diff --git a/src/racket/include/scheme.h b/src/racket/include/scheme.h
index 7dffd01922..8a5c384002 100644
--- a/src/racket/include/scheme.h
+++ b/src/racket/include/scheme.h
@@ -136,6 +136,7 @@ START_XFORM_SUSPEND;
 #include <stdlib.h>
 #include <string.h>
 #include <stddef.h>
+#include <stdint.h>
 
 #ifdef MZ_XFORM
 END_XFORM_SUSPEND;
diff --git a/src/racket/src/schemef.h b/src/racket/src/schemef.h
index 381316f477..6f385fcaab 100644
--- a/src/racket/src/schemef.h
+++ b/src/racket/src/schemef.h
@@ -573,8 +573,8 @@ MZ_EXTERN Scheme_Object *scheme_make_integer_value(intptr_t i);
 MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_unsigned(uintptr_t i);
 MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_long_long(mzlonglong i);
 MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_unsigned_long_long(umzlonglong i);
-MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_long_halves(unsigned long lowhalf, unsigned long hihalf);
-MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_unsigned_long_halves(unsigned long lowhalf, unsigned long hihalf);
+MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_long_halves(uintptr_t lowhalf, uintptr_t hihalf);
+MZ_EXTERN Scheme_Object *scheme_make_integer_value_from_unsigned_long_halves(uintptr_t lowhalf, uintptr_t hihalf);
 MZ_EXTERN Scheme_Object *scheme_make_double(double d);
 #ifdef MZ_USE_SINGLE_FLOATS
 MZ_EXTERN Scheme_Object *scheme_make_float(float f) ;