Submitted on behalf of Armando Montanez (amontanez@google.com).
Objects with unused program headers copied by objcopy would always have
nonzero values for program header offset and program header entry size.
While technically valid, this atypical behavior triggers warnings in some
tools. This change sets the two fields to zero when the program header is
unused, better fitting the general expectations for unused program header
data.
Section headers behaved somewhat similarly (though only with the entry size),
and are fixed in this revision as well.
Differential Revision: https://reviews.llvm.org/D51961
llvm-svn: 342065
Third Attempt:
- Alignment issues resolved.
- zlib::isAvailable() detected.
- ArrayRef misuse fixed.
Usage:
llvm-objcopy --compress-debug-sections=zlib foo.o
llvm-objcopy --compress-debug-sections=zlib-gnu foo.o
In both cases the debug section contents is compressed with zlib. In the GNU
style case the header is the "ZLIB" magic string followed by the uint64 big-
endian decompressed size. In the non-GNU mode the header is the
Elf(32|64)_Chdr.
Decompression support is coming soon.
Differential Revision: https://reviews.llvm.org/D49678
llvm-svn: 341635
Second Attempt. Alignment issues resolved. zlib::isAvailable() detected.
Usage:
llvm-objcopy --compress-debug-sections=zlib foo.o
llvm-objcopy --compress-debug-sections=zlib-gnu foo.o
In both cases the debug section contents is compressed with zlib. In the GNU
style case the header is the "ZLIB" magic string followed by the uint64 big-
endian decompressed size. In the non-GNU mode the header is the
Elf(32|64)_Chdr.
Decompression support is coming soon.
Differential Revision: https://reviews.llvm.org/D49678
llvm-svn: 341607
Summary:
Allow strip to be called on multiple input files, which is interpreted as stripping N files in place. Using multiple input files is incompatible with -o.
To allow this, create a `DriverConfig` struct which just wraps a list of `CopyConfigs`. objcopy will only ever have a single `CopyConfig`, but strip will have N (where N >= 1) CopyConfigs.
Reviewers: alexshap, jakehehrlich
Reviewed By: alexshap, jakehehrlich
Subscribers: MaskRay, jakehehrlich, llvm-commits
Differential Revision: https://reviews.llvm.org/D51660
llvm-svn: 341464
Summary:
Fixes the error "Link field value 0 in section .rela.plt is invalid" when copying/stripping certain binaries. Minimal repro:
```
$ cat /tmp/a.c
int main() { return 0; }
$ clang -static /tmp/a.c -o /tmp/a
$ llvm-strip /tmp/a -o /tmp/b
llvm-strip: error: Link field value 0 in section .rela.plt is invalid.
```
Reviewers: jakehehrlich, alexshap
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D51493
llvm-svn: 341419
Also reverts follow-up commits r341343 and r341344.
The primary commit continues to break some build bots even after the
fixes in r341343 for UBSan issues:
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-full/builds/5823
It is also failing for me locally (linux, x86-64).
llvm-svn: 341360
Usage:
llvm-objcopy --compress-debug-sections=zlib foo.o
llvm-objcopy --compress-debug-sections=zlib-gnu foo.o
In both cases the debug section contents is compressed with zlib. In the GNU
style case the header is the "ZLIB" magic string followed by the uint64 big-
endian decompressed size. In the non-GNU mode the header is the
Elf(32|64)_Chdr.
Decompression support is coming soon.
Differential Revision: https://reviews.llvm.org/D49678
llvm-svn: 341342
The restoreDateOnFile() method used to preserve dates uses sys::fs::openFileForWrite(). That method defaults to opening files with CD_CreateAlways, which truncates the output file if it exists. Use CD_OpenExisting instead to open it and *not* truncate it, which also has the side benefit of erroring if the file does not exist (it should always exist, because we just wrote it out).
Also, fix the test case to make sure the output is a valid output file, and not empty. The extra test assertions are enough to catch this regression.
llvm-svn: 340996
Summary: Before, llvm-strip accepted a second argument but it would just be ignored.
Reviewers: alexshap, jhenderson, paulsemel
Reviewed By: alexshap
Subscribers: jakehehrlich, rupprecht, llvm-commits
Differential Revision: https://reviews.llvm.org/D51004
llvm-svn: 340229
Summary:
Port GNU Objcopy -G/--keep-global-symbol(s).
This is slightly different than the already-implemented --globalize-symbol, which marks a symbol as global when copying. When --keep-global-symbol (alias -G) is used, *only* those symbols marked will stay global, and all other globals are demoted to local. (Also note that it doesn't *promote* a symbol to global). Additionally, there is a pluralized version of the flag --keep-global-symbols, which effectively applies --keep-global-symbol for every non-comment in a file.
Reviewers: jakehehrlich, jhenderson, alexshap
Reviewed By: jhenderson
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D50589
llvm-svn: 340105
Summary:
The -I (--input-target) and -B (--binary-architecture) flags exist but are currently silently ignored. This adds support for -I binary for architectures i386, x86-64 (and alias i386:x86-64), arm, aarch64, sparc, and ppc (powerpc:common64). This is largely based on D41687.
This is done by implementing an additional subclass of Reader, BinaryReader, which works by interpreting the input file as contents for .data field, sets up a synthetic header, and adds additional sections/symbols (e.g. _binary__tmp_data_txt_start).
Reviewers: jakehehrlich, alexshap, jhenderson, javed.absar
Reviewed By: jhenderson
Subscribers: jyknight, nemanjai, kbarton, fedor.sergeev, jrtc27, kristof.beyls, paulsemel, llvm-commits
Differential Revision: https://reviews.llvm.org/D50343
llvm-svn: 340070
Summary:
Add support for --rename-section flags from gnu objcopy.
Not all flags appear to have an effect for ELF objects, but allowing them would allow easier drop-in replacement. Other unrecognized flags are rejected.
This was only tested by comparing flags printed by "readelf -e <.o>" against the output of gnu vs llvm objcopy, it hasn't been tested to be valid beyond that.
Reviewers: jakehehrlich, alexshap
Subscribers: llvm-commits, paulsemel, alexshap
Differential Revision: https://reviews.llvm.org/D49870
llvm-svn: 338582
Summary:
See binutils-gdb/bfd/elf.c, GNU objcopy also strips .stab* (STABS)
.line* (DWARF 1) .gnu.linkonce.wi.* (linkonce section for .debug_info) but
I'm not sure we need to be compatible with it.
Reviewers: dblaikie, alexshap, jakehehrlich, jhenderson
Reviewed By: alexshap, jakehehrlich
Subscribers: aprantl, JDevlieghere, jakehehrlich, llvm-commits
Differential Revision: https://reviews.llvm.org/D50100
llvm-svn: 338443
Summary:
These two cases will trigger a dereference on a nullptr, since the
SymbolTable can be nonexistent for a given library, in addition to just
being empty.
Reviewers: alexshap
Reviewed By: alexshap
Subscribers: meikeb, kongyi, chh, jakehehrlich, llvm-commits, pirama
Differential Revision: https://reviews.llvm.org/D49534
llvm-svn: 338062
Summary:
Add basic support for --rename-section=old=new to llvm-objcopy.
A full replacement for GNU objcopy requires also modifying flags (i.e. --rename-section=old=new,flag1,flag2); I'd like to keep that in a separate change to keep this simple.
Reviewers: jakehehrlich, alexshap
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D49576
llvm-svn: 337604
Nest any classes not used outside of a file into anon. Nest any classes used
across files in llvm-objcopy into namespace llvm::objcopy.
Differential Revision: https://reviews.llvm.org/D49449
llvm-svn: 337337
Anywhere in tools/llvm-objcopy where functions or classes are not referenced
outside of a given file, we change things to make the function or class static
or put inside an anonymous namespace.
llvm-svn: 337220
This patch is an update of an older patch that never landed
(see here: https://reviews.llvm.org/D42516)
Recently various users have run into this issue and it just 100%
has to be solved at this point. The main difference in this patch
is that I use gunzip instead of unzip which should hopefully allow
tests to pass. Please review this as if it is a new patch however.
I found some issues along the way and made some minor modifications.
The binary used in this patch for testing (a zip file to make it small)
can be found here:
https://drive.google.com/file/d/1UjsnTO9edLttZibbr-2T1bJl92KEQFAO/view?usp=sharing
Differential Revision: https://reviews.llvm.org/D49206
llvm-svn: 337204
Summary:
This option appears to have been dropped as part of the refactoring in
r331663. Unfortunately, if we want to use llvm-strip as a drop-in
replacement for strip, this option should still be available.
Reviewers: alexshap
Reviewed By: alexshap
Subscribers: meikeb, kongyi, chh, jakehehrlich, llvm-commits, pirama
Differential Revision: https://reviews.llvm.org/D49226
llvm-svn: 336921
This diff adds support for handling static libraries
to llvm-objcopy and llvm-strip.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D48413
llvm-svn: 336455
The class Object contains std::shared_ptr<MemoryBuffer> OwnedData
which is not used anywhere. Besides avoiding two stage initialization
the motivation to remove it comes from the plan to add (currently missing) support
for static libraries.
NFC.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D47855
llvm-svn: 334217
This fixes the bug where strip-all option was
leading to a malformed outputted ELF file.
Differential Revision: https://reviews.llvm.org/D47414
llvm-svn: 333772
This diff implements the option -o
for specifying a file to write the output to.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D47505
llvm-svn: 333693
Per discussion on the generic-abi mailing list:
https://groups.google.com/forum/#!topic/generic-abi/MPr8TVtnVn4
An object file manipulation tool must either write out a symbol
table with the same number of entries as the original symbol table
and in the same order, or if this is impossible, refuse to operate
on the object file if it has unrecognized sections that are linked
to the symtab section. However, existing tools (namely GNU strip,
GNU objcopy and ld.{bfd,gold,lld} -r) do not comply with this at
present: they change symbol table indexes and set sh_link to 0 on
the unrecognized symtab-linked sections.
We intend to use the latter as a (temporary) signal that a tool has
operated on a proposed new symtab-linked section and invalidated the
symbol table indexes. However, llvm-objcopy currently keeps sh_link
pointing to the new symtab section. This patch changes llvm-objcopy
to set sh_link to 0 to match the behaviour of the other tools.
Differential Revision: https://reviews.llvm.org/D47404
llvm-svn: 333581
This is a small follow-up to the revisions r333117 and r331663.
1. Avoid the name conflicts of the generated variables for prefixes.
2. Apply clang-format -i -style=llvm to llvm-objcopy.cpp once again.
3. Add a test for the flag with double dash.
Test plan: make check-all
llvm-svn: 333120
If one runs llvm-objcopy --strip-all --keep-symbol foo
and the symbol table indeed contains the symbol "foo"
then it should not be removed.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D47052
llvm-svn: 333008
This option just keeps being a problem and really needs to be implemented
in some fashion. Implementing it properly requires some kind of
"replaceSectionReference" method because all the existing links need to be
maintained. The desired behavior is just for allocated sections to become
NOBITS but actually implementing that is rather tricky due to the current
design of llvm-objcopy. However converting allocated sections to NOBITS is
just an optimization and not something debuggers need. Debuggers can debug
a stripped executable and take an unstripped executable for that stripped
executable as input. Additionally allocated sections account for a very
small part of debug binaries so this optimization is quite small. I propose
that for the time being we implement this as a NOP so that people can use
llvm-objcopy where they need to, just in a sub-optimal way.
This option has already blocked a lot of people and its currently blocking me.
llvm-svn: 332396
This option permits to explicitly keep the specified
symbol so that it doesn't get removed.
Differential Revision: https://reviews.llvm.org/D46819
llvm-svn: 332356
Julie Hockett