------- Comment #4 from terry at chem dot gu dot se 2007-11-27 22:56 ------- (In reply to comment #3) (Admittedly from the 4.2.2 manual): 2.2 Options controlling Fortran dialect -frange-check Enable range checking on results of simplification of constant expressions during compilation. For example, by default, GNU Fortran will give an overflow error at compile time when simplifying a = EXP(1000). With -fno-range-check, no error will be given and the variable a will be assigned the value +Infinity. Similarly, DATA i/Z'FFFFFFFF'/ will result in an integer overflow on most systems, but with -fno-range-check the value will “wrap around” and i will be initialized to -1 instead. That seems pretty explicit about what the option is supposed to be doing. Referring to compiler output agreeing with itself is not a particularly strong argument. Surely it's reasonable for the programmer to assume that if y is +Inf, than log(y) will be also. (Though I can see this degenerating into a discussion about -ffloat-store.) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34230