Walter, On 09/16/2013 04:57 PM, walter harms wrote: > > > Am 14.09.2013 14:05, schrieb walter harms: >> >> >> Am 13.09.2013 20:20, schrieb Michael Kerrisk (man-pages): >>> Walter, >>> >>> On Fri, Sep 13, 2013 at 6:46 PM, walter harms <wharms@xxxxxx> wrote: >>>> hi list, >>>> i was investigating this and the good news it that you still need a libm. >>>> On the other side the reporter is right he does not need to specify that. >>>> Obviously this depends on the linker script used. >>>> >>>> The math man pages say: "Link with -lm". >>>> Perhaps it is better to say 'You may need to Link with -lm". >>>> >>>> any comments on that ? >>> >>> >>> Thanks for looking at this bug. Could you elaborate a little more on >>> what it/sin't in the linker script that makes the difference? >>> >> >> I have no clue what linker magic is needed. >> > I know what it going on. the is no linker magic required. > The point is gcc build-ins. Some functions are replaced with > build-ins. That happens e.g. with fabs() what the original poster noted. > Disabling the build-ins with gcc -fno-builtin shows that the -lm is still > a requirement. Thanks! I hadn't thought of that. I see there is a list available in the gcc documentation at http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html > next problem, who will do the bugzilla-entry ? I will add something to https://bugzilla.kernel.org/show_bug.cgi?id=60749 Fundamentally, this is a gcc feature, and I don't think there's much that can be sensibly said about it in man-pages. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
