diff --git a/src/libespeak-ng/compiledata.c b/src/libespeak-ng/compiledata.c
index 6ab43b0f..250b78b3 100644
--- a/src/libespeak-ng/compiledata.c
+++ b/src/libespeak-ng/compiledata.c
@@ -36,7 +36,6 @@
 #include <espeak-ng/encoding.h>
 
 #include "error.h"
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
@@ -323,9 +322,9 @@ int proc_addr[N_PROCS];
 char proc_names[N_ITEM_STRING+1][N_PROCS];
 
 #define MAX_PROG_BUF 2000
-USHORT *prog_out;
-USHORT *prog_out_max;
-USHORT prog_buf[MAX_PROG_BUF+20];
+unsigned short *prog_out;
+unsigned short *prog_out_max;
+unsigned short prog_buf[MAX_PROG_BUF+20];
 
 static espeak_ng_STATUS ReadPhondataManifest(espeak_ng_ERROR_CONTEXT *context)
 {
@@ -442,8 +441,8 @@ STACK stack[N_STACK];
 #define N_IF_STACK 12
 int if_level;
 typedef struct {
-	USHORT *p_then;
-	USHORT *p_else;
+	unsigned short *p_then;
+	unsigned short *p_else;
 	bool returned;
 } IF_STACK;
 IF_STACK if_stack[N_IF_STACK];
@@ -1626,7 +1625,7 @@ static int CompileIf(int elif)
 	int bitmap;
 	int brackets;
 	bool not_flag;
-	USHORT *prog_last_if = NULL;
+	unsigned short *prog_last_if = NULL;
 
 	then_count = 2;
 	after_if = true;
@@ -1727,7 +1726,7 @@ static int CompileIf(int elif)
 
 static void FillThen(int add)
 {
-	USHORT *p;
+	unsigned short *p;
 	int offset;
 
 	p = if_stack[if_level].p_then;
@@ -1755,8 +1754,8 @@ static void FillThen(int add)
 
 static int CompileElse(void)
 {
-	USHORT *ref;
-	USHORT *p;
+	unsigned short *ref;
+	unsigned short *p;
 
 	if (if_level < 1) {
 		error("ELSE not expected");
@@ -1794,7 +1793,7 @@ static int CompileElif(void)
 
 static int CompileEndif(void)
 {
-	USHORT *p;
+	unsigned short *p;
 	int chain;
 	int offset;
 
@@ -2293,7 +2292,7 @@ static int CompilePhoneme(int compile_phoneme)
 	if (prog_out > prog_buf) {
 		// write out the program for this phoneme
 		fflush(f_phindex);
-		phoneme_out->program = ftell(f_phindex) / sizeof(USHORT);
+		phoneme_out->program = ftell(f_phindex) / sizeof(unsigned short);
 
 		if (f_prog_log != NULL) {
 			phoneme_prog_log.addr = phoneme_out->program;
@@ -2302,8 +2301,8 @@ static int CompilePhoneme(int compile_phoneme)
 		}
 
 		if (compile_phoneme == 0)
-			proc_addr[n_procs++] =  ftell(f_phindex) / sizeof(USHORT);
-		fwrite(prog_buf, sizeof(USHORT), prog_out - prog_buf, f_phindex);
+			proc_addr[n_procs++] =  ftell(f_phindex) / sizeof(unsigned short);
+		fwrite(prog_buf, sizeof(unsigned short), prog_out - prog_buf, f_phindex);
 	}
 
 	return 0;
diff --git a/src/libespeak-ng/compiledict.c b/src/libespeak-ng/compiledict.c
index 4068265e..2a472f49 100644
--- a/src/libespeak-ng/compiledict.c
+++ b/src/libespeak-ng/compiledict.c
@@ -22,6 +22,7 @@
 
 #include <ctype.h>
 #include <errno.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/src/libespeak-ng/dictionary.c b/src/libespeak-ng/dictionary.c
index fb8273bb..5ab68fe4 100644
--- a/src/libespeak-ng/dictionary.c
+++ b/src/libespeak-ng/dictionary.c
@@ -37,6 +37,14 @@
 #include "synthesize.h"
 #include "translate.h"
 
+typedef struct {
+	int points;
+	const char *phonemes;
+	int end_type;
+	char *del_fwd;
+} MatchRecord;
+
+
 int dictionary_skipwords;
 char dictionary_name[40];
 
diff --git a/src/libespeak-ng/error.h b/src/libespeak-ng/error.h
index 7e0dcc9a..103ba619 100644
--- a/src/libespeak-ng/error.h
+++ b/src/libespeak-ng/error.h
@@ -18,6 +18,8 @@
 #ifndef ESPEAK_NG_ERROR_API
 #define ESPEAK_NG_ERROR_API
 
+#include <espeak-ng/espeak_ng.h>
+
 #ifdef __cplusplus
 extern "C"
 {
diff --git a/src/libespeak-ng/espeak_api.c b/src/libespeak-ng/espeak_api.c
index cf0e21af..7e282325 100644
--- a/src/libespeak-ng/espeak_api.c
+++ b/src/libespeak-ng/espeak_api.c
@@ -27,7 +27,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/espeak_command.c b/src/libespeak-ng/espeak_command.c
index 8ccd23da..f5292d6c 100644
--- a/src/libespeak-ng/espeak_command.c
+++ b/src/libespeak-ng/espeak_command.c
@@ -25,7 +25,6 @@
 
 #include <espeak-ng/espeak_ng.h>
 
-#include "speech.h"
 #include "espeak_command.h"
 
 #ifdef USE_ASYNC
diff --git a/src/libespeak-ng/espeak_command.h b/src/libespeak-ng/espeak_command.h
index 8d1d4d23..78204d2a 100644
--- a/src/libespeak-ng/espeak_command.h
+++ b/src/libespeak-ng/espeak_command.h
@@ -16,8 +16,10 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
-#ifndef ESPEAK_COMMAND_H
-#define ESPEAK_COMMAND_H
+#ifndef ESPEAK_NG_COMMAND_H
+#define ESPEAK_NG_COMMAND_H
+
+#include <espeak-ng/espeak_ng.h>
 
 #ifdef __cplusplus
 extern "C"
diff --git a/src/libespeak-ng/event.c b/src/libespeak-ng/event.c
index ce03fa7e..d3789458 100644
--- a/src/libespeak-ng/event.c
+++ b/src/libespeak-ng/event.c
@@ -33,7 +33,6 @@
 #include <espeak-ng/espeak_ng.h>
 #include <espeak-ng/speak_lib.h>
 
-#include "speech.h"
 #include "event.h"
 
 // my_mutex: protects my_thread_is_talking,
diff --git a/src/libespeak-ng/event.h b/src/libespeak-ng/event.h
index abc263b2..5f47e108 100644
--- a/src/libespeak-ng/event.h
+++ b/src/libespeak-ng/event.h
@@ -16,9 +16,6 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
-#ifndef EVENT_H
-#define EVENT_H
-
 /*
    Manage events (sentence, word, mark, end,...), is responsible of calling the external
    callback as soon as the relevant audio sample is played.
@@ -39,6 +36,11 @@
 
  */
 
+#ifndef ESPEAK_NG_EVENT_H
+#define ESPEAK_NG_EVENT_H
+
+#include <espeak-ng/espeak_ng.h>
+
 #ifdef __cplusplus
 extern "C"
 {
diff --git a/src/libespeak-ng/fifo.h b/src/libespeak-ng/fifo.h
index 7d5c001e..ba5e5526 100644
--- a/src/libespeak-ng/fifo.h
+++ b/src/libespeak-ng/fifo.h
@@ -16,12 +16,15 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
-#ifndef FIFO_H
-#define FIFO_H
-
 // Helps to add espeak commands in a first-in first-out queue
 // and run them asynchronously.
 
+#ifndef ESPEAK_NG_FIFO_H
+#define ESPEAK_NG_FIFO_H
+
+#include <espeak-ng/espeak_ng.h>
+#include "espeak_command.h"
+
 #ifdef __cplusplus
 extern "C"
 {
diff --git a/src/libespeak-ng/ieee80.h b/src/libespeak-ng/ieee80.h
index 04ca67f4..df4da90f 100644
--- a/src/libespeak-ng/ieee80.h
+++ b/src/libespeak-ng/ieee80.h
@@ -42,6 +42,7 @@
  * conversions, and accommodated conversions involving +/- infinity,
  * NaN's, and denormalized numbers.
  */
+
 #ifndef IEEE_H
 #define IEEE_H
 
diff --git a/src/libespeak-ng/intonation.c b/src/libespeak-ng/intonation.c
index 8384584a..0cd19bc2 100644
--- a/src/libespeak-ng/intonation.c
+++ b/src/libespeak-ng/intonation.c
@@ -28,7 +28,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/klatt.c b/src/libespeak-ng/klatt.c
index 8b754307..99a82526 100644
--- a/src/libespeak-ng/klatt.c
+++ b/src/libespeak-ng/klatt.c
@@ -34,7 +34,6 @@
 #include <espeak-ng/espeak_ng.h>
 #include <espeak-ng/speak_lib.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
@@ -938,7 +937,7 @@ static int Wavegen_Klatt(int resume)
 static void SetSynth_Klatt(int length, frame_t *fr1, frame_t *fr2, voice_t *v, int control)
 {
 	int ix;
-	DOUBLEX next;
+	double next;
 	int qix;
 	int cmd;
 	frame_t *fr3;
diff --git a/src/libespeak-ng/klatt.h b/src/libespeak-ng/klatt.h
index 23934ad5..f8acdb84 100644
--- a/src/libespeak-ng/klatt.h
+++ b/src/libespeak-ng/klatt.h
@@ -21,6 +21,12 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
+#ifndef ESPEAK_NG_KLATT_H
+#define ESPEAK_NG_KLATT_H
+
+#include "speech.h"
+#include "synthesize.h"
+
 #ifdef __cplusplus
 extern "C"
 {
@@ -161,14 +167,14 @@ typedef struct {
 	int bw;   // klatt bandwidth
 	int ap;   // parallel amplitude
 	int bp;   // parallel bandwidth
-	DOUBLEX freq1; // floating point versions of the above
-	DOUBLEX bw1;
-	DOUBLEX ap1;
-	DOUBLEX bp1;
-	DOUBLEX freq_inc;    // increment by this every 64 samples
-	DOUBLEX bw_inc;
-	DOUBLEX ap_inc;
-	DOUBLEX bp_inc;
+	double freq1; // floating point versions of the above
+	double bw1;
+	double ap1;
+	double bp1;
+	double freq_inc;    // increment by this every 64 samples
+	double bw_inc;
+	double ap_inc;
+	double bp_inc;
 }  klatt_peaks_t;
 
 void KlattInit(void);
@@ -179,3 +185,5 @@ int Wavegen_Klatt2(int length, int resume, frame_t *fr1, frame_t *fr2);
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/mbrowrap.c b/src/libespeak-ng/mbrowrap.c
index e9abde41..71d6bb19 100644
--- a/src/libespeak-ng/mbrowrap.c
+++ b/src/libespeak-ng/mbrowrap.c
@@ -82,7 +82,6 @@ void unload_MBR()
 #include <unistd.h>
 
 #include <espeak-ng/espeak_ng.h>
-#include "speech.h"
 
 /*
  * mbrola instance parameters
diff --git a/src/libespeak-ng/numbers.c b/src/libespeak-ng/numbers.c
index 25db8f24..8c9ad205 100644
--- a/src/libespeak-ng/numbers.c
+++ b/src/libespeak-ng/numbers.c
@@ -31,7 +31,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/phoneme.h b/src/libespeak-ng/phoneme.h
index 0f18ef80..fd070763 100644
--- a/src/libespeak-ng/phoneme.h
+++ b/src/libespeak-ng/phoneme.h
@@ -17,6 +17,11 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
+#ifndef ESPEAK_NG_PHONEME_H
+#define ESPEAK_NG_PHONEME_H
+
+#include <espeak-ng/espeak_ng.h>
+
 #ifdef __cplusplus
 extern "C"
 {
@@ -291,3 +296,5 @@ extern int phoneme_tab_number;
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/phonemelist.c b/src/libespeak-ng/phonemelist.c
index 3d8d3e23..60ced1d1 100644
--- a/src/libespeak-ng/phonemelist.c
+++ b/src/libespeak-ng/phonemelist.c
@@ -29,7 +29,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/setlengths.c b/src/libespeak-ng/setlengths.c
index bf879f63..831e2f51 100644
--- a/src/libespeak-ng/setlengths.c
+++ b/src/libespeak-ng/setlengths.c
@@ -28,7 +28,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/sintab.h b/src/libespeak-ng/sintab.h
index 4a84d12d..628a81d3 100644
--- a/src/libespeak-ng/sintab.h
+++ b/src/libespeak-ng/sintab.h
@@ -17,6 +17,9 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
+#ifndef ESPEAK_NG_SINTAB_H
+#define ESPEAK_NG_SINTAB_H
+
 #ifdef __cplusplus
 extern "C"
 {
@@ -284,3 +287,5 @@ short int sin_tab[2048] = {
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/spect.c b/src/libespeak-ng/spect.c
index e468dfd6..dc027df5 100644
--- a/src/libespeak-ng/spect.c
+++ b/src/libespeak-ng/spect.c
@@ -30,7 +30,6 @@
 #include <espeak-ng/espeak_ng.h>
 #include <espeak-ng/speak_lib.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
@@ -193,7 +192,7 @@ static espeak_ng_STATUS LoadFrame(SpectFrame *frame, FILE *stream, int file_form
 		}
 	}
 
-	spect_data = malloc(sizeof(USHORT) * frame->nx);
+	spect_data = malloc(sizeof(unsigned short) * frame->nx);
 
 	if (spect_data == NULL)
 		return ENOMEM;
diff --git a/src/libespeak-ng/spect.h b/src/libespeak-ng/spect.h
index f4f1c883..d04b206b 100644
--- a/src/libespeak-ng/spect.h
+++ b/src/libespeak-ng/spect.h
@@ -17,6 +17,13 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
+#ifndef ESPEAK_NG_SPECT_H
+#define ESPEAK_NG_SPECT_H
+
+#include <espeak-ng/espeak_ng.h>
+#include "synthesize.h"
+#include "speech.h"
+
 #ifdef __cplusplus
 extern "C"
 {
@@ -98,7 +105,7 @@ typedef struct {
 	unsigned short nx;
 	short markers;
 	int max_y;
-	USHORT *spect; // sqrt of harmonic amplitudes,  1-nx at 'pitch'
+	unsigned short *spect; // sqrt of harmonic amplitudes,  1-nx at 'pitch'
 
 	short klatt_param[N_KLATTP2];
 
@@ -133,3 +140,5 @@ espeak_ng_STATUS LoadSpectSeq(SpectSeq *spect, const char *filename);
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/speech.h b/src/libespeak-ng/speech.h
index 6f703b87..fd3d3e75 100644
--- a/src/libespeak-ng/speech.h
+++ b/src/libespeak-ng/speech.h
@@ -17,8 +17,10 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
-#ifndef SPEECH_H
-#define SPEECH_H
+#ifndef ESPEAK_NG_SPEECH_H
+#define ESPEAK_NG_SPEECH_H
+
+#include <espeak-ng/espeak_ng.h>
 
 #ifdef __cplusplus
 extern "C"
@@ -55,10 +57,6 @@ extern "C"
    #define PATH_ESPEAK_DATA  "/usr/share/espeak-ng-data"
 #endif
 
-typedef unsigned short USHORT;
-typedef unsigned char UCHAR;
-typedef double DOUBLEX;
-
 typedef struct {
 	const char *mnem;
 	int value;
diff --git a/src/libespeak-ng/ssml.h b/src/libespeak-ng/ssml.h
index 5399542a..f47f213c 100644
--- a/src/libespeak-ng/ssml.h
+++ b/src/libespeak-ng/ssml.h
@@ -21,6 +21,11 @@
 #ifndef ESPEAK_NG_SSML_API
 #define ESPEAK_NG_SSML_API
 
+#include <stdbool.h>
+#include <wchar.h>
+
+#include <espeak-ng/speak_lib.h>
+
 #ifdef __cplusplus
 extern "C"
 {
diff --git a/src/libespeak-ng/synthdata.c b/src/libespeak-ng/synthdata.c
index 09d1def6..81ce99d4 100644
--- a/src/libespeak-ng/synthdata.c
+++ b/src/libespeak-ng/synthdata.c
@@ -47,7 +47,7 @@ int current_phoneme_table;
 PHONEME_TAB *phoneme_tab[N_PHONEME_TAB];
 unsigned char phoneme_tab_flags[N_PHONEME_TAB];   // bit 0: not inherited
 
-USHORT *phoneme_index = NULL;
+unsigned short *phoneme_index = NULL;
 char *phondata_ptr = NULL;
 unsigned char *wavefile_data = NULL;
 static unsigned char *phoneme_tab_data = NULL;
@@ -498,7 +498,7 @@ static int CountVowelPosition(PHONEME_LIST *plist)
 	return count;
 }
 
-static bool InterpretCondition(Translator *tr, int control, PHONEME_LIST *plist, USHORT *p_prog, WORD_PH_DATA *worddata)
+static bool InterpretCondition(Translator *tr, int control, PHONEME_LIST *plist, unsigned short *p_prog, WORD_PH_DATA *worddata)
 {
 	int which;
 	int ix;
@@ -693,9 +693,9 @@ static bool InterpretCondition(Translator *tr, int control, PHONEME_LIST *plist,
 	return false;
 }
 
-static void SwitchOnVowelType(PHONEME_LIST *plist, PHONEME_DATA *phdata, USHORT **p_prog, int instn_type)
+static void SwitchOnVowelType(PHONEME_LIST *plist, PHONEME_DATA *phdata, unsigned short **p_prog, int instn_type)
 {
-	USHORT *prog;
+	unsigned short *prog;
 	int voweltype;
 	signed char x;
 
@@ -716,7 +716,7 @@ static void SwitchOnVowelType(PHONEME_LIST *plist, PHONEME_DATA *phdata, USHORT
 	*p_prog += 12;
 }
 
-int NumInstnWords(USHORT *prog)
+int NumInstnWords(unsigned short *prog)
 {
 	int instn;
 	int instn2;
@@ -769,8 +769,8 @@ void InterpretPhoneme(Translator *tr, int control, PHONEME_LIST *plist, PHONEME_
 	// bit 8:  change phonemes
 
 	PHONEME_TAB *ph;
-	USHORT *prog;
-	USHORT instn;
+	unsigned short *prog;
+	unsigned short instn;
 	int instn2;
 	int or_flag;
 	bool truth;
@@ -782,7 +782,7 @@ void InterpretPhoneme(Translator *tr, int control, PHONEME_LIST *plist, PHONEME_
 
 	#define N_RETURN 10
 	int n_return = 0;
-	USHORT *return_addr[N_RETURN]; // return address stack
+	unsigned short *return_addr[N_RETURN]; // return address stack
 
 	ph = plist->ph;
 
diff --git a/src/libespeak-ng/synthesize.c b/src/libespeak-ng/synthesize.c
index 0ce0dfa2..194d5343 100644
--- a/src/libespeak-ng/synthesize.c
+++ b/src/libespeak-ng/synthesize.c
@@ -32,7 +32,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/synthesize.h b/src/libespeak-ng/synthesize.h
index 826b237f..d5b3a50b 100644
--- a/src/libespeak-ng/synthesize.h
+++ b/src/libespeak-ng/synthesize.h
@@ -17,13 +17,20 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
-#include <stdbool.h>
+#ifndef ESPEAK_NG_SYNTHESIZE_H
+#define ESPEAK_NG_SYNTHESIZE_H
 
 #ifdef __cplusplus
 extern "C"
 {
 #endif
 
+#include <stdint.h>
+#include <stdbool.h>
+#include <espeak-ng/espeak_ng.h>
+#include "phoneme.h"
+#include "voice.h"
+
 #define espeakINITIALIZE_PHONEME_IPA 0x0002 // move this to speak_lib.h, after eSpeak version 1.46.02
 
 #define N_PHONEME_LIST 1000 // enough for source[N_TR_SOURCE] full of text, else it will truncate
@@ -128,14 +135,14 @@ typedef struct {
 	int height;   // height<<15
 	int left;     // Hz<<16
 	int right;    // Hz<<16
-	DOUBLEX freq1; // floating point versions of the above
-	DOUBLEX height1;
-	DOUBLEX left1;
-	DOUBLEX right1;
-	DOUBLEX freq_inc; // increment by this every 64 samples
-	DOUBLEX height_inc;
-	DOUBLEX left_inc;
-	DOUBLEX right_inc;
+	double freq1; // floating point versions of the above
+	double height1;
+	double left1;
+	double right1;
+	double freq_inc; // increment by this every 64 samples
+	double height_inc;
+	double left_inc;
+	double right_inc;
 } wavegen_peaks_t;
 
 typedef struct {
@@ -552,10 +559,12 @@ int DoSpect2(PHONEME_TAB *this_ph, int which, FMT_PARAMS *fmt_params,  PHONEME_L
 int PauseLength(int pause, int control);
 int LookupPhonemeTable(const char *name);
 unsigned char *GetEnvelope(int index);
-int NumInstnWords(USHORT *prog);
+int NumInstnWords(unsigned short *prog);
 
 void InitBreath(void);
 
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/tr_languages.c b/src/libespeak-ng/tr_languages.c
index 364614e9..2886f16a 100644
--- a/src/libespeak-ng/tr_languages.c
+++ b/src/libespeak-ng/tr_languages.c
@@ -30,7 +30,6 @@
 #include <espeak-ng/speak_lib.h>
 #include <espeak-ng/encoding.h>
 
-#include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
 #include "synthesize.h"
diff --git a/src/libespeak-ng/translate.h b/src/libespeak-ng/translate.h
index 2016b2d5..e5e2b2cb 100644
--- a/src/libespeak-ng/translate.h
+++ b/src/libespeak-ng/translate.h
@@ -17,6 +17,16 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
+#ifndef ESPEAK_NG_TRANSLATE_H
+#define ESPEAK_NG_TRANSLATE_H
+
+#include <stdbool.h>
+
+#include <espeak-ng/espeak_ng.h>
+#include <espeak-ng/encoding.h>
+
+#include "synthesize.h"
+
 #ifdef __cplusplus
 extern "C"
 {
@@ -257,13 +267,6 @@ int clause_type_from_codepoint(uint32_t c);
 
 typedef const char *constcharptr;
 
-typedef struct {
-	int points;
-	const char *phonemes;
-	int end_type;
-	char *del_fwd;
-} MatchRecord;
-
 // used to mark words with the source[] buffer
 typedef struct {
 	unsigned int flags;
@@ -579,16 +582,6 @@ typedef struct {
 	int suffix_add_e;      // replace a suffix (which has the SUFX_E flag) with this character
 } LANGUAGE_OPTIONS;
 
-// a parameter of ChangePhonemes()
-typedef struct {
-	int flags;
-	unsigned char stress;          // stress level of this vowel
-	unsigned char stress_highest;  // the highest stress level of a vowel in this word
-	unsigned char n_vowels;        // number of vowels in the word
-	unsigned char vowel_this;      // syllable number of this vowel (counting from 1)
-	unsigned char vowel_stressed;  // syllable number of the highest stressed vowel
-} CHANGEPH;
-
 typedef struct {
 	LANGUAGE_OPTIONS langopts;
 	int translator_name;
@@ -759,7 +752,6 @@ void print_dictionary_flags(unsigned int *flags, char *buf, int buf_len);
 char *DecodeRule(const char *group_chars, int group_length, char *rule, int control);
 
 void MakePhonemeList(Translator *tr, int post_pause, bool new_sentence);
-int ChangePhonemes_ru(Translator *tr, PHONEME_LIST2 *phlist, int n_ph, int index, PHONEME_TAB *ph, CHANGEPH *ch);
 void ApplySpecialAttribute2(Translator *tr, char *phonemes, int dict_flags);
 void AppendPhonemes(Translator *tr, char *string, int size, const char *ph);
 
@@ -784,3 +776,5 @@ extern FILE *f_trans; // for logging
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/voice.h b/src/libespeak-ng/voice.h
index ff7d7a79..d33c8ca7 100644
--- a/src/libespeak-ng/voice.h
+++ b/src/libespeak-ng/voice.h
@@ -17,6 +17,11 @@
  * along with this program; if not, see: <http://www.gnu.org/licenses/>.
  */
 
+#ifndef ESPEAK_NG_VOICE_H
+#define ESPEAK_NG_VOICE_H
+
+#include <espeak-ng/espeak_ng.h>
+
 #ifdef __cplusplus
 extern "C"
 {
@@ -73,7 +78,7 @@ typedef struct {
 } voice_t;
 
 // percentages shown to user, ix=N_PEAKS means ALL peaks
-extern USHORT voice_pcnt[N_PEAKS+1][3];
+extern unsigned short voice_pcnt[N_PEAKS+1][3];
 
 extern espeak_VOICE current_voice_selected;
 
@@ -93,3 +98,5 @@ void FreeVoiceList(void);
 #ifdef __cplusplus
 }
 #endif
+
+#endif
diff --git a/src/libespeak-ng/wavegen.c b/src/libespeak-ng/wavegen.c
index 027a8d22..ab833cf8 100644
--- a/src/libespeak-ng/wavegen.c
+++ b/src/libespeak-ng/wavegen.c
@@ -32,10 +32,10 @@
 #include <espeak-ng/espeak_ng.h>
 #include <espeak-ng/speak_lib.h>
 
+#include "synthesize.h"
 #include "speech.h"
 #include "phoneme.h"
 #include "voice.h"
-#include "synthesize.h"
 
 #ifdef INCLUDE_KLATT
 #include "klatt.h"
@@ -1151,7 +1151,7 @@ static void SetSynth(int length, int modn, frame_t *fr1, frame_t *fr2, voice_t *
 		return;
 
 	int ix;
-	DOUBLEX next;
+	double next;
 	int length2;
 	int length4;
 	int qix;