diff --git a/ext/opcache/jit/zend_jit_trace.c b/ext/opcache/jit/zend_jit_trace.c
index 4ce2a6dbad01f..2576894d1db07 100644
--- a/ext/opcache/jit/zend_jit_trace.c
+++ b/ext/opcache/jit/zend_jit_trace.c
@@ -774,7 +774,7 @@ static int find_call_num_args(zend_jit_trace_rec *p)
 static int is_checked_guard(const zend_ssa *tssa, const zend_op **ssa_opcodes, uint32_t var, uint32_t phi_var)
 {
 	if ((tssa->var_info[phi_var].type & MAY_BE_ANY) == MAY_BE_LONG) {
-		uint32_t idx = tssa->vars[var].definition;
+		int32_t idx = tssa->vars[var].definition;
 
 		if (idx >= 0) {
 			if (tssa->ops[idx].op1_def == var) {