[subset] Remove hb_subset(). Leaving just hb_subset_or_fail().
diff --git a/test/api/hb-subset-test.h b/test/api/hb-subset-test.h
index 91968c3..1fc5a48 100644
--- a/test/api/hb-subset-test.h
+++ b/test/api/hb-subset-test.h
@@ -83,7 +83,7 @@
 hb_subset_test_create_subset (hb_face_t *source,
 			      hb_subset_input_t *input)
 {
-  hb_face_t *subset = hb_subset (source, input);
+  hb_face_t *subset = hb_subset_or_fail (source, input);
   g_assert (subset);
 
   hb_subset_input_destroy (input);
diff --git a/test/api/test-subset-drop-tables.c b/test/api/test-subset-drop-tables.c
index e234080..b2c453a 100644
--- a/test/api/test-subset-drop-tables.c
+++ b/test/api/test-subset-drop-tables.c
@@ -42,7 +42,8 @@
   hb_set_add (hb_subset_input_drop_tables_set (input), HB_TAG ('h', 'm', 't', 'x'));
   hb_set_destroy (codepoints);
 
-  hb_face_t* subset = hb_subset (face, input);
+  hb_face_t* subset = hb_subset_or_fail (face, input);
+  g_assert (subset);
 
   hb_blob_t *hdmx = hb_face_reference_table (subset, HB_TAG ('h', 'd', 'm', 'x'));
   hb_blob_t *hmtx = hb_face_reference_table (subset, HB_TAG ('h', 'm', 't', 'x'));
diff --git a/test/api/test-subset-glyf.c b/test/api/test-subset-glyf.c
index 3bad4fc..a6a6bbf 100644
--- a/test/api/test-subset-glyf.c
+++ b/test/api/test-subset-glyf.c
@@ -301,11 +301,10 @@
   hb_subset_input_set_flag (input, HB_SUBSET_FLAG_HINTING, false);
   hb_set_destroy (codepoints);
 
-  face_subset = hb_subset_test_create_subset (face, input);
-  g_assert (face_subset);
-  g_assert (face_subset == hb_face_get_empty ());
+  face_subset = hb_subset_or_fail (face, input);
+  g_assert (!face_subset);
 
-  hb_face_destroy (face_subset);
+  hb_subset_input_destroy (input);
   hb_face_destroy (face);
 }
 
diff --git a/test/api/test-subset-hdmx.c b/test/api/test-subset-hdmx.c
index 7178833..c41a121 100644
--- a/test/api/test-subset-hdmx.c
+++ b/test/api/test-subset-hdmx.c
@@ -82,9 +82,8 @@
   hb_set_add (codepoints, 'b');
   hb_set_add (codepoints, 'c');
 
-  subset = hb_subset (face, input);
-  g_assert (subset);
-  g_assert (subset == hb_face_get_empty ());
+  subset = hb_subset_or_fail (face, input);
+  g_assert (!subset);
 
   hb_subset_input_destroy (input);
   hb_face_destroy (subset);
diff --git a/test/api/test-subset-hmtx.c b/test/api/test-subset-hmtx.c
index 1b51dc2..28cca00 100644
--- a/test/api/test-subset-hmtx.c
+++ b/test/api/test-subset-hmtx.c
@@ -162,9 +162,8 @@
   hb_set_add (codepoints, 'b');
   hb_set_add (codepoints, 'c');
 
-  subset = hb_subset (face, input);
-  g_assert (subset);
-  g_assert (subset == hb_face_get_empty ());
+  subset = hb_subset_or_fail (face, input);
+  g_assert (!subset);
 
   hb_subset_input_destroy (input);
   hb_face_destroy (subset);
diff --git a/test/api/test-subset.c b/test/api/test-subset.c
index 85e4fdf..2c35604 100644
--- a/test/api/test-subset.c
+++ b/test/api/test-subset.c
@@ -42,7 +42,7 @@
   hb_set_add (codepoints, 'b');
   hb_set_add (codepoints, 'c');
 
-  subset = hb_subset (face, input);
+  subset = hb_subset_or_fail (face, input);
   g_assert (subset);
   g_assert (subset != hb_face_get_empty ());
 
@@ -64,9 +64,8 @@
   hb_set_add (codepoints, 'b');
   hb_set_add (codepoints, 'c');
 
-  subset = hb_subset (face, input);
-  g_assert (subset);
-  g_assert (subset == hb_face_get_empty ());
+  subset = hb_subset_or_fail (face, input);
+  g_assert (!subset);
 
   hb_subset_input_destroy (input);
   hb_face_destroy (subset);
@@ -86,9 +85,8 @@
   hb_set_add (codepoints, 'b');
   hb_set_add (codepoints, 'c');
 
-  subset = hb_subset (face, input);
-  g_assert (subset);
-  g_assert (subset == hb_face_get_empty ());
+  subset = hb_subset_or_fail (face, input);
+  g_assert (!subset);
 
   hb_subset_input_destroy (input);
   hb_face_destroy (subset);
diff --git a/test/fuzzing/hb-subset-fuzzer.cc b/test/fuzzing/hb-subset-fuzzer.cc
index 692d184..c121301 100644
--- a/test/fuzzing/hb-subset-fuzzer.cc
+++ b/test/fuzzing/hb-subset-fuzzer.cc
@@ -31,7 +31,8 @@
   for (int i = 0; i < text_length; i++)
     hb_set_add (codepoints, text[i]);
 
-  hb_face_t *result = hb_subset (face, input);
+  hb_face_t *result = hb_subset_or_fail (face, input);
+  if (result)
   {
     hb_blob_t *blob = hb_face_reference_blob (result);
     unsigned int length;