diff --git a/arch/x86/gen_idt.py b/arch/x86/gen_idt.py
index 8120a702477..8d8bab0270b 100755
--- a/arch/x86/gen_idt.py
+++ b/arch/x86/gen_idt.py
@@ -274,9 +274,8 @@ def create_irq_vectors_allocated(vectors, spur_code, spur_nocode, filename):
     # interrupt handlers installed, they are free for runtime installation
     # of interrupts
     num_chars = (len(vectors) + 7) // 8
-    vbits = [0 for i in range(num_chars)]
-    for i in range(len(vectors)):
-        handler, _, _ = vectors[i]
+    vbits = num_chars*[0]
+    for i, (handler, _, _) in enumerate(vectors):
         if handler not in (spur_code, spur_nocode):
             continue