diff --git a/app/interrupt.c b/app/interrupt.c
index 3927248..927f719 100644
--- a/app/interrupt.c
+++ b/app/interrupt.c
@@ -27,13 +27,13 @@
 #define HLT_OPCODE  0xf4
 
 #ifdef __x86_64__
-#define REG_PREFIX  'r'
-#define REG_DIGITS  16
-#define ADR_DIGITS  12
+#define REG_PREFIX  "r"
+#define REG_DIGITS  "16"
+#define ADR_DIGITS  "12"
 #else
-#define REG_PREFIX  'e'
-#define REG_DIGITS  8
-#define ADR_DIGITS  8
+#define REG_PREFIX  "e"
+#define REG_DIGITS  "8"
+#define ADR_DIGITS  "8"
 #endif
 
 static const char *codes[] = {
@@ -139,31 +139,31 @@ void interrupt(struct trap_regs *trap_regs)
     } else {
         display_pinned_message(2, 0, "Type: %i", trap_regs->vect);
     }
-    display_pinned_message(3, 0, "  PC: %0*x", REG_DIGITS, (uintptr_t)trap_regs->ip);
-    display_pinned_message(4, 0, "  CS: %0*x", REG_DIGITS, (uintptr_t)trap_regs->cs);
-    display_pinned_message(5, 0, "Flag: %0*x", REG_DIGITS, (uintptr_t)trap_regs->flags);
-    display_pinned_message(6, 0, "Code: %0*x", REG_DIGITS, (uintptr_t)trap_regs->code);
-    display_pinned_message(7, 0, "  DS: %0*x", REG_DIGITS, (uintptr_t)trap_regs->ds);
-    display_pinned_message(8, 0, "  ES: %0*x", REG_DIGITS, (uintptr_t)trap_regs->es);
-    display_pinned_message(9, 0, "  SS: %0*x", REG_DIGITS, (uintptr_t)trap_regs->ss);
+    display_pinned_message(3, 0, "  PC: %0" REG_DIGITS "x", (uintptr_t)trap_regs->ip);
+    display_pinned_message(4, 0, "  CS: %0" REG_DIGITS "x", (uintptr_t)trap_regs->cs);
+    display_pinned_message(5, 0, "Flag: %0" REG_DIGITS "x", (uintptr_t)trap_regs->flags);
+    display_pinned_message(6, 0, "Code: %0" REG_DIGITS "x", (uintptr_t)trap_regs->code);
+    display_pinned_message(7, 0, "  DS: %0" REG_DIGITS "x", (uintptr_t)trap_regs->ds);
+    display_pinned_message(8, 0, "  ES: %0" REG_DIGITS "x", (uintptr_t)trap_regs->es);
+    display_pinned_message(9, 0, "  SS: %0" REG_DIGITS "x", (uintptr_t)trap_regs->ss);
     if (trap_regs->vect == 14) {
-        display_pinned_message(9, 0, " Addr: %0*x", REG_DIGITS, address);
+        display_pinned_message(9, 0, " Addr: %0" REG_DIGITS "x", address);
     }
 
-    display_pinned_message(2, 25, "%cax: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->ax);
-    display_pinned_message(3, 25, "%cbx: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->bx);
-    display_pinned_message(4, 25, "%ccx: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->cx);
-    display_pinned_message(5, 25, "%cdx: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->dx);
-    display_pinned_message(6, 25, "%cdi: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->di);
-    display_pinned_message(7, 25, "%csi: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->si);
-    display_pinned_message(8, 25, "%cbp: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->bp);
-    display_pinned_message(9, 25, "%csp: %0*x", REG_PREFIX, REG_DIGITS, (uintptr_t)trap_regs->sp);
+    display_pinned_message(2, 25, REG_PREFIX "ax: %0" REG_DIGITS "x", (uintptr_t)trap_regs->ax);
+    display_pinned_message(3, 25, REG_PREFIX "bx: %0" REG_DIGITS "x", (uintptr_t)trap_regs->bx);
+    display_pinned_message(4, 25, REG_PREFIX "cx: %0" REG_DIGITS "x", (uintptr_t)trap_regs->cx);
+    display_pinned_message(5, 25, REG_PREFIX "dx: %0" REG_DIGITS "x", (uintptr_t)trap_regs->dx);
+    display_pinned_message(6, 25, REG_PREFIX "di: %0" REG_DIGITS "x", (uintptr_t)trap_regs->di);
+    display_pinned_message(7, 25, REG_PREFIX "si: %0" REG_DIGITS "x", (uintptr_t)trap_regs->si);
+    display_pinned_message(8, 25, REG_PREFIX "bp: %0" REG_DIGITS "x", (uintptr_t)trap_regs->bp);
+    display_pinned_message(9, 25, REG_PREFIX "sp: %0" REG_DIGITS "x", (uintptr_t)trap_regs->sp);
 
     display_pinned_message(0, 50, "Stack:");
     for (int i = 0; i < 12; i++) {
         uintptr_t addr = trap_regs->sp + sizeof(reg_t)*(11 - i);
         reg_t data = *(reg_t *)addr;
-        display_pinned_message(1 + i, 50, "%0*x %0*x", ADR_DIGITS, addr, REG_DIGITS, (uintptr_t)data);
+        display_pinned_message(1 + i, 50, "%0" ADR_DIGITS "x %0" REG_DIGITS "x", addr, (uintptr_t)data);
     }
 
     display_pinned_message(11, 0, "CS:PC:");