To properly support legacy ARM shared libraries, libc.so needs
to export the symbols __dso_handle and atexit, even though
these are now supplied by the crt startup code.
This patch reshuffles the existing CRT_LEGACY_WORKAROUND
conditionally compiled code slightly so it works as the
original author likely intended.
Change-Id: Id6c0e94dc65b7928324a5f0bad7eba6eb2f464b9
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@gmail.com>
Rewrite
crtbegin.S -> crtbegin.c
crtbegin_so.S -> crtbegin_so.c
This change allows us to generate PIC code without relying
on text relocations.
As a consequence of this rewrite, also rewrite
__dso_handle.S -> __dso_handle.c
__dso_handle_so.S -> __dso_handle_so.c
atexit.S -> atexit.c
In crtbegin.c _start, place the __PREINIT_ARRAY__, __INIT_ARRAY__,
__FINI_ARRAY__, and __CTOR_LIST__ variables onto the stack, instead of
passing a pointer to the text section of the binary.
This change appears sorta wonky, as I attempted to preserve,
as much as possible, the structure of the original assembly.
As a result, you have C files including other C files, and other
programming uglyness.
Result: This change reduces the number of files with text-relocations
from 315 to 19 on my Android build.
Before:
$ scanelf -aR $OUT/system | grep TEXTREL | wc -l
315
After:
$ scanelf -aR $OUT/system | grep TEXTREL | wc -l
19
Change-Id: Ib9f98107c0eeabcb606e1ddc7ed7fc4eba01c9c4
