diff --git a/nc_test/test_read.m4 b/nc_test/test_read.m4
index 77009f311..a091b3fe7 100644
--- a/nc_test/test_read.m4
+++ b/nc_test/test_read.m4
@@ -33,10 +33,6 @@ dnl
 #endif
 #include <errno.h>     /* errno, strerror() */
 
-#ifndef HAVE_SSIZE_T
-typedef int ssize_t;
-#endif
-
 #include "tests.h"
 
 define(`EXPECT_ERR',`error("expecting $1 but got %s",nc_err_code_name($2));')dnl
diff --git a/nc_test/test_write.m4 b/nc_test/test_write.m4
index 1c47f10d2..f43294f38 100644
--- a/nc_test/test_write.m4
+++ b/nc_test/test_write.m4
@@ -35,10 +35,6 @@ dnl
 #include "tests.h"
 #include "math.h"
 
-#ifndef HAVE_SSIZE_T
-typedef int ssize_t;
-#endif
-
 define(`EXPECT_ERR',`error("expecting $1 but got %s",nc_err_code_name($2));')dnl
 
 define(`IntType', `ifdef(`PNETCDF',`MPI_Offset',`size_t')')dnl
diff --git a/nc_test/tests.h b/nc_test/tests.h
index 2e24295a5..908fabcd3 100644
--- a/nc_test/tests.h
+++ b/nc_test/tests.h
@@ -18,6 +18,10 @@
 #endif
 #include "error.h"
 
+#ifndef HAVE_SSIZE_T
+typedef int ssize_t;
+#endif
+
 #if defined(_CRAY) && !defined(_CRAYIEEE) && !defined(__crayx1)
 #define CRAYFLOAT 1 /* CRAY Floating point */
 #elif defined(_SX) && defined(_FLOAT2)	/* NEC SUPER-UX in CRAY mode */