64) Errno {
 fn sys_mmap(addr &u8, len u64, prot MemProt, flags MapFlags, fildes i64, off u64) (&u8, Errno) {
 	rc := sys_call6(9, u64(addr), len, u64(prot), u64(flags), fildes, off)
 	a, e := split_int_errno(rc)
-	return &u8(a), e
+	return unsafe { &u8(a) }, e
 }
 
 // 11 sys_munmap
@@ -267,7 +267,7 @@ fn sys_munmap(addr voidptr, len u64) Errno {
 fn sys_mremap(old_addr voidptr, old_len u64, new_len u64, flags u64) (&u8, Errno) {
 	rc := sys_call4(25, u64(old_addr), old_len, new_len, flags)
 	a, e := split_int_errno(rc)
-	return &u8(a), e
+	return unsafe { &u8(a) }, e
 }
 
 // 22  sys_pipe
diff --git a/vlib/dlmalloc/dlmalloc.v b/vlib/dlmalloc/dlmalloc.v
index d47576efa2..7a4b69c0a1 100644
--- a/vlib/dlmalloc/dlmalloc.v
+++ b/vlib/dlmalloc/dlmalloc.v
@@ -308,13 +308,13 @@ fn (c &Chunk) mmapped() bool {
 fn (c &Chunk) next() &Chunk {
 	mut me := usize(c)
 	me = me + c.size()
-	return &Chunk(me)
+	return unsafe { &Chunk(me) }
 }
 
 fn (c &Chunk) prev() &Chunk {
 	mut me := usize(c)
 	me = me + c.prev_foot
-	return &Chunk(me)
+	return unsafe { &Chunk(me) }
 }
 
 fn (c &Chunk) cinuse() bool {
@@ -366,11 +366,11 @@ fn (c &Chunk) set_foot(size usize) {
 }
 
 fn (c &Chunk) plus_offset(offset usize) &Chunk {
-	return &Chunk((usize(c) + offset))
+	return unsafe { &Chunk((usize(c) + offset)) }
 }
 
 fn (c &Chunk) minus_offset(offset usize) &Chunk {
-	return &Chunk(usize(c) - offset)
+	return unsafe { &Chunk(usize(c) - offset) }
 }
 
 fn (c &Chunk) to_mem() voidptr {
@@ -379,7 +379,7 @@ fn (c &Chunk) to_mem() voidptr {
 
 fn chunk_from_mem(mem_ voidptr) &Chunk {
 	mem := usize(mem_)
-	return &Chunk((mem - chunk_mem_offset()))
+	return unsafe { &Chunk((mem - chunk_mem_offset())) }
 }
 
 fn (tree &TreeChunk) leftmost_child() &TreeChunk {