MacOS Build

[tuxpoldo]

In order to successfully build piper on MacOS devices (Intel or Apple Silicon), the follwing pull requests have to be merged:

• Fixed missing function declaration that prevents build on modern C compilers espeak-ng/espeak-ng#1811
• Added support for MacOS (Intel and Apple Silicon) piper-phonemize#11

When trying to run the freshly built executable on a Mac, please keep in mind that the executable will not find the phontab file since it is not located where expected. In order to test the successful compilation, run the following command after downloading the required models:

echo 'Welcome to the Machine!' | build/piper -m en_US-lessac-medium.onnx -f welcome.wav  --espeak_data
 ./install/espeak-ng-data

[synesthesiam]

Merged! A test build for macOS is available here: https://github.com/rhasspy/piper/releases/tag/2023.9.27-1