scc

commit 33787455afaea0e22d89176ede170941766a9bd4
parent ea6d8cf4e6d83ca32ce98443dc939ec897daf6b7
Author: Roberto E. Vargas Caballero <k0ga@shike2.net>
Date:   Mon, 11 May 2026 20:55:40 +0200

cc1: Check type of array designator index

The expression between [ ] must an integer constant expression,
and the function iconstexpr() returns NULL in that case and
it has to be checked to give the proper error message.

Diffstat:
M
src/cmd/scc-cc/cc1/init.c
 | 
11
+++++++++--

1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/src/cmd/scc-cc/cc1/init.c b/src/cmd/scc-cc/cc1/init.c
@@ -31,14 +31,21 @@ int disstring;
 static long long
 arydesig(Type *tp, Init *ip)
 {
+
 	long long npos;
 	Node *np;
 
 	if (tp->op != ARY)
 		errorp("array index in non-array initializer");
+
 	next();
-	np = iconstexpr();
-	npos = np->sym->u.i;
+	if ((np = iconstexpr()) == NULL) {
+		errorp("array index in initializer not of integer type");
+		npos = 0;
+	} else {
+		npos = np->sym->u.i;
+	}
+
 	if (npos < 0 || (tp->prop & TDEFINED) && npos >= tp->n.elem) {
 		errorp("array index in initializer exceeds array bounds");
 		npos = 0;