Floating point differences between GCC-7 and GCC-9?

[David Aldrich via Gcc-help <gcc-help@xxxxxxxxxxx>]

Hi

We are comparing results from our C++ app on Ubuntu 18.04 (gcc 7.3.0, glibc
2.27 ) and Ubuntu 20.04 (gcc 9.3.0, glibc 2.31 ).  We are seeing
significant differences in floating point calculation results across these
platforms.

Were there significant changes to the floating point library in gcc 9?

Best regards
David