diff --git a/src/espeakedit.cpp b/src/espeakedit.cpp
index feb7b749..b7c0c900 100644
--- a/src/espeakedit.cpp
+++ b/src/espeakedit.cpp
@@ -41,9 +41,6 @@ static const char *about_string = "<font size=0><b>espeakedit </b> %s<br>Author:
 "<a href=\"http://espeak.sourceforge.net/\">http://espeak.sourceforge.net</a><br>"
 "Licensed under <a href=\"http://espeak.sourceforge.net/license.html\">GNU General Public License version 3</a></font>";
 
-extern "C" void CompilePhonemeData(long rate, FILE *log);
-extern "C" espeak_ng_STATUS CompileIntonation(FILE *log);
-
 int progress_max;
 int gui_flag = 0;
 
@@ -121,8 +118,8 @@ else
 			fprintf(stderr, "Failed to load default voice\n");
 			exit(1);
 		}
-		CompilePhonemeData(22050, stderr);
-		CompileIntonation(stderr);
+		espeak_ng_CompilePhonemeData(22050, stderr);
+		espeak_ng_CompileIntonation(stderr);
 	}
     exit(0);
 }
diff --git a/src/include/espeak-ng/espeak_ng.h b/src/include/espeak-ng/espeak_ng.h
index 9b54eaa4..dd74f5ec 100644
--- a/src/include/espeak-ng/espeak_ng.h
+++ b/src/include/espeak-ng/espeak_ng.h
@@ -48,6 +48,12 @@ typedef enum {
 ESPEAK_NG_API espeak_ng_STATUS
 espeak_ng_CompileMbrolaVoice(const char *path, FILE *log);
 
+ESPEAK_NG_API espeak_ng_STATUS
+espeak_ng_CompilePhonemeData(long rate, FILE *log);
+
+ESPEAK_NG_API espeak_ng_STATUS
+espeak_ng_CompileIntonation(FILE *log);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/libespeak-ng/compiledata.c b/src/libespeak-ng/compiledata.c
index 7785b681..dcf3f9ad 100644
--- a/src/libespeak-ng/compiledata.c
+++ b/src/libespeak-ng/compiledata.c
@@ -3392,7 +3392,7 @@ static void CompilePhonemeFiles()
 
 
 
-static void CompilePhonemeData2(const char *source, FILE *log)
+static espeak_ng_STATUS CompilePhonemeData2(const char *source, FILE *log)
 {//================================================
 	char fname[sizeof(path_home)+40];
 	sprintf(fname,"%s/../phsource",path_home);
@@ -3412,7 +3412,7 @@ make_envs();
 	if(!access(fname, 755))
 	{
 		fprintf(log,"Can't find phoneme source directory: %s\n",fname);
-		return;
+		return ENE_READ_ERROR;
 	}
 
 	strncpy0(current_fname,source,sizeof(current_fname));
@@ -3422,7 +3422,7 @@ make_envs();
 	if(f_in == NULL)
 	{
 		fprintf(log,"Can't read master phonemes file: %s\n",fname);
-		return;
+		return ENE_READ_ERROR;
 	}
 
 	sprintf(fname,"%s/../phsource/%s",path_home,"error_log");
@@ -3468,7 +3468,7 @@ make_envs();
 
 	if(f_phdata==NULL || f_phindex==NULL || f_phtab==NULL)
 	{
-		return;
+		return ENE_WRITE_ERROR;
 	}
 
 	sprintf(fname,"%s/../phsource/compile_prog_log",path_home);
@@ -3521,6 +3521,7 @@ fprintf(f_errors,"\nRefs %d,  Reused %d\n",count_references,duplicate_references
         fclose(f_errors);
 
     ReadPhondataManifest();
+    return ENS_OK;
 }  // end of CompilePhonemeData
 
 
@@ -3569,7 +3570,9 @@ int LookupEnvelopeName(const char *name)
 }
 
 
-espeak_ng_STATUS CompileIntonation(FILE *log)
+#pragma GCC visibility push(default)
+
+espeak_ng_STATUS espeak_ng_CompileIntonation(FILE *log)
 {//=====================
 	int ix;
 	char *p;
@@ -3870,9 +3873,11 @@ espeak_ng_STATUS CompileIntonation(FILE *log)
 
 
 
-void CompilePhonemeData(long rate, FILE *log)
+espeak_ng_STATUS espeak_ng_CompilePhonemeData(long rate, FILE *log)
 {
     WavegenInit(rate, 0);
 	WavegenSetVoice(voice);
-	CompilePhonemeData2("phonemes", log);
+	return CompilePhonemeData2("phonemes", log);
 }
+
+#pragma GCC visibility pop