There is no way to force 'long double' to be 64bit for aarch64
. No -mlong-double-64
neither -fno-long-double
are supported.
arm has published detailed manual for fixing this issue: https://developer.arm.com/documentation/ka004751/latest/
The idea is to take library functions from the LLVM 'compiler-rt' project, compile them and link with your application.