1 files changed, 3 insertions, 3 deletions

diff --git a/source/components/utilities/utprint.c b/source/components/utilities/utprint.c
index 832d04fd35c2..6d7b87cd3e8a 100644
--- a/source/components/utilities/utprint.c
+++ b/source/components/utilities/utprint.c
@@ -227,7 +227,7 @@ AcpiUtScanNumber (
     UINT64                  Number = 0;
 
 
-    while (isdigit (*String))
+    while (isdigit ((int) *String))
     {
         Number *= 10;
         Number += *(String++) - '0';
@@ -505,7 +505,7 @@ AcpiUtVsnprintf (
         /* Process width */
 
         Width = -1;
-        if (isdigit (*Format))
+        if (isdigit ((int) *Format))
         {
             Format = AcpiUtScanNumber (Format, &Number);
             Width = (INT32) Number;
@@ -527,7 +527,7 @@ AcpiUtVsnprintf (
         if (*Format == '.')
         {
             ++Format;
-            if (isdigit(*Format))
+            if (isdigit ((int) *Format))
             {
                 Format = AcpiUtScanNumber (Format, &Number);
                 Precision = (INT32) Number;