Strip a few more instructions from crt0-minrt.S:
- Remove "halt" and rely on the infinite loop after main()'s return.
- Remove main()'s argc and argv argument initialization. Host loader
does not set them, and typical firmware does not use them, either.
- Remove the __dso_handle symbol.
This should be safe because the default crt0.S is fully standards
compliant. Whereas crt0-minrt.S has been documented from the beginning
to intentionally miss features in order to reduce firmware size, while
still enabling typical PRU firmware to operate.
Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
Avoid a recursive make to speed things up a bit. This change was
inspired by the recent similar patch for c6x:
https://sourceware.org/pipermail/newlib/2023/020869.html
While at it, fork crt0-minrt.S into a separate source file instead of
relying on a predefined macro to generate two different object files.
This improves clarity, simplifies the build rules, and would allow
further optimization in crt0-minrt.S to be implemented more cleanly.
Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>