GCC -pie patch (kinda) ....

[Michael Casadevall <sonicmctails@gmail.com>]

As some of you are aware, I've recently voluteered (or been voluteered 
depending on how you look at it) to work on correcting some of the more 
outstanding bugs with binutils, and gcc. I've been working on debugging 
the -pie issue with GCC which creates the following compiler errors

bc_nonshared.a(elf-init.oST): In function `__libc_csu_init':
elf-init.c:(.text+0x1c): undefined reference to `__init_array_start'
elf-init.c:(.text+0x26): undefined reference to `__init_array_end'
elf-init.c:(.text+0x44): undefined reference to `__init_array_end'
/opt/crosstool/gcc-4.1.1-glibc-2.3.6/m68k-unknown-linux-gnu/bin/../lib/gcc/m68k-unknown-linux-gnu/4.1.2/../../../../m68k-unknown-linux-gnu/lib/libc_nonshared.a(elf-init.oST): 
In function `__libc_csu_fini':
elf-init.c:(.text+0x6e): undefined reference to `__fini_array_end'
elf-init.c:(.text+0x76): undefined reference to `__fini_array_start'
elf-init.c:(.text+0x8a): undefined reference to `__fini_array_start'
collect2: ld returned 1 exit status

Right now, I've developed a no-op patch, but its just a fugly way to work 
around the problem, which I haven't fully idenified yet. The problem stems 
from glibc, from csu/elf-init.c

#ifdef HAVE_INITFINI_ARRAY
/* These magic symbols are provided by the linker.  */
extern void (*__preinit_array_start []) (void) attribute_hidden;
extern void (*__preinit_array_end []) (void) attribute_hidden;
extern void (*__init_array_start []) (void) attribute_hidden;
extern void (*__init_array_end []) (void) attribute_hidden;
extern void (*__fini_array_start []) (void) attribute_hidden;
extern void (*__fini_array_end []) (void) attribute_hidden;
#endif

/* These function symbols are provided for the .init/.fini section entry
     points automagically by the linker.  */
extern void _init (void);
extern void _fini (void);

HAVE_INITFINI_ARRAY is determined on the fly by autotools at compile time 
to tell if the linker supports ELF sections  .init_array, .finit_array, 
and .preinit_array. From what I can tell by reading binutils linker 
scripts, this SHOULD be supported on any platform that has ELF support, 
but I can't determine it for sure (binutils linker scripts give me a 
headache).

It's possible that since we do not support TLS, our linker no longer 
supports these, in which case the proper course of action would be 
to fix it in glibc, otherwise, figure out why binutils isn't outputting 
these sections into the resulting binary files. My next course of action 
is to dive into the ELF specification (bleck), and figure out what, if 
anything these sections do, but its quite possible this task is over my 
head. In addition, by making -pie a no-op, we at least have a fix.

I'll post the no-op patch if its wanted, and if anyone has ANY idea where 
I should look, or any thoughts and suggestions, it would be greatly 
appericated.
Michael