Valgrind reports
==20307== Invalid write of size 1
==20307== at 0x4E856FE: Wavegen.part.1 (wavegen.c:880)
==20307== by 0x4E86682: Wavegen (wavegen.c:670)
==20307== by 0x4E86682: Wavegen2 (wavegen.c:1235)
==20307== by 0x4E86682: WavegenFill2 (wavegen.c:1317)
==20307== by 0x4E86CA7: WavegenFill (wavegen.c:1398)
==20307== by 0x4E7093F: Synthesize (speech.c:442)
==20307== by 0x4E712E0: sync_espeak_Synth (speech.c:549)
==20307== by 0x4E8A5C0: process_espeak_command (espeak_command.c:317)
==20307== by 0x4E8B387: say_thread (fifo.c:333)
==20307== by 0x50E85A9: start_thread (pthread_create.c:463)
==20307== by 0x53F5CBE: clone (clone.S:95)
==20307== Address 0xad5e1bd is 0 bytes after a block of size 2,205 alloc'd
==20307== at 0x4C2CABF: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==20307== by 0x4C2EE04: realloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==20307== by 0x4E70CFC: espeak_ng_InitializeOutput (speech.c:286)
==20307== by 0x4E6176E: espeak_Initialize (espeak_api.c:67)
==20307== by 0x10A5D8: initialize_espeak (espeak.c:303)
==20307== by 0x109D1D: main (espeakup.c:201)
==20307==
Indeed, the out_ptr >= out_end test is not enough: it only checks that
one byte can fit the buffer, while klatt and wavegen produce two bytes.
See issue #8, https://github.com/espeak-ng/espeak-ng/issues/8
There might still be some ints that could be changed to boolean.
Possible regressions in fifo.c:
int fifo_is_busy() and int fifo_is_command_enabled() used to return an int. Now they return a boolean. This might cause problems on systems where stdbool true/false is something else than 1/0.
This is from the old espeak RiscOS port that has been removed.
If/when the espeak-ng program is ported to RiscOS, this will be
done in a different, more maintainable way.