[Bug middle-end/107117] "atan2" fails to set the floating-point inexact exception due to constant folding, in some cases
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107117 --- Comment #5 from Richard Biener --- Btw, we only avoid inexact constant foldings for -frounding-math, not with -ftrapping-math (which guards FP exception state). See do_mpfr_ckconv. So we could do better here if we want (but then if at runtime the inexact exception is raised is unspecified).
[Bug middle-end/107117] "atan2" fails to set the floating-point inexact exception due to constant folding, in some cases
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107117 --- Comment #4 from Andreas Schwab --- Whether the inexact exception is raised or not is unspecified in general, and atan2 is no exception.