diff --git a/tests/incr.test b/tests/incr.test
index ff328b710ce..48d64deebd6 100644
--- a/tests/incr.test
+++ b/tests/incr.test
@@ -237,6 +237,7 @@ test incr-1.30 {TclCompileIncrCmd: array var, braced (no subs)} -setup {
 } -result 5
 
 test incr-1.31 {no overflow in TclCompileIncrCmd and Tcl_IncrObjCmd, bug [7179c6724cd38271]} {
+    set res [list]
     # TclCompileIncrCmd: compiled incr TEBC with immutable constant offs (INST_INCR_*_IMM instructions):
     lappend res [set i 0; incr i 0x7FFFFFFF]
     lappend res [set i 0; incr i 0xFFFFFF80]