diff --git a/src/libespeak-ng/compiledata.c b/src/libespeak-ng/compiledata.c
index 775242d6..41722cb1 100644
--- a/src/libespeak-ng/compiledata.c
+++ b/src/libespeak-ng/compiledata.c
@@ -2016,7 +2016,9 @@ int CompilePhoneme(int compile_phoneme)
 				error("Missing 'endphoneme' before end-of-file"); // end of file
 				break;
 			}
-			if (phoneme_add_feature(phoneme_out, item_string, NULL) == ENS_OK)
+
+			phoneme_feature_t feature = phoneme_feature_from_string(item_string);
+			if (phoneme_add_feature(phoneme_out, feature) == ENS_OK)
 				continue;
 			error("Bad keyword in phoneme definition '%s'", item_string);
 			continue;
diff --git a/src/libespeak-ng/error.c b/src/libespeak-ng/error.c
index d96a7f3a..c1c5ceb6 100644
--- a/src/libespeak-ng/error.c
+++ b/src/libespeak-ng/error.c
@@ -74,27 +74,6 @@ create_version_mismatch_error_context(espeak_ng_ERROR_CONTEXT *context,
 	return ENS_VERSION_MISMATCH;
 }
 
-espeak_ng_STATUS
-create_name_error_context(espeak_ng_ERROR_CONTEXT *context,
-                          espeak_ng_STATUS status,
-                          const char *name)
-{
-	if (context) {
-		if (*context) {
-			free((*context)->name);
-		} else {
-			*context = malloc(sizeof(espeak_ng_ERROR_CONTEXT_));
-			if (!*context)
-				return ENOMEM;
-		}
-		(*context)->type = ERROR_CONTEXT_NAME;
-		(*context)->name = strdup(name);
-		(*context)->version = 0;
-		(*context)->expected_version = 0;
-	}
-	return status;
-}
-
 #pragma GCC visibility push(default)
 
 ESPEAK_NG_API void
@@ -182,9 +161,6 @@ espeak_ng_PrintStatusCodeMessage(espeak_ng_STATUS status,
 			fprintf(out, "Error: %s at '%s' (expected 0x%x, got 0x%x).\n",
 			        error, context->name, context->expected_version, context->version);
 			break;
-		case ERROR_CONTEXT_NAME:
-			fprintf(out, "Error: %s (got \"%s\").\n", error, context->name);
-			break;
 		}
 	} else
 		fprintf(out, "Error: %s.\n", error);
diff --git a/src/libespeak-ng/error.h b/src/libespeak-ng/error.h
index c3b3fd30..7e0dcc9a 100644
--- a/src/libespeak-ng/error.h
+++ b/src/libespeak-ng/error.h
@@ -27,7 +27,6 @@ typedef enum
 {
 	ERROR_CONTEXT_FILE,
 	ERROR_CONTEXT_VERSION,
-	ERROR_CONTEXT_NAME,
 } espeak_ng_CONTEXT_TYPE;
 
 typedef struct espeak_ng_ERROR_CONTEXT_
@@ -49,11 +48,6 @@ create_version_mismatch_error_context(espeak_ng_ERROR_CONTEXT *context,
                                       int version,
                                       int expected_version);
 
-espeak_ng_STATUS
-create_name_error_context(espeak_ng_ERROR_CONTEXT *context,
-                          espeak_ng_STATUS status,
-                          const char *name);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/libespeak-ng/phoneme.c b/src/libespeak-ng/phoneme.c
index 0af4a71a..2adaba70 100644
--- a/src/libespeak-ng/phoneme.c
+++ b/src/libespeak-ng/phoneme.c
@@ -25,22 +25,20 @@
 #include <espeak-ng/speak_lib.h>
 
 #include "phoneme.h"
-#include "error.h"
 
-uint32_t lookup_feature(const char *feature) {
-	if (strlen(feature) != 3)
+phoneme_feature_t phoneme_feature_from_string(const char *feature)
+{
+	if (!feature || strlen(feature) != 3)
 		return inv;
 	return (feature[0] << 16) | (feature[1] << 8) | feature[2];
 }
 
 espeak_ng_STATUS
 phoneme_add_feature(PHONEME_TAB *phoneme,
-                    const char *feature,
-                    espeak_ng_ERROR_CONTEXT *context)
+                    phoneme_feature_t feature)
 {
-	if (!phoneme || !feature) return EINVAL;
-
-	switch (lookup_feature(feature))
+	if (!phoneme) return EINVAL;
+	switch (feature)
 	{
 	// manner of articulation
 	case nas:
@@ -220,7 +218,7 @@ phoneme_add_feature(PHONEME_TAB *phoneme,
 		break;
 	// invalid phoneme feature
 	default:
-		return create_name_error_context(context, ENS_UNKNOWN_PHONEME_FEATURE, feature);
+		return ENS_UNKNOWN_PHONEME_FEATURE;
 	}
 	return ENS_OK;
 }
diff --git a/src/libespeak-ng/phoneme.h b/src/libespeak-ng/phoneme.h
index 16137a04..cef848f7 100644
--- a/src/libespeak-ng/phoneme.h
+++ b/src/libespeak-ng/phoneme.h
@@ -23,7 +23,7 @@ extern "C"
 #endif
 
 // See docs/phonemes.md for the list of supported features.
-enum feature_t {
+typedef enum {
 #	define FEATURE_T(a, b, c) ((a << 16) | (b << 8) | (c))
 	// invalid phoneme feature name
 	inv = 0,
@@ -114,7 +114,9 @@ enum feature_t {
 	fts = FEATURE_T('f', 't', 's'),
 	lns = FEATURE_T('l', 'n', 's'),
 #	undef FEATURE_T
-};
+} phoneme_feature_t;
+
+phoneme_feature_t phoneme_feature_from_string(const char *feature);
 
 // phoneme types
 #define phPAUSE   0
@@ -207,8 +209,7 @@ typedef struct {
 
 espeak_ng_STATUS
 phoneme_add_feature(PHONEME_TAB *phoneme,
-                    const char *feature,
-                    espeak_ng_ERROR_CONTEXT *context);
+                    phoneme_feature_t feature);
 
 // Several phoneme tables may be loaded into memory. phoneme_tab points to
 // one for the current voice