It seems object files are compiled with -mfloat-abi=hard but this build flag isn’t used in the final ELF linking stage.
Try adding a small extra script to append to the linker flags.
extra_scripts = link_hardfloat.py
with link_hardfloat.py in the project’s root directory
Import("env")
env.Append(LINKFLAGS=["-mfloat-abi=hard"])