From 193bc3702f35bc7b60ffd79e4f41ecd5db1fd383 Mon Sep 17 00:00:00 2001 From: Jim Mussared Date: Sat, 7 Dec 2019 22:31:04 +1100 Subject: [PATCH] mpy-cross/README.md: Add notes about -march and -O. --- mpy-cross/README.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mpy-cross/README.md b/mpy-cross/README.md index e35b28b69..bf743a903 100644 --- a/mpy-cross/README.md +++ b/mpy-cross/README.md @@ -22,4 +22,10 @@ the unix port of MicroPython requires the following: $ ./mpy-cross -mcache-lookup-bc foo.py +If the Python code contains `@native` or `@viper` annotations, then you must +specify `-march` to match the target architecture. + Run `./mpy-cross -h` to get a full list of options. + +The optimisation level is 0 by default. Optimisation levels are detailed in +https://docs.micropython.org/en/latest/library/micropython.html#micropython.opt_level