scc

commit c21d1c13987c7082c5157726dcfa4f9715773c5d
parent 0bb819c2423f68687ac0a6376ce6f1a6967a5a51
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Tue, 21 Feb 2017 17:08:45 +0100

[cc1] Fix pcompare() with NULL operands

Pcompare() was using eqtype() to see if the type of the operands
were compatible, but this is an error because a null pointer
can be compared to any pointer. For this reason the correct
code must use convert() which currently deals with all the
possible combinations

Diffstat:
M
cc1/expr.c
 | 
19
++++++-------------
M
tests/execute/scc-tests.lst
 | 
1
+

2 files changed, 7 insertions(+), 13 deletions(-)
diff --git a/cc1/expr.c b/cc1/expr.c
@@ -351,23 +351,16 @@ arithmetic(int op, Node *lp, Node *rp)
 static Node *
 pcompare(int op, Node *lp, Node *rp)
 {
-	Node *np;
-	int err = 0;
+	Node *np, *p;
 
 	if (lp->type->prop & TINTEGER)
 		XCHG(lp, rp, np);
+	else if (eqtype(lp->type, pvoidtype, 1))
+		XCHG(lp, rp, np);
 
-	if (rp->type->prop & TINTEGER) {
-		if (!cmpnode(rp, 0))
-			err = 1;
-		rp = convert(rp, pvoidtype, 1);
-	} else if (rp->type->op == PTR) {
-		if (!eqtype(lp->type, rp->type, 1))
-			err = 1;
-	} else {
-		err = 1;
-	}
-	if (err)
+	if ((p = convert(rp, lp->type, 0)) != NULL)
+		rp = p;
+	else
 		errorp("incompatible types in comparison");
 	return node(op, inttype, lp, rp);
 }
diff --git a/tests/execute/scc-tests.lst b/tests/execute/scc-tests.lst
@@ -105,3 +105,4 @@
 0112-cond.c
 0113-externredecl.c
 0114-shortassig.c
+0115-null-comparision.c