GNU objcopy can support output formats like elf32-i386-freebsd and
elf64-x86-64-freebsd. The only difference from their regular non-freebsd
counterparts that I have observed is that the freebsd versions set the
OS/ABI field to ELFOSABI_FREEBSD. This patch sets the OS/ABI field
according based on the format whenever --output-format is specified.
Reviewed by: rupprecht, grimar
Differential Revision: https://reviews.llvm.org/D59645
llvm-svn: 356737
This change makes linking into .build-id atomic and safe to use.
Some users under particular workflows are reporting that this races
more than half the time under particular conditions.
llvm-svn: 356404
This patch changes llvm-objcopy's behaviour to not strip sections that
are in segments, if they otherwise would be due to a stripping operation
(--strip-all, --strip-sections, --strip-non-alloc). This preserves the
segment contents. It does not change the behaviour of --strip-all-gnu
(although we could choose to do so), because GNU objcopy's behaviour in
this case seems to be to strip the section, nor does it prevent removing
of sections in segments with --remove-section (if a user REALLY wants to
remove a section, we should probably let them, although I could be
persuaded that warning might be appropriate). Tests have been added to
show this latter behaviour.
This fixes https://bugs.llvm.org/show_bug.cgi?id=41006.
Reviewed by: grimar, rupprecht, jakehehrlich
Differential Revision: https://reviews.llvm.org/D59293
This is a reland of r356129, attempting to fix greendragon failures
due to a suspected compatibility issue with od on the greendragon bots
versus other versions.
llvm-svn: 356136
This patch changes llvm-objcopy's behaviour to not strip sections that
are in segments, if they otherwise would be due to a stripping operation
(--strip-all, --strip-sections, --strip-non-alloc). This preserves the
segment contents. It does not change the behaviour of --strip-all-gnu
(although we could choose to do so), because GNU objcopy's behaviour in
this case seems to be to strip the section, nor does it prevent removing
of sections in segments with --remove-section (if a user REALLY wants to
remove a section, we should probably let them, although I could be
persuaded that warning might be appropriate). Tests have been added to
show this latter behaviour.
This fixes https://bugs.llvm.org/show_bug.cgi?id=41006.
Reviewed by: grimar, rupprecht, jakehehrlich
Differential Revision: https://reviews.llvm.org/D59293
llvm-svn: 356129
When --compress-debug-sections is given,
llvm-objcopy removes the uncompressed sections and adds compressed to the section list.
This makes all the pointers to old sections to be outdated.
Currently, code already has logic for replacing the target sections of the relocation
sections. But we also have to update the relocations by themselves.
This fixes https://bugs.llvm.org/show_bug.cgi?id=40885.
Differential revision: https://reviews.llvm.org/D58960
llvm-svn: 355821
When --compress-debug-sections is given, llvm-objcopy do not compress
sections that have "ZLIB" header in data. Normally this signature is used
in zlib-gnu compression format. But if zlib-gnu used then the name of the compressed
section should start from .z* (e.g .zdebug_info). If it does not, then it is not
a zlib-gnu format and section should be treated as a normal uncompressed section.
Differential revision: https://reviews.llvm.org/D58908
llvm-svn: 355399
Summary:
Include the symbol being defined in the list of requirements for using --localize-symbol.
This is used, for example, when someone is depending on two different projects that have the same (or close enough) method defined in each library, and using "-L sym" for a conflicting symbol in one of the libraries so that the definition from the other one is used. However, the library may have internal references to the symbol, which cause program crashes when those are used, i.e.:
```
$ cat foo.c
int foo() { return 5; }
$ cat bar.c
int foo();
int bar() { return 2 * foo(); }
$ cat foo2.c
int foo() { /* Safer implementation */ return 42; }
$ cat main.c
int bar();
int main() {
__builtin_printf("bar = %d\n", bar());
return 0;
}
$ ar rcs libfoo.a foo.o bar.o
$ ar rcs libfoo2.a foo2.o
# Picks the wrong foo() impl
$ clang main.o -lfoo -lfoo2 -L. -o main
# Picks the right foo() impl
$ objcopy -L foo libfoo.a && clang main.o -lfoo -lfoo2 -L. -o main
# Links somehow, but crashes at runtime
$ llvm-objcopy -L foo libfoo.a && clang main.o -lfoo -lfoo2 -L. -o main
```
Reviewers: jhenderson, alexshap, jakehehrlich, espindola
Subscribers: emaste, arichardson
Differential Revision: https://reviews.llvm.org/D57417
llvm-svn: 352767
Summary:
This adds support for the --discard-locals flag, which acts similarly to --discard-all, except it only applies to compiler-generated symbols (i.e. symbols starting with `.L` in ELF).
I am not sure about COFF local symbols: those appear to also use `.L` in most cases, but also use just `L` in other cases, so for now I am just leaving it unimplemented there.
Fixes PR36160
Reviewers: jhenderson, alexshap, jakehehrlich, mstorsjo, espindola
Reviewed By: jhenderson
Subscribers: llvm-commits, emaste, arichardson
Differential Revision: https://reviews.llvm.org/D57248
llvm-svn: 352626
Summary: Do some more error cleanup, removing some dependencies from llvm-objcopy's error/reportError in [ELF/COFF]Objcopy methods.
Reviewers: jhenderson, alexshap, jakehehrlich, mstorsjo, espindola
Subscribers: emaste, arichardson
Differential Revision: https://reviews.llvm.org/D57423
llvm-svn: 352625
Summary:
--set-section-flags is used to change the section flags (e.g. SHF_ALLOC) for given sections. The flags allowed are the same from the existing --rename-section=.old=.new[,flags] feature.
Additionally, make sure that --set-section-flag cannot be used with --rename-section (either the source or destination), since --rename-section accepts flags. This avoids ambiguity for something like "--rename-section=.foo=.bar,alloc --set-section-flag=.bar,code".
Reviewers: jhenderson, jakehehrlich, alexshap, espindola
Reviewed By: jhenderson, jakehehrlich
Subscribers: llvm-commits, emaste, arichardson
Differential Revision: https://reviews.llvm.org/D57198
llvm-svn: 352505
Summary:
This patch changes a few methods to return Error instead of manually calling error/reportError to abort. This will make it easier to extract into a library.
Note that error() takes just a string (this patch also adds an overload that takes an Error), while reportError() takes string + [error/code]. To help unify things, use FileError to associate a given filename with an error. Note that this takes some special care (for now), e.g. calling reportError(FileName, <something that could be FileError>) will duplicate the filename. The goal is to eventually remove reportError() and have every error associated with a file to be a FileError, and just one error handling block at the tool level.
This change was suggested in D56806. I took it a little further than suggested, but completely fixing llvm-objcopy will take a couple more patches. If this approach looks good, I'll commit this and apply similar patche(s) for the rest.
This change is NFC in terms of non-error related code, although the error message changes in one context.
Reviewers: alexshap, jhenderson, jakehehrlich, mstorsjo, espindola
Reviewed By: alexshap, jhenderson
Subscribers: llvm-commits, emaste, arichardson
Differential Revision: https://reviews.llvm.org/D56930
llvm-svn: 351896
This was requested in the review of D57006.
Also add missing quotes around symbol names in error messages.
Differential Revision: https://reviews.llvm.org/D57014
llvm-svn: 351799
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
Fix llvm-objcopy to add .note sections as SHT_NOTEs. GNU objcopy overrides section flags for special sections. For `.note` sections (with the exception of `.note.GNU-stack`), SHT_NOTE is used.
Many other sections are special cased by libbfd, but `.note` is the only special section I can seem to find being used with objcopy --add-section.
See `.note` in context of the full list of special sections here: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob;f=bfd/elf.c;h=eb3e1828e9c651678b95a1dcbc3b124783d1d2be;hb=HEAD#l2675
Reviewers: jhenderson, alexshap, jakehehrlich, espindola
Reviewed By: jhenderson
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D56570
llvm-svn: 351204
Summary:
The -O flag is currently being mostly ignored; it's only checked whether or not the output format is "binary". This adds support for a few formats (e.g. elf64-x86-64), so that when specified, the output can change between 32/64 bit and sizes/alignments are updated accordingly.
This fixes PR39135
Reviewers: jakehehrlich, jhenderson, alexshap, espindola
Reviewed By: jhenderson
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D53667
llvm-svn: 350541
Using an Error as an out parameter from an indirect operation like
iteration as described in the documentation (
http://llvm.org/docs/ProgrammersManual.html#building-fallible-iterators-and-iterator-ranges
) seems to be a little fussy - so here's /one/ possible solution, though
I'm not sure it's the right one.
Alternatively such APIs may be better off being switched to a standard
algorithm style, where they take a lambda to do the iteration work that
is then called back into (eg: "Error e = obj.for_each_note([](const
Note& N) { ... });"). This would be safer than having an unwritten
assumption that the user of such an iteration cannot return early from
the inside of the function - and must always exit through the gift
shop... I mean error checking. (even though it's guaranteed that if
you're mid-way through processing an iteration, it's not in an error
state).
Alternatively we'd need some other (the super untrustworthy/thing we've
generally tried to avoid) error handling primitive that actually clears
the error state entirely so it's safe to ignore.
Fleshed this solution out a bit further during review - it now relies on
op==/op!= comparison as the equivalent to "if (Err)" testing the Error.
So just like an Error must be checked (even if it's in a success state),
the Error hiding in the iterator must be checked after each increment
(including by comparison with another iterator - perhaps this could be
constrained to only checking if the iterator is compared to the end
iterator? Not sure it's too important).
So now even just creating the iterator and not incrementing it at all
should still assert because the Error has not been checked.
Reviewers: lhames, jakehehrlich
Differential Revision: https://reviews.llvm.org/D55235
llvm-svn: 348811
I just hard core goofed when I wrote this and created a different name
for no good reason. I'm failry aware of most "fresh" users of llvm-objcopy
(that is, users which are not using it as a drop in replacement for GNU
objcopy) and can say that only "-j" is being used by such people so this
patch should strictly increase compatibility and not remove it.
Differential Revision: https://reviews.llvm.org/D52180
llvm-svn: 348446
This flag does not exist in GNU objcopy but has a major use case.
Debugging tools support the .build-id directory structure to find
debug binaries. There is no easy way to build this structure up
however. One way to do it is by using llvm-readelf and some crazy
shell magic. This implements the feature directly. It is most often
the case that you'll want to strip a file and send the original to
the .build-id directory but if you just want to send a file to the
.build-id directory you can copy to /dev/null instead.
Differential Revision: https://reviews.llvm.org/D54384
llvm-svn: 348174
Summary: The original intention of !Config.xx.empty() was probably to emphasize the thing that is currently considered, but I feel the simplified form is actually easier to understand and it is also consistent with the call sites in other llvm components.
Reviewers: alexshap, rupprecht, jakehehrlich, jhenderson, espindola
Reviewed By: alexshap, rupprecht
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D55040
llvm-svn: 347891
Summary:
llvm-objcopy/strip support `--keep` (for sections) and `--keep-symbols` (for symbols). For consistency and clarity, rename `--keep` to `--keep-section`.
In fact, for GNU compatability, -K is --keep-symbol, so it's weird that the alias `-K` is not the same as the short-ish `--keep`.
Reviewers: jakehehrlich, jhenderson, alexshap, MaskRay, espindola
Reviewed By: jakehehrlich, MaskRay
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D54477
llvm-svn: 346782
Summary:
--localize-symbol and --localize-hidden will currently localize common symbols. GNU objcopy will not localize these symbols even when explicitly requested, which seems reasonable; common symbols should always be global so they can be merged during linking.
See PR39461
Reviewers: jakehehrlich, jhenderson, alexshap, MaskRay, espindola
Reviewed By: jakehehrlich, jhenderson, alexshap, MaskRay
Subscribers: emaste, arichardson, alexshap, MaskRay, llvm-commits
Differential Revision: https://reviews.llvm.org/D53782
llvm-svn: 345856
Summary: --keep-global-symbol and --globalize-symbol don't make sense for undefined symbols, so it should be ignored for those symbols. This matches GNU objcopy behavior.
Reviewers: jhenderson, alexshap, jakehehrlich, espindola
Reviewed By: jhenderson, jakehehrlich
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D53733
llvm-svn: 345614
In this diff the elf-specific code is moved into the subfolder ELF
(and factored out from llvm-objcopy.cpp).
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D53790
llvm-svn: 345544
James Henderson