Okay, this is for @c-mauderer or anyone else who can answer definitively. Based on the dicourse post. I’ve create a PR for the gnu-gcc-mirror on github with the change. Once this change goes in, there is a two line change to spec/build/bsps/arm/stm32u5/abi.yml to add the -mfloat-abi=hard and -mfpu=fpv5-sp-d16 CFLAGS to the abi. With that patch the BSP is built with hard floats, I’ve built the stm32u5-discovery BSP and verified it both uses hard floats and is much faster for my graphics code .
So what are the next steps to get this merged upstream.
I’m not sure where it is documented but at some point it was suggested to me that the next step for contrib projects is to discuss the change in an MR here:
Contrib / gcc · GitLab · RTEMS Project
Obviously nearly no one does that. There are only 5 closed MRs in the whole contrib section of the RTEMS GitLab. But there are some patches from RTEMS contributors in the projects that are mirrored there.
If no one objects there, the next step is the normal patch submission process at gcc:
Contributing to GCC - GNU Project
Note that gcc expects a signed-off line to signal that you accepted their DCO.