diff --git a/cmd/zfs/zfs_main.c b/cmd/zfs/zfs_main.c
index 87f83ab394..179f04aaba 100644
--- a/cmd/zfs/zfs_main.c
+++ b/cmd/zfs/zfs_main.c
@@ -1503,7 +1503,7 @@ zfs_do_upgrade(int argc, char **argv)
 	boolean_t showversions = B_FALSE;
 	int ret;
 	upgrade_cbdata_t cb = { 0 };
-	char c;
+	signed char c;
 	int flags = ZFS_ITER_ARGS_CAN_BE_PATHS;
 
 	/* check options */
@@ -2259,7 +2259,7 @@ zfs_do_snapshot(int argc, char **argv)
 {
 	boolean_t recursive = B_FALSE;
 	int ret;
-	char c;
+	signed char c;
 	nvlist_t *props;
 
 	if (nvlist_alloc(&props, NV_UNIQUE_NAME, 0) != 0) {
diff --git a/lib/libspl/include/sys/isa_defs.h b/lib/libspl/include/sys/isa_defs.h
index bf93db4782..65e695adeb 100644
--- a/lib/libspl/include/sys/isa_defs.h
+++ b/lib/libspl/include/sys/isa_defs.h
@@ -69,7 +69,7 @@ extern "C" {
 
 #define        _SUNOS_VTOC_16
 
-/* powerpc (ppc64) arch specific defines */
+/* powerpc arch specific defines */
 #elif defined(__powerpc) || defined(__powerpc__)
 
 #if !defined(__powerpc)
@@ -81,7 +81,11 @@ extern "C" {
 #endif
 
 #if !defined(_LP64)
+#ifdef __powerpc64__
 #define _LP64
+#else
+#define _LP32
+#endif
 #endif
 
 #define        _SUNOS_VTOC_16