diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index a642e663d4..45b7d99821 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -2630,8 +2630,8 @@ static void spapr_phb_placement(sPAPRMachineState *spapr, uint32_t index,
      * 1TiB 64-bit MMIO windows for each PHB.
      */
     const uint64_t base_buid = 0x800000020000000ULL;
-    const int max_phbs =
-        (SPAPR_PCI_LIMIT - SPAPR_PCI_BASE) / SPAPR_PCI_MEM64_WIN_SIZE - 1;
+#define SPAPR_MAX_PHBS ((SPAPR_PCI_LIMIT - SPAPR_PCI_BASE) / \
+                        SPAPR_PCI_MEM64_WIN_SIZE - 1)
     int i;
 
     /* Sanity check natural alignments */
@@ -2640,12 +2640,14 @@ static void spapr_phb_placement(sPAPRMachineState *spapr, uint32_t index,
     QEMU_BUILD_BUG_ON((SPAPR_PCI_MEM64_WIN_SIZE % SPAPR_PCI_MEM32_WIN_SIZE) != 0);
     QEMU_BUILD_BUG_ON((SPAPR_PCI_MEM32_WIN_SIZE % SPAPR_PCI_IO_WIN_SIZE) != 0);
     /* Sanity check bounds */
-    QEMU_BUILD_BUG_ON((max_phbs * SPAPR_PCI_IO_WIN_SIZE) > SPAPR_PCI_MEM32_WIN_SIZE);
-    QEMU_BUILD_BUG_ON((max_phbs * SPAPR_PCI_MEM32_WIN_SIZE) > SPAPR_PCI_MEM64_WIN_SIZE);
+    QEMU_BUILD_BUG_ON((SPAPR_MAX_PHBS * SPAPR_PCI_IO_WIN_SIZE) >
+                      SPAPR_PCI_MEM32_WIN_SIZE);
+    QEMU_BUILD_BUG_ON((SPAPR_MAX_PHBS * SPAPR_PCI_MEM32_WIN_SIZE) >
+                      SPAPR_PCI_MEM64_WIN_SIZE);
 
-    if (index >= max_phbs) {
-        error_setg(errp, "\"index\" for PAPR PHB is too large (max %u)",
-                   max_phbs - 1);
+    if (index >= SPAPR_MAX_PHBS) {
+        error_setg(errp, "\"index\" for PAPR PHB is too large (max %llu)",
+                   SPAPR_MAX_PHBS - 1);
         return;
     }