This removes all encouragement to use -fwhole-program with -flto
from the documentation. As can be seen in PR56533 it can be
most confusing ... instead advise to rely on a linker plugin.
Ok?
Thanks,
Richard.
2013-03-05 Richard Biener <rguent...@suse.de>
* doc/invoke.texi (fwhole-program): Discourage use in combination
with -flto.
Index: gcc/doc/invoke.texi
===================================================================
*** gcc/doc/invoke.texi (revision 196451)
--- gcc/doc/invoke.texi (working copy)
*************** Enabled by default with @option{-funroll
*** 8168,8182 ****
Assume that the current compilation unit represents the whole program being
compiled. All public functions and variables with the exception of
@code{main}
and those merged by attribute @code{externally_visible} become static
functions
! and in effect are optimized more aggressively by interprocedural optimizers.
If @command{gold} is used as the linker plugin, @code{externally_visible}
attributes are automatically added to functions (not variable yet due to a
current @command{gold} issue) that are accessed outside of LTO objects
according to resolution file produced by @command{gold}. For other linkers
that cannot generate resolution file, explicit @code{externally_visible}
attributes are still necessary.
! While this option is equivalent to proper use of the @code{static} keyword for
! programs consisting of a single file, in combination with option
! @option{-flto} this flag can be used to
! compile many smaller scale programs since the functions and variables become
! local for the whole combined compilation unit, not for the single source file
! itself.
! This option implies @option{-fwhole-file} for Fortran programs.
@item -flto[=@var{n}]
@opindex flto
--- 8168,8178 ----
Assume that the current compilation unit represents the whole program being
compiled. All public functions and variables with the exception of
@code{main}
and those merged by attribute @code{externally_visible} become static
functions
! and in effect are optimized more aggressively by interprocedural optimizers.
! In combination with @code{-flto} using this option should not be used.
! Instead relying on a linker plugin should provide safer and more precise
! information.
@item -flto[=@var{n}]
@opindex flto
