Fix SDV build

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>

diff --git a/src/xennet/adapter.c b/src/xennet/adapter.c
index 54823d879356a33ed06d273c8b96c56a0f611fc2..81070dc26d715ea65873fdddce2a20c5a70080f9 100644 (file)
--- a/src/xennet/adapter.c
+++ b/src/xennet/adapter.c
@@ -2382,7 +2382,7 @@ __AdapterMatchDistribution(
     Text = VENDOR_NAME_STR;
 
     for (Index = 0; Text[Index] != 0; Index++) {
-        if (!isalnum(Text[Index])) {
+        if (!isalnum((UCHAR)Text[Index])) {
             if (Vendor[Index] != '_') {
                 Match = FALSE;
                 break;
@@ -2528,7 +2528,7 @@ update:
     ASSERT(NT_SUCCESS(status));
 
     for (Index  = 0; Vendor[Index] != '\0'; Index++)
-        if (!isalnum(Vendor[Index]))
+        if (!isalnum((UCHAR)Vendor[Index]))
             Vendor[Index] = '_';
 
     Product = "XENNET";