Commit graph

25 commits

Author SHA1 Message Date
Ryan Prichard
bcea0e2afd Call __emutls_unregister_key on dlclose
We want to delay the emutls pthread key deletion to keep
__thread/thread_local variables working as long as possible.

Currently, emutls has its own __attribute__((destructor)) function that
deletes its pthread key. That function runs even on process exit, and it
can run before other destructor functions and before C++ static object
destructors.

Move the destructor function to crtbegin_so.c, where an
__attribute__((destructor)) function is only called on dlclose. Use a
priority 0 destructor, which runs after every destructor with a default or
greater priority value.

__emutls_unregister_key will still run before destructor functions of
DT_NEEDED solibs. It also still leaks memory (both the emutls arrays and
each emutls object).

Bug: b/80453944
Test: manual
Change-Id: I6789bcf168415ab8badf2f64687c6a0136c5c917
2018-06-19 13:22:36 -07:00
Treehugger Robot
5bf2c20f43 Merge "crtbegin: Correctly align ESP to 16 for __i386__" 2018-02-09 06:56:31 +00:00
Ryan Prichard
a0d177d010 crtbegin: Correctly align ESP to 16 for __i386__
The (lowest) address of the argument area (aka ESP immediately prior to
the call instruction) must be aligned to 0 mod 16. Here, it is aligned to
12 mod 16.

From the SysV ABI doc (2.2.2 The Stack Frame)

"""The end of the input argument area shall be aligned on a 16 (32, if
__m256 is passed on stack) byte boundary. In other words, the value
(%esp + 4) is always a multiple of 16 (32) when control is transferred to
the function entry point."""

Test: extract code into a separate C file and verify stack alignment in a
  "start_main" function
Test: use the upcoming NDK r17-beta1 (with new Bionic crtbegin*.o files)
  with an M-23 x86 system image, check alignment in main (compiled with
  Clang not GCC, compiled w/o -mstackrealign)
Bug: b/73140672

Change-Id: Ia8d93fe5668d0a514a9fd22c40bf8362805111e6
2018-02-08 20:55:57 -08:00
Dan Albert
3e4d4d4cf2 Add _FORCE_CRT_ATFORK config for crtbegin.
libc.a is always the latest library regardless of target API level.

Test: treehugger
Bug: None
Change-Id: I844dc85a9283693b01d0fbdc26854bde82c750dc
2018-01-24 22:36:31 -08:00
Dan Albert
586b6761d0 Partial revert of "Remove obsolete __stack_chk_fail_local."
These sources are going to be used for the NDK as well, and the NDK
still uses GCC.

This partially reverts commit
4af220cfef. That commit also removed
this symbol from the linker's crtbegin (it has its own). That is
still only built with Clang, so we don't need to revert that part.

Test: treehugger
Bug: None
Change-Id: Iba231baf298e228135bdf48dfed87f9089975eb1
2018-01-24 16:37:48 -08:00
Dan Albert
2e2c72d61f Pre-M and GCC compatibility for crtbegin.
We're going to start using the bionic sources for the NDK CRT
objects, so we need to avoid using symbols that weren't around in
early versions of Android. The NDK is currently building the CRT
objects with GCC as well (there were some segfaults that have yet to
be diagnosed), so move `__used` to the GCC compatible location.

Test: treehugger
Bug: None
Change-Id: I1f5c23eafadc2e3bc0b84bc3305f79a04d35c7d8
2018-01-24 16:37:48 -08:00
Elliott Hughes
12533271fb Give ELF notes 4-byte alignment.
Use .balign because what the argument means doesn't vary between
architectures.

Bug: http://b/70166421
Test: builds
Change-Id: I1d54f2f6942dd2893f3fda30bac08d07ea9cd346
2017-12-04 13:21:01 -08:00
Elliott Hughes
3413a75460 Remove an obsolete aarch64 hack.
e210488e0d in 2013 added this, which seems
to have been a workaround for the linker at the time that was never removed.

Bug: N/A
Test: ran tests
Change-Id: I171c3f4b7c34638ab75b8e49616b3a9c24ab3fcb
2017-10-25 10:57:02 -07:00
Elliott Hughes
b348d5cda8 Build crtbegin with clang too.
If _start_main is static, clang optimizes it out and then generates an
undefined reference from the inline assembler, so let's explicitly tell
the compiler it's used.

Bug: N/A
Test: ran tests
Change-Id: Iba3d9c63abae9a0dc32f236b01783515f0190956
2017-07-25 11:54:33 -07:00
Elliott Hughes
4af220cfef Remove obsolete __stack_chk_fail_local.
Clang doesn't use this.

Bug: N/A
Test: x86 emulator builds and boots
Change-Id: I2865c0d568a644f61f34bdea539daff5224896bc
2017-05-23 16:43:30 -07:00
Elliott Hughes
94072fbb4e Switch to inline assembler in crtbegin.
Using __builtin_frame_address was clever, but didn't work for arm64 (for
reasons which were never investigated) and the ChromeOS folks claim it
causes trouble for x86 with ARC++ (though without a reproduceable test case).

Naked functions turn out to be quite unevenly supported: some architectures
do the right thing, others don't; some architectures warn, others don't (and
the warnings don't always match the platforms that _actually_ have problems).

Inline assembler also removes the guessing games: everyone knows what the
couple of instructions _ought_ to be, and now we don't have to reason about
what the compiler will actually do (yet still keep the majority of the code
in C).

Bug: N/A
Test: builds, boots
Change-Id: I14207ef50ca46b6eca273c3cb7509c311146a3ca
2017-05-23 14:47:16 -07:00
Dmitriy Ivanov
af7e806cec Properly align init/fini_arrays for crtend.o
Also remove them from crtend_so.o

Bug: http://b/20532404
Change-Id: I56a0f80c4b3a83cf11d28bbf17791ff4ce10c5d2
(cherry picked from commit e543c7612e)
2015-05-07 12:56:15 -07:00
Dmitriy Ivanov
ea295f68f1 Unregister pthread_atfork handlers on dlclose()
Bug: http://b/20339788
Change-Id: I874c87faa377645fa9e0752f4fc166d81fd9ef7e
2015-04-24 17:57:37 -07:00
Dimitry Ivanov
094f58fb2a Revert "Unregister pthread_atfork handlers on dlclose()"
The visibility control in pthread_atfork.h is incorrect.
 It breaks 64bit libc.so by hiding pthread_atfork.

 This reverts commit 6df122f852.

Change-Id: I21e4b344d500c6f6de0ccb7420b916c4e233dd34
2015-04-24 03:46:57 +00:00
Dmitriy Ivanov
6df122f852 Unregister pthread_atfork handlers on dlclose()
Change-Id: I326fdf6bb06bed12743f08980b5c69d849c015b8
2015-04-22 19:19:37 -07:00
Colin Cross
e09ab2cc2f Make .note.android.ident section type SH_NOTE
The .note.android.ident section is only used by GDB, which doesn't
care what section type the section is, but it would be convenient
for readelf -n to be able to find the section too.

The old way of getting the .note.android.ident section to be of type
SH_NOTE involved compiling from .c to .s using gcc, running sed to
change progbits to note, and then compiling from .s to .o using gcc.
Since crtbrand.c only contains a section containing data, a
crtbrand.S can be checked in that will compile on all platforms,
avoiding the need for sed.

Also add crtbrand.o to crtbegin_so.o so that libraries also get
the note, and to the crt workaround in arm libc.so.

Change-Id: Ica71942a6af4553b56978ceaa288b3f4c15ebfa2
2015-02-12 21:37:20 -08:00
Dmitriy Ivanov
4b41555ba5 Revert "Register __libc_fini as early as possible."
This reverts commit e880c736d6.

Change-Id: Ide83e442eb5dbfef5298a15bc602c3fe1dda1862
2014-09-04 21:54:34 +00:00
Dmitriy Ivanov
e880c736d6 Register __libc_fini as early as possible.
We want __libc_fini to be called after all the destructors.

Bug: 14611536
Change-Id: Ibb83a94436795ec178fd605fa531ac29608f4a3e
2014-09-03 15:27:29 -07:00
Dmitriy Ivanov
6b56691a67 Fixes for __cxa_finalize
* Ability to register atexit handler from atexit handler
  * Correct way to handle both forms of atexit handler

Bug: https://code.google.com/p/android/issues/detail?id=66595
Bug: 4998315
Change-Id: I39529afaef97b6e1469c21389d54c0d7d175da28
2014-05-05 11:36:57 -07:00
Serban Constantinescu
e210488e0d AArch64: Add initial support for AArch64
This is the first patch out of a series of patches that add support for
AArch64, the new 64bit execution state of the ARMv8 Architecture. The
patches add support for LP64 programming model.

The patch adds:
* "arch-aarch64" to the architecture directories.
* "arch-aarch64/include" - headers used by libc
* "arch-aarch64/bionic":
    - crtbegin, crtend support;
    - aarch64 specific syscall stubs;
    - setjmp, clone, vfork assembly files.

Change-Id: If72b859f81928d03ad05d4ccfcb54c2f5dbf99a5
Signed-off-by: Serban Constantinescu <serban.constantinescu@arm.com>
2013-12-16 17:00:22 -08:00
Pavel Chupin
33a209e575 Fix 16-byte stack alignment requirement for x86_64 ABI
Change-Id: I43304803ac54c8688c61688bd96c7160614172d4
Signed-off-by: Pavel Chupin <pavel.v.chupin@intel.com>
2013-10-21 17:36:28 -07:00
Elliott Hughes
eb847bc866 Fix x86_64 build, clean up intermediate libraries.
The x86_64 build was failing because clone.S had a call to __thread_entry which
was being added to a different intermediate .a on the way to making libc.so,
and the linker couldn't guarantee statically that such a relocation would be
possible.

  ld: error: out/target/product/generic_x86_64/obj/STATIC_LIBRARIES/libc_common_intermediates/libc_common.a(clone.o): requires dynamic R_X86_64_PC32 reloc against '__thread_entry' which may overflow at runtime; recompile with -fPIC

This patch addresses that by ensuring that the caller and callee end up in the
same intermediate .a. While I'm here, I've tried to clean up some of the mess
that led to this situation too. In particular, this removes libc/private/ from
the default include path (except for the DNS code), and splits out the DNS
code into its own library (since it's a weird special case of upstream NetBSD
code that's diverged so heavily it's unlikely ever to get back in sync).

There's more cleanup of the DNS situation possible, but this is definitely a
step in the right direction, and it's more than enough to get x86_64 building
cleanly.

Change-Id: I00425a7245b7a2573df16cc38798187d0729e7c4
2013-10-09 16:00:17 -07:00
synergydev
589eaa4c72 libc: fix __cxa_atexit implicit declaration
Change-Id: Iacad18b332a717e4485c83df4bd42a850ff7699f
2013-10-07 11:33:20 -07:00
Pavel Chupin
719269db18 Fixed ASM_ALIGN macro
Got it all wrong on first patch. Somehow that didn't affect system
build, neither arm nor x86... something to think about.

Change-Id: I45416d843aad44af62841c6f6ab607ccf3f012ea
Signed-off-by: Pavel Chupin <pavel.v.chupin@intel.com>
2013-10-04 11:12:58 +04:00
Pavel Chupin
b49c17c2bf Move common arch-* code to arch-common directory
Will be helpful on adding x86_64

Change-Id: I96cf6fc7912c02f289c75f07ae0079c32d69173f
Signed-off-by: Pavel Chupin <pavel.v.chupin@intel.com>
2013-10-03 11:14:33 +04:00