cast const ptr: refactor/remove unneeded code

- hSymbCheckConstAssignFuncPtr() can be private, and only checks the function pointer sub type.  The top level check is called by symbCheckConstAssign()
- only symbCheckConstAssign() now clears the error/warning message
- symbCheckConstAssignTopLevel() still needed for now otherwise const warnings related to function pointer data types become errors

Author: jayrm

src/compiler/symb-proc.bas

@@ -1676,7 +1676,7 @@ private function hCalcTypesDiff _
 			''   it's a DEREF or not (it can all be treated as string)
 			'' - disallow other args (passing BYVAL explicitly
 			''   should be handled by caller already)
-			select case( typeGetDtAndPtrOnly( param_dtype ) )
+			select case( param_dtype )
 			case FB_DATATYPE_CHAR
 				select case( arg_dtype )
 				case FB_DATATYPE_CHAR
@@ -2383,7 +2383,7 @@ private function hCheckCastOvl _
 		if( proc_subtype = to_subtype ) then
 
 			'' same const?
-			if( proc_subtype = to_subtype ) then
+			if( proc_dtype = to_dtype ) then
 				return FB_OVLPROC_FULLMATCH
 			end if
 

src/compiler/symb.bas

@@ -1885,9 +1885,6 @@ function symbCheckConstAssignTopLevel _
 	dim as integer i = any, lcount = any, rcount = any, rmatches = any
 	dim as integer lconst = any, rconst = any
 
-	errmsg = 0
-	wrnmsg = 0
-
 	''
 	'' Toplevel const:
 	''
@@ -1925,14 +1922,9 @@ function symbCheckConstAssignTopLevel _
 	function = FALSE
 	matches = 0
 
-	'' neither is a function pointer?
-	if( ( typeGetDtOnly( ldType ) <> FB_DATATYPE_FUNCTION ) and ( typeGetDtOnly( rdType ) <> FB_DATATYPE_FUNCTION ) ) then
-
-		'' no consts? short-circuit
-		if( (typeGetConstMask( ldtype ) or typeGetConstMask( rdtype )) = 0 ) then
-			return TRUE
-		end if
-
+	'' no consts? short-circuit
+	if( (typeGetConstMask( ldtype ) or typeGetConstMask( rdtype )) = 0 ) then
+		return TRUE
 	end if
 
 	'' vararg? they aren't type safe anyway
@@ -1987,7 +1979,7 @@ function symbCheckConstAssignTopLevel _
 	function = TRUE
 end function
 
-function symbCheckConstAssignFuncPtr _
+function hSymbCheckConstAssignFuncPtr _
 	( _
 		byval ldtype as FB_DATATYPE, _
 		byval rdtype as FB_DATATYPE, _
@@ -2005,19 +1997,12 @@ function symbCheckConstAssignFuncPtr _
 
 	function = FALSE
 
-	errmsg = FB_ERRMSG_OK '' FB_ERRMSG
-	wrnmsg = 0            '' FB_WARNINGMSG
 
 	assert( typeGetDtOnly( ldType ) = FB_DATATYPE_FUNCTION )
 	assert( typeGetDtOnly( rdType ) = FB_DATATYPE_FUNCTION )
 	assert( symbIsProc( lsubtype ) )
 	assert( symbIsProc( rsubtype ) )
 
-	'' not a function pointer?
-	if( ( typeGetDtOnly( ldType ) <> FB_DATATYPE_FUNCTION ) or ( typeGetDtOnly( rdType ) <> FB_DATATYPE_FUNCTION ) ) then
-		exit function
-	end if
-
 	'' Return warnings even though some checks are not CONSTness releated.  We could
 	'' promote them to errors, but that will cause many tests to break, and really, we are
 	'' not specifically checking the assignment, but rather the function pointer compatibility.
@@ -2052,11 +2037,6 @@ function symbCheckConstAssignFuncPtr _
 		exit function
 	end if
 
-	'' check top level
-	if( symbCheckConstAssignTopLevel( ldtype, rdtype, lsubtype, rsubtype, mode, matches, errmsg, wrnmsg ) = FALSE ) then
-		exit function
-	end if
-
 	'' Check each parameter
 	var lparam = symbGetProcHeadParam( lsubtype )
 	var rparam = symbGetProcHeadParam( rsubtype )
@@ -2096,13 +2076,23 @@ function symbCheckConstAssign _
 		byref wrnmsg as FB_WARNINGMSG = 0 _
 	) as integer
 
-	'' both types function pointer?
-	if( ( typeGetDtOnly( ldType ) = FB_DATATYPE_FUNCTION ) and ( typeGetDtOnly( rdType ) = FB_DATATYPE_FUNCTION ) ) then
-		return symbCheckConstAssignFuncPtr( ldtype, rdtype, lsubtype, rsubtype, mode, matches, errmsg, wrnmsg )
-	else
-		return symbCheckConstAssignTopLevel( ldtype, rdtype, lsubtype, rsubtype, mode, matches, errmsg, wrnmsg )
+	dim ret as integer = any
+
+	errmsg = FB_ERRMSG_OK '' FB_ERRMSG
+	wrnmsg = 0            '' FB_WARNINGMSG
+	
+	'' check top-level const
+	ret = symbCheckConstAssignTopLevel( ldtype, rdtype, lsubtype, rsubtype, mode, matches, errmsg, wrnmsg )
+	
+	if( ret ) then
+		'' both types function pointer?
+		if( ( typeGetDtOnly( ldType ) = FB_DATATYPE_FUNCTION ) and ( typeGetDtOnly( rdType ) = FB_DATATYPE_FUNCTION ) ) then
+			ret and= hSymbCheckConstAssignFuncPtr( ldtype, rdtype, lsubtype, rsubtype, mode, matches, errmsg, wrnmsg )
+		end if
 	end if
 
+	function = ret
+
 end function
 
 private sub hForEachGlobal _

src/compiler/symb.bi

@@ -1883,18 +1883,6 @@ declare function symbCheckConstAssignTopLevel _
 		byref wrnmsg as FB_WARNINGMSG = 0 _
 	) as integer
 
-declare function symbCheckConstAssignFuncPtr _
-	( _
-		byval ldtype as FB_DATATYPE, _
-		byval rdtype as FB_DATATYPE, _
-		byval lsubtype as FBSYMBOL ptr, _
-		byval rsubtype as FBSYMBOL ptr, _
-		byval mode as FB_PARAMMODE = 0, _
-		byref matches as integer = 0, _
-		byref errmsg as FB_ERRMSG = 0, _
-		byref wrnmsg as FB_WARNINGMSG = 0 _
-	) as integer
-
 declare function symbCheckConstAssign _
 	( _
 		byval ldtype as FB_DATATYPE, _