diff --git a/conf/cf-lex.l b/conf/cf-lex.l
index a43f9eb..408fa93 100644
--- a/conf/cf-lex.l
+++ b/conf/cf-lex.l
@@ -129,10 +129,10 @@ include   ^{WHITE}*include{WHITE}*\".*\"{WHITE}*;
 
 0x{XIGIT}+ {
   char *e;
-  long int l;
+  unsigned long int l;
   errno = 0;
   l = strtoul(yytext+2, &e, 16);
-  if (e && *e || errno == ERANGE || (long int)(int) l != l)
+  if (e && *e || errno == ERANGE || (unsigned long int)(unsigned int) l != l)
     cf_error("Number out of range");
   cf_lval.i = l;
   return NUM;
@@ -140,10 +140,10 @@ include   ^{WHITE}*include{WHITE}*\".*\"{WHITE}*;
 
 {DIGIT}+ {
   char *e;
-  long int l;
+  unsigned long int l;
   errno = 0;
   l = strtoul(yytext, &e, 10);
-  if (e && *e || errno == ERANGE || (long int)(int) l != l)
+  if (e && *e || errno == ERANGE || (unsigned long int)(unsigned int) l != l)
     cf_error("Number out of range");
   cf_lval.i = l;
   return NUM;