[Bug other/36572] New: Documentation for some options starting with “no-” not clear

["n-roeser at gmx dot net" <gcc-bugzilla at gcc dot gnu dot org>]

>From the gcc-4.3.1 manual:
> -fno-sched-interblock
>     Don't schedule instructions across basic blocks.  This is normally
>     enabled by default when scheduling before register allocation,
>     i.e.  with -fschedule-insns or at -O2 or higher.
> 
> -fno-sched-spec
>     Don't allow speculative motion of non-load instructions.  This is
>     normally enabled by default when scheduling before register
>     allocation, i.e. with -fschedule-insns or at -O2 or higher.

The meaning of the second sentence for each option cannot be clearly
understood.  From reading the man page, I cannot say what the defaults are for
these settings.

In the first case: is scheduling of instructions across basic blocks enabled by
default when [â?¦], or is the option to /disable/ it enabled by default when
[â?¦]?

In the second case: Is speculative motion of non-load instructions enabled by
default when [â?¦], or is /not allowing it/ enabled by default when [â?¦]?

Please change the wording to make things clear. Perhaps the meaning can be
expressed without a negation, with a changed sentence structure, and/or with an
additional sentence giving an explanation.


-- 
           Summary: Documentation for some options starting with â??no-â??
                    not clear
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: other
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: n-roeser at gmx dot net


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36572