diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 6dc9aed31..77d4447f5 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -651,6 +651,8 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 			// dumpAst(NULL, ">   ");
 			log_error("Index in generate block prefix syntax at %s:%d is not constant!\n", filename.c_str(), linenum);
 		}
+		if (children[1]->type == AST_PREFIX)
+			children[1]->simplify(const_fold, at_zero, in_lvalue, stage, width_hint, sign_hint, in_param);
 		log_assert(children[1]->type == AST_IDENTIFIER);
 		newNode = children[1]->clone();
 		const char *second_part = children[1]->str.c_str();