[Bug target/46770] Replace .ctors/.dtors with .init_array/.fini_array on targets supporting them

["hjl.tools at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46770

--- Comment #66 from H.J. Lu <hjl.tools at gmail dot com> 2011-06-23 23:17:04 UTC ---
(In reply to comment #65)
> The mainline versions of both GNU ld and gold now put .ctors sections into
> .init_array sections, and put .dtors sections into .fini_array sections. 
> .ctors/.dtors sections with priorities are sorted correctly with
> .init_array/.fini_array sections with priorities.
> 
> The gcc patch is still useful as it will permit eliminating the support for
> constructors and destructors in crtbegin.o and crtend.o.  If we can do that I
> believe that crtend.o can be removed, and crtbegin.o will only be needed to
> call 
> _Jv_RegisterClasses.

[hjl@gnu-6 libgcc]$ readelf -s crtend.o

Symbol table '.symtab' contains 11 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS crtstuff.c
     2: 0000000000000000     0 SECTION LOCAL  DEFAULT    1 
     3: 0000000000000000     0 SECTION LOCAL  DEFAULT    2 
     4: 0000000000000000     0 SECTION LOCAL  DEFAULT    3 
     5: 0000000000000000     0 SECTION LOCAL  DEFAULT    4 
     6: 0000000000000000     0 OBJECT  LOCAL  DEFAULT    4 __FRAME_END__
     7: 0000000000000000     0 SECTION LOCAL  DEFAULT    5 
     8: 0000000000000000     0 OBJECT  LOCAL  DEFAULT    5 __JCR_END__
     9: 0000000000000000     0 SECTION LOCAL  DEFAULT    7 
    10: 0000000000000000     0 SECTION LOCAL  DEFAULT    6 

We need __FRAME_END__ for exception handling and __JCR_END__ for
_Jv_RegisterClasses.