From 776233c71814ddee8cf321f9b69b01241e5dc00a Mon Sep 17 00:00:00 2001
From: eck <none@none>
Date: Mon, 13 Nov 1989 14:01:50 +0000
Subject: [PATCH] improved qualifier checking

---
 lang/cem/cemcom.ansi/ch3.c    | 51 ++++++++++++++++++-----------------
 lang/cem/cemcom.ansi/ch3bin.c |  4 +--
 lang/cem/cemcom.ansi/idf.c    |  2 +-
 3 files changed, 29 insertions(+), 28 deletions(-)

diff --git a/lang/cem/cemcom.ansi/ch3.c b/lang/cem/cemcom.ansi/ch3.c
index ecec52de5..71c9aad4b 100644
--- a/lang/cem/cemcom.ansi/ch3.c
+++ b/lang/cem/cemcom.ansi/ch3.c
@@ -170,6 +170,7 @@ ch3cast(expp, oper, tp)
 		expression of class Type.
 	*/
 	register struct type *oldtp;
+	int qual_lev;
 
 	if (oper == RETURN && tp->tp_fund == VOID) {
 		expr_strict(*expp, "return <expression> in function returning void");
@@ -195,8 +196,19 @@ ch3cast(expp, oper, tp)
 	}
 	else
 #endif NOBITFIELD
-	if (equal_type(tp, oldtp, oper != CAST)) {
+	if (oper == CASTAB || oper == '=' || oper == RETURN) {
+		qual_lev = -2;
+	} else if (oper == CAST) qual_lev = -999;	/* ??? hack */
+	else qual_lev = -1;
+
+	if (equal_type(tp, oldtp, qual_lev)) {
 		/* life is easy */
+		if (qual_lev == -2 && tp->tp_fund == POINTER) {
+			if ((tp->tp_up->tp_typequal & oldtp->tp_up->tp_typequal)
+			    != oldtp->tp_up->tp_typequal) {
+				expr_strict( *expp, "qualifier error");
+			}
+		}
 		(*expp)->ex_type = tp;	/* so qualifiers are allright */
 	}
 	else
@@ -336,11 +348,11 @@ ch3cast(expp, oper, tp)
 
 /*	Determine whether two types are equal.
 */
-equal_type(tp, otp, check_qual)
+equal_type(tp, otp, qual_lev)
 	register struct type *tp, *otp;
-	int check_qual;
+	int qual_lev;
 {
-	if (tp == otp)
+	 if (tp == otp)
 		return 1;
 	if (!tp
 	    || !otp
@@ -352,6 +364,10 @@ equal_type(tp, otp, check_qual)
 		if (tp->tp_size != otp->tp_size)
 			return 0;
 	}
+	if (qual_lev >= 0) {
+		if (tp->tp_typequal != otp->tp_typequal)
+			strict("illegal qualifiers");
+	}
 
 	switch (tp->tp_fund) {
 
@@ -367,7 +383,7 @@ equal_type(tp, otp, check_qual)
 			if (!legal_mixture(tp, otp))
 				return 0;
 		}
-		return equal_type(tp->tp_up, otp->tp_up, 0);
+		return equal_type(tp->tp_up, otp->tp_up, qual_lev + 1);
 
 	case ARRAY:
 		/*	If one type is an array of known size, the composite
@@ -376,28 +392,13 @@ equal_type(tp, otp, check_qual)
 		if (tp->tp_size != otp->tp_size &&
 		     (tp->tp_size != -1 && otp->tp_size != -1))
 			return 0;
-		return equal_type(tp->tp_up, otp->tp_up, check_qual);
+		return equal_type(tp->tp_up, otp->tp_up, qual_lev); /* ??? +1 */
 
 	case POINTER:
-		if (equal_type(tp->tp_up, otp->tp_up, check_qual)) {
-		    if (check_qual) {
-			if (otp->tp_up->tp_typequal & TQ_CONST) {
-			    if (!(tp->tp_up->tp_typequal & TQ_CONST)) {
-				strict("illegal use of pointer to const object");
-			    }
-			}
-			if (otp->tp_up->tp_typequal & TQ_VOLATILE) {
-			    if (!(tp->tp_up->tp_typequal & TQ_VOLATILE)) {
-				strict("illegal use of pointer to volatile object");
-			    }
-			}
-		    }
-		    return 1;
-		}
-		else return 0;
+		return equal_type(tp->tp_up, otp->tp_up, qual_lev + 1);
 
 	case FIELD:
-		return equal_type(tp->tp_up, otp->tp_up, check_qual);
+		return equal_type(tp->tp_up, otp->tp_up, qual_lev); /* ??? +1 */
 
 	case STRUCT:
 	case UNION:
@@ -426,7 +427,7 @@ check_pseudoproto(pl, opl)
 		return 0;
 	}
 	while (pl && opl) {
-	    if (!equal_type(pl->pl_type, opl->pl_type, 0)) {
+	    if (!equal_type(pl->pl_type, opl->pl_type, -1)) {
 		if (!(pl->pl_flag & PL_ERRGIVEN)
 		    && !(opl->pl_flag & PL_ERRGIVEN))
 			error("incorrect type for parameter %s of definition",
@@ -500,7 +501,7 @@ equal_proto(pl, opl)
 	while ( pl && opl) {
 
 	    if ((pl->pl_flag & ~PL_ERRGIVEN) != (opl->pl_flag & ~PL_ERRGIVEN) ||
-	        !equal_type(pl->pl_type, opl->pl_type, 0))
+	        !equal_type(pl->pl_type, opl->pl_type, -1))
 		return 0;
 
 	    pl = pl->next;
diff --git a/lang/cem/cemcom.ansi/ch3bin.c b/lang/cem/cemcom.ansi/ch3bin.c
index 4d380120a..c1d5ab5f4 100644
--- a/lang/cem/cemcom.ansi/ch3bin.c
+++ b/lang/cem/cemcom.ansi/ch3bin.c
@@ -236,7 +236,7 @@ ch3bin(expp, oper, expr)
 		if (	is_struct_or_union(expp_tp->tp_fund)
 		||	is_struct_or_union(expr->ex_type->tp_fund)
 		)	{
-			if (!equal_type(expp_tp, expr->ex_type, 0))
+			if (!equal_type(expp_tp, expr->ex_type, -1))
 				expr_error(*expp, "illegal balance");
 		}
 		else
@@ -284,7 +284,7 @@ pntminuspnt(expp, oper, expr)
 	*/
 	struct type *up_type = (*expp)->ex_type->tp_up;
 
-	if (!equal_type(up_type, expr->ex_type->tp_up, 0)) {
+	if (!equal_type(up_type, expr->ex_type->tp_up, -1)) {
 		expr_error(*expp, "subtracting incompatible pointers");
 		free_expression(expr);
 		erroneous2int(expp);
diff --git a/lang/cem/cemcom.ansi/idf.c b/lang/cem/cemcom.ansi/idf.c
index 5ca36b982..e3da45f2a 100644
--- a/lang/cem/cemcom.ansi/idf.c
+++ b/lang/cem/cemcom.ansi/idf.c
@@ -610,7 +610,7 @@ check_formals(idf, dc)
 		}
 		while(fm && pl) {
 		    if (!equal_type(promoted_type(fm->fm_idf->id_def->df_type)
-					, pl->pl_type, 0)) {
+					, pl->pl_type, -1)) {
 			if (!(pl->pl_flag & PL_ERRGIVEN))
 			    error("incorrect type for parameter %s"
 						, fm->fm_idf->id_text);
-- 
2.34.1