Don't go off into infinite loops when some undefined program

updates a variable where the only def is the update itself.

Testcase from Alexey Dobriyan

1 files changed, 7 insertions, 0 deletions

diff --git a/simplify.c b/simplify.c
index 53c5188..8a8d450 100644
--- a/simplify.c
+++ b/simplify.c
@@ -441,6 +441,13 @@ static int simplify_memop(struct instruction *insn)
 	return 0;
 
 offset:
+	/* Invalid code */
+	if (new == addr) {
+		if (new == VOID)
+			return 0;
+		new = VOID;
+		warning(insn->bb->pos, "crazy programmer");
+	}
 	insn->offset += off->value;
 	use_pseudo(new, &insn->src);
 	remove_usage(addr, &insn->src);