Detect more unused assignments for function arguments by marking them as uASSIGNED at the beginning of function body

Author: Daniel-Cortez

source/compiler/sc1.c

@@ -4294,7 +4294,9 @@ static void doarg(char *name,int ident,int offset,int tags[],int numtags,
       argsym->usage|=uREAD;     /* arguments of public functions are always "used" */
       if(argsym->ident==iREFARRAY || argsym->ident==iREFERENCE)
         argsym->usage|=uWRITTEN;
-    }
+    } else if (argsym->ident==iVARIABLE) {
+      argsym->usage|=uASSIGNED;
+    } /* if */
 
     if (fconst)
       argsym->usage|=uCONST;

source/compiler/tests/warning_240.meta

@@ -6,6 +6,7 @@ warning_240.pwn(12) : warning 240: previously assigned value is never used (symb
 warning_240.pwn(14) : warning 204: symbol is assigned a value that is never used: "local_var"
 warning_240.pwn(23) : warning 240: previously assigned value is never used (symbol "local_static_var")
 warning_240.pwn(24) : warning 240: previously assigned value is never used (symbol "local_static_var")
+warning_240.pwn(49) : warning 240: previously assigned value is never used (symbol "arg")
 warning_240.pwn(50) : warning 240: previously assigned value is never used (symbol "arg")
 warning_240.pwn(50) : warning 204: symbol is assigned a value that is never used: "arg"
 """

source/compiler/tests/warning_240.pwn

@@ -46,7 +46,7 @@ test_global_static()
 
 test_arg(arg)
 {
-	arg = 0;
+	arg = 0; // warning 240
 	arg = 1; // warning 240, warning 204
 }