https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66458
--- Comment #5 from Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> ---
The comment in the front-end confirms the original intent, which is that FPU
shouldn't be messed with if the user didn't explicitly request it:
/* If -ffpe-trap option was provided, add a call to set_fpe so that
the library will raise a FPE when needed. */
The patch below makes libgfortran behave in the same way:
Index: runtime/main.c
===================================================================
--- runtime/main.c (revision 226632)
+++ runtime/main.c (working copy)
@@ -263,7 +263,11 @@ init (void)
init_variables ();
init_units ();
- set_fpu ();
+
+ /* If (and only if) the user asked for it, set up the FPU state. */
+ if (options.fpe != 0)
+ set_fpu ();
+
init_compile_options ();
#ifdef DEBUG
