diff --git a/lang/src/vec.asm b/lang/src/vec.asm
index 2523cf4..e9f6748 100644
--- a/lang/src/vec.asm
+++ b/lang/src/vec.asm
@@ -244,3 +244,36 @@ vec_try_grow:
     xor rax, rax
     ret
 
+;; rdi: pointer to Vec struct
+vec_drop:
+    push r12
+    push r13
+    push r14
+    push rdi
+    ; if let Some(drop) = vec.drop {
+    mov r12, [rdi + 32]
+    test r12, r12
+    je .ret
+    ;   for i in 0..vec.len {
+    xor r13, r13
+    mov r14, [rdi + 8]    ; len
+.loop:
+    cmp r13, r14
+    jge .ret
+    mov rdi, [rsp]
+    ;     drop(&mut vec.data[i * vec.item_size..(i + 1) * vec.item_size]);
+    imul r13, [rdi + 24] ; i * item_size
+    mov rdi, [rdi]      ; data
+    add rdi, rax
+    call r12
+    inc r13
+    jmp .loop
+    ;   }
+    ; }
+    ; free(vec.data);
+.ret:
+    pop rdi
+    pop r14
+    pop r13
+    pop r12
+    ret