DecompilePhoneme does nothing (returns before doing anything), so remove it (it was used to debug/trace CompilePhoneme).

src/libespeak-ng/compiledata.c

 	return NULL;
 }
 
-static void DecompilePhoneme(FILE *f_out, PHONEME_TAB *ph, int compile_phoneme)
-{
-	USHORT *pc;
-	int instn;
-	int instn_category;
-	int address, address2;
-	int data1;
-	int type2;
-	int ix;
-	int any;
-	const char *name;
-	char buf[120];
-
-	static const char *instn_category_string[16] = {
-		"", "", "IF", "IF OR",
-		"", "", "", "",
-		"", "", "", "FMT",
-		"WAV", "NextVowelStart", "PrevVowelEnd", "+wav"
-	};
-
-	static const char *nextPh_string[6] = {
-		"prevPh", "thisPh", "nextPh", "next2Ph", "nextPhW", "**",
-	};
-
-	static const char *instn0_string[] = {
-		"invalid", "RETURN", "Continue", "DeleteNextPhoneme",
-	};
-
-	static const char *instn10_string[] = {
-		"", "VowelIn", "VowelOut", "Tone", "",
-	};
-
-	static const char *instn_jumps[] = {
-		"JMP", "Invalid", "Invalid", "Invalid",
-		"JMP false", "SwitchNextVowelType", "SwitchPrevVowelType", "Invalid"
-	};
-
-	static char instn1_paramtype[] = {
-		0, 3, 3, 3, 3, 3, 3, 1,
-		1, 1, 1, 1, 1, 0, 0, 0,
-		3, 3, 3, 3, 3, 3, 3, 3,
-		0, 0, 0, 0, 0, 0, 0, 0
-	};
-
-	return;
-
-	if (compile_phoneme)
-		fprintf(f_out, "\nPhoneme %s (%d)\n", WordToString(ph->mnemonic), ph->code);
-	else
-		fprintf(f_out, "\nProcedure %s\n", proc_names[n_procs]);
-
-	pc = prog_buf;
-	while (pc < prog_out) {
-		instn = *pc++;
-		instn_category = (instn >> 12) & 0xf;
-		data1 = instn & 0xff;
-		type2 = (instn >> 8) & 0xf;
-		fprintf(f_out, "  %.3x: %.4x  %s", (unsigned int)(pc-prog_buf), instn, instn_category_string[instn_category]);
-
-		switch (instn_category)
-		{
-		case 0:
-		case 1:
-			type2 = instn >> 8;
-
-			if (instn < 0x100) {
-				if (data1 > 2)
-					data1 = 0;
-				fprintf(f_out, "%s", instn0_string[data1]);
-			} else if (type2 == i_IPA_NAME) {
-				for (ix = 0; ix < data1; ix += 2) {
-					instn = *pc++;
-					buf[ix] = instn >> 8;
-					buf[ix+1] = instn & 0xff;
-				}
-				buf[ix] = 0;
-				fprintf(f_out, "ipa %s", buf);
-			} else {
-				fprintf(f_out, "%s(", KeyToMnem(keywords, tINSTRN1, type2));
-				switch (instn1_paramtype[type2])
-				{
-				case 0:
-					fprintf(f_out, "%.4x", instn);
-					break;
-				case 1:
-					fprintf(f_out, "%d", data1);
-					break;
-				case 3:
-					fprintf(f_out, "%s", WordToString(phoneme_tab2[data1].mnemonic));
-					break;
-				}
-				fprintf(f_out, ")");
-			}
-			break;
-		case 2:
-		case 3:
-			if (type2 < 12) {
-				fprintf(f_out, " %s(", nextPh_string[type2 % 6]);
-				if (type2 >= 6) {
-					switch (data1 >> 5)
-					{
-					case 0:
-						name = KeyToMnem(keywords, tPHONEME_TYPE, (data1 & 0x1f));
-						if (name != NULL)
-							fprintf(f_out, "is%s", name);
-						else
-							fprintf(f_out, "%d %d", (data1 >> 5), (data1 & 0x1f));
-						break;
-					case 1:
-						fprintf(f_out, "%d %d", (data1 >> 5), (data1 & 0x1f));
-						break;
-					case 2:
-						fprintf(f_out, "%d %d", (data1 >> 5), (data1 & 0x1f));
-						break;
-					case 4:
-						name = KeyToMnem(k_properties, -1, 0x80+(data1 & 0x1f));
-						if (name != NULL)
-							fprintf(f_out, "%s", name);
-						else
-							fprintf(f_out, "%d %d", (data1 >> 5), (data1 & 0x1f));
-						break;
-					default:
-						fprintf(f_out, "%d %d", (data1 >> 5), (data1 & 0x1f));
-						break;
-					}
-				} else {
-					fprintf(f_out, "%s", WordToString(phoneme_tab2[data1].mnemonic));
-				}
-			} else if (type2 == 8) {
-				// list of numbers
-				fprintf(f_out, " StressLevel(");
-				any = 0;
-				for (ix = 0; ix < 8; ix++) {
-					if (data1 & (1 << ix)) {
-						if (any)
-							fputc(',', f_out);
-						any = 1;
-						fprintf(f_out, "%d", ix);
-					}
-				}
-			} else {
-				name = KeyToMnem(k_conditions, tTEST, instn & 0xfff);
-				fprintf(f_out, "%s(", name);
-			}
-			fprintf(f_out, ")");
-			break;
-		case 6:
-			fprintf(f_out, "%s", instn_jumps[(instn >> 9) & 7]);
-			fprintf(f_out, " %d", instn & 0x1ff);
-			break;
-		case 9:
-			address = ((data1 & 0xf) << 4) + *pc++;
-			fprintf(f_out, "CALL %.5x", address);
-			break;
-		case 10:
-			fprintf(f_out, "%s", instn10_string[type2]);
-			switch (type2)
-			{
-			case 1:
-			case 2:
-				address = (data1 << 16) + pc[0];
-				address2 = (pc[1] << 16) + pc[2];
-				pc += 3;
-				fprintf(f_out, " %.6x %.8x", address, address2);
-				break;
-			case 3:
-				address = ((instn & 0xf) << 16) + *pc++;
-				address2 = ((instn & 0xf0) << 12) + *pc++;
-				fprintf(f_out, " %.5x %.5x", address, address2);
-				break;
-			}
-			break;
-		case 11:
-		case 12:
-		case 13:
-		case 14:
-		case 15:
-			address = ((instn & 0xf) << 16) + *pc++;
-			fprintf(f_out, " %d %.5x", (instn >> 4) & 0xff, address*4);
-			break;
-		}
-		fprintf(f_out, "\n");
-	}
-}
-
 static int n_phoneme_tabs;
 static int n_phcodes;
 
 			phoneme_out->mnemonic = 0x01; // will not be recognised
 	}
 
-	DecompilePhoneme(f_errors, phoneme_out, compile_phoneme);
-
 	if (prog_out > prog_buf) {
 		// write out the program for this phoneme
 		fflush(f_phindex);