tests: Fix -Wmissing-prototypes warnings.

configure.ac

 dnl Reference: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
 dnl ================================================================
 
+AX_CHECK_COMPILE_FLAG([-Wmissing-prototypes],    [CFLAGS="-Wmissing-prototypes $CFLAGS"])
 AX_CHECK_COMPILE_FLAG([-Wreturn-type],           [CFLAGS="-Wreturn-type $CFLAGS"])
 AX_CHECK_COMPILE_FLAG([-Wunused],                [CFLAGS="-Wunused $CFLAGS"])
 AX_CHECK_COMPILE_FLAG([-Wunused-parameter],      [CFLAGS="-Wunused-parameter $CFLAGS"])

tests/api.c

 
 // region espeak_Initialize
 
-void
+static void
 test_espeak_terminate_without_initialize()
 {
 	printf("testing espeak_Terminate without espeak_Initialize\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_initialize()
 {
 	printf("testing espeak_Initialize\n");
 // endregion
 // region espeak_Synth
 
-void
+static void
 test_espeak_synth()
 {
 	printf("testing espeak_Synth\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_synth_no_voices(const char *path)
 {
 	printf("testing espeak_Synth in path with no voices\n");
 // endregion
 // region espeak_ng_Synthesize
 
-void
+static void
 test_espeak_ng_synthesize()
 {
 	printf("testing espeak_ng_Synthesize\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_ng_synthesize_no_voices(const char *path)
 {
 	printf("testing espeak_ng_Synthesize in path with no voices\n");
 // endregion
 // region espeak_SetVoiceByName
 
-void
+static void
 test_espeak_set_voice_by_name_null_voice()
 {
 	printf("testing espeak_SetVoiceByName(NULL)\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_name_blank_voice()
 {
 	printf("testing espeak_SetVoiceByName(\"\")\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_name_valid_voice()
 {
 	printf("testing espeak_SetVoiceByName(\"de\")\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_name_invalid_voice()
 {
 	printf("testing espeak_SetVoiceByName(\"zzz\")\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_name_language_variant_intonation_parameter()
 {
 	printf("testing espeak_SetVoiceByName(\"!v/Annie\") (language variant; intonation)\n");
 // endregion
 // region espeak_SetVoiceByProperties
 
-void
+static void
 test_espeak_set_voice_by_properties_empty()
 {
 	printf("testing espeak_SetVoiceByProperties: (none)\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_properties_blank_language()
 {
 	printf("testing espeak_SetVoiceByProperties: languages=\"\"\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_properties_with_valid_language()
 {
 	printf("testing espeak_SetVoiceByProperties: languages=\"mk\" (valid)\n");
 	assert(p_decoder == NULL);
 }
 
-void
+static void
 test_espeak_set_voice_by_properties_with_invalid_language()
 {
 	printf("testing espeak_SetVoiceByProperties: languages=\"zzz\" (invalid)\n");

tests/encoding.c

 #include <espeak-ng/espeak_ng.h>
 #include <espeak-ng/encoding.h>
 
-void
+static void
 test_unbound_text_decoder()
 {
 	printf("testing unbound text decoder\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_unknown_encoding()
 {
 	printf("testing unknown encodings\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_us_ascii_encoding()
 {
 	printf("testing US-ASCII encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_koi8_r_encoding()
 {
 	printf("testing KOI8-R encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iscii_encoding()
 {
 	printf("testing ISCII encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_1_encoding()
 {
 	printf("testing ISO-8859-1 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_2_encoding()
 {
 	printf("testing ISO-8859-2 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_3_encoding()
 {
 	printf("testing ISO-8859-3 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_4_encoding()
 {
 	printf("testing ISO-8859-4 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_5_encoding()
 {
 	printf("testing ISO-8859-5 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_6_encoding()
 {
 	printf("testing ISO-8859-6 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_7_encoding()
 {
 	printf("testing ISO-8859-7 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_8_encoding()
 {
 	printf("testing ISO-8859-8 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_9_encoding()
 {
 	printf("testing ISO-8859-9 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_10_encoding()
 {
 	printf("testing ISO-8859-10 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_11_encoding()
 {
 	printf("testing ISO-8859-11 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_13_encoding()
 {
 	printf("testing ISO-8859-13 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_14_encoding()
 {
 	printf("testing ISO-8859-14 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_15_encoding()
 {
 	printf("testing ISO-8859-15 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_8859_16_encoding()
 {
 	printf("testing ISO-8859-16 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_utf_8_encoding()
 {
 	printf("testing UTF-8 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_iso_10646_ucs_2_encoding()
 {
 	printf("testing ISO-10646-UCS-2 encoding\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_char_decoder()
 {
 	printf("testing char decoder\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_wchar_decoder()
 {
 	printf("testing wchar_t decoder\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_auto_decoder()
 {
 	printf("testing auto decoder (UTF-8 + codepage-based fallback)\n");
 	destroy_text_decoder(decoder);
 }
 
-void
+static void
 test_peekc()
 {
 	printf("testing peekc\n");

tests/readclause.c

 	return text_decoder_decode_string(p_decoder, text, -1, ESPEAKNG_ENCODING_UTF_8);
 }
 
-void
+static void
 test_latin()
 {
 	printf("testing Latin (Latn)\n");
 	assert(clause_type_from_codepoint(0x2026) == (CLAUSE_SEMICOLON | CLAUSE_SPEAK_PUNCTUATION_NAME | CLAUSE_OPTIONAL_SPACE_AFTER));
 }
 
-void
+static void
 test_latin_sentence()
 {
 	printf("testing Latin (Latn) ... sentence\n");
 	assert(charix_top == 0);
 }
 
-void
+static void
 test_greek()
 {
 	printf("testing Greek (Grek)\n");
 	assert(clause_type_from_codepoint(0x0387) == CLAUSE_SEMICOLON);
 }
 
-void
+static void
 test_armenian()
 {
 	printf("testing Armenian (Armn)\n");
 	assert(clause_type_from_codepoint(0x0589) == (CLAUSE_PERIOD | CLAUSE_OPTIONAL_SPACE_AFTER));
 }
 
-void
+static void
 test_arabic()
 {
 	printf("testing Arabic (Arab)\n");
 	assert(clause_type_from_codepoint(0x06D4) == CLAUSE_PERIOD);
 }
 
-void
+static void
 test_devanagari()
 {
 	printf("testing Devanagari (Deva)\n");
 	assert(clause_type_from_codepoint(0x0964) == (CLAUSE_PERIOD | CLAUSE_OPTIONAL_SPACE_AFTER));
 }
 
-void
+static void
 test_tibetan()
 {
 	printf("testing Tibetan (Tibt)\n");
 	assert(clause_type_from_codepoint(0x0F0E) == CLAUSE_PARAGRAPH);
 }
 
-void
+static void
 test_sinhala()
 {
 	printf("testing Sinhala (Sinh)\n");
 	assert(clause_type_from_codepoint(0x0DF4) == (CLAUSE_PERIOD | CLAUSE_OPTIONAL_SPACE_AFTER));
 }
 
-void
+static void
 test_georgian()
 {
 	printf("testing Georgian (Geor)\n");
 	assert(clause_type_from_codepoint(0x10FB) == CLAUSE_PARAGRAPH);
 }
 
-void
+static void
 test_ethiopic()
 {
 	printf("testing Ethiopic (Ethi)\n");
 	assert(clause_type_from_codepoint(0x1368) == CLAUSE_PARAGRAPH);
 }
 
-void
+static void
 test_ideographic()
 {
 	printf("testing Ideographic (Hani)\n");
 	assert(clause_type_from_codepoint(0x3002) == (CLAUSE_PERIOD | CLAUSE_OPTIONAL_SPACE_AFTER));
 }
 
-void
+static void
 test_fullwidth()
 {
 	printf("testing Full Width\n");
 	assert(clause_type_from_codepoint(0xFF1F) == (CLAUSE_QUESTION | CLAUSE_OPTIONAL_SPACE_AFTER));
 }
 
-void
+static void
 test_uts51_emoji_character()
 {
 	printf("testing Emoji ... UTS-51 ED-3. emoji character\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_text_presentation_sequence()
 {
 	printf("testing Emoji ... UTS-51 ED-8a. text presentation sequence\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_emoji_presentation_sequence()
 {
 	printf("testing Emoji ... UTS-51 ED-9a. emoji presentation sequence\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_emoji_modifier_sequence()
 {
 	printf("testing Emoji ... UTS-51 ED-13. emoji modifier sequence\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_emoji_flag_sequence()
 {
 	printf("testing Emoji ... UTS-51 ED-14. emoji flag sequence\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_emoji_tag_sequence_emoji_character()
 {
 	printf("testing Emoji ... UTS-51 ED-14a. emoji tag sequence (emoji character)\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_emoji_combining_sequence()
 {
 	printf("testing Emoji ... UTS-51 ED-14b. emoji combining sequence\n");
 	assert(voice_change_name[0] == 0);
 }
 
-void
+static void
 test_uts51_emoji_keycap_sequence()
 {
 	printf("testing Emoji ... UTS-51 ED-14c. emoji keycap sequence\n");