From ce17cff7f725fef6ed670ecf02ae92ee4dba79dc Mon Sep 17 00:00:00 2001
From: Yashas <yashas_2010@yahoo.com>
Date: Fri, 8 Jun 2018 21:17:11 +0530
Subject: [PATCH] trigger destructor not implemented error

```
#include <a_samp>

forward operator~(Error:right[], size);
main() {
    new Error:e;
}
```

```
CODE 0    ; 0
;program exit point
    halt 0

    proc    ; main
    ; line 4
    ; line 5
    break    ; c
    ;$lcl e fffffffc
    push.c 0
    ;$exp
    push.pri
    push.c 1
    addr.pri fffffffc
    push.pri
    push.c 8
    call .~4000000f    ; operator~(Error:)
    pop.pri
    stack 4
    zero.pri
    retn

STKSIZE 1000
```

The compiler tries to call a non-existent function. This commit instead throws "function not implemented" error when destructor definition is missing.
---
 source/compiler/sc1.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/source/compiler/sc1.c b/source/compiler/sc1.c
index 116a65e..655678b 100644
--- a/source/compiler/sc1.c
+++ b/source/compiler/sc1.c
@@ -4967,6 +4967,14 @@ static void destructsymbols(symbol *root,int level)
       /* check that the '~' operator is defined for this tag */
       operator_symname(symbolname,"~",sym->tag,0,1,0);
       if ((opsym=findglb(symbolname,sGLOBAL))!=NULL) {
+        if ((opsym->usage & uMISSING)!=0 || (opsym->usage & uPROTOTYPED)==0) {
+          char symname[2*sNAMEMAX+16];  /* allow space for user defined operators */
+          funcdisplayname(symname,opsym->name);
+          if ((opsym->usage & uMISSING)!=0)
+            error(4,symname);           /* function not defined */
+          if ((opsym->usage & uPROTOTYPED)==0)
+            error(71,symname);          /* operator must be declared before use */
+        } /* if */
         /* save PRI, in case of a return statment */
         if (!savepri) {
           pushreg(sPRI);        /* right-hand operand is in PRI */