[Bug sanitizer/63361] Test case c-c++-common/ubsan/float-cast-overflow-1.c fails on Pentium2

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63361

--- Comment #10 from Martin Liška <marxin at gcc dot gnu.org> ---
It's a typical x87 code, where registers have better precision that a double.
Thus adding -ffloat-store fixed the test-case, I'll send a patch.