Commit Graph

470 Commits

Author SHA1 Message Date
Rui Ueyama 24a47201fd Merge LazyArchive::fetch() and ArchiveFile::getMember(). NFC.
They are to pull out an object file for a symbol, but for a historical
reason the code is written in two separate functions. This patch
merges them.

llvm-svn: 329039
2018-04-03 02:06:57 +00:00
Rafael Espindola c8f774b393 Strip @VER suffices from the LTO output.
This fixes pr36623.

The problem is that we have to parse versions out of names before LTO
so that LTO can use that information.

When we get the LTO produced .o files, we replace the previous symbols
with the LTO produced ones, but they still have @ in their names.

We could just trim the name directly, but calling parseSymbolVersion
to do it is simpler.

llvm-svn: 328738
2018-03-28 22:45:39 +00:00
Rui Ueyama 048a669b92 allow-multiple-definitions should completely suppress errors instead of making them warnings.
We found that when you pass --allow-multiple-definitions or `-z muldefs`
to GNU linkers, they don't complain about duplicate symbols at all. They
don't even print out warnings on it. We emit warnings in that case.
If you pass --fatal-warnings, that difference results in a link failure.

Differential Revision: https://reviews.llvm.org/D44549

llvm-svn: 327920
2018-03-19 23:04:04 +00:00
Rafael Espindola ddb33c0961 Improve duplicated version handling.
It looks like the problem that caused us to originally warn instead of
error was that of a symbol being assigned to the same version twice.

Now we don't warn if a symbol is assigned to the same version twice,
but error if it is assigned to multiple.

This fixes pr28342.

llvm-svn: 326813
2018-03-06 17:05:12 +00:00
Rafael Espindola e3a6062844 Simplify. NFC.
Since r321982 we don't set VersionId in scanShlibUndefined, which
makes InVersionScript redundant.

llvm-svn: 326641
2018-03-03 02:13:50 +00:00
Rafael Espindola 3f4c673d38 Put undefined symbols from shared libraries in the symbol table.
With the recent fixes these symbols have more in common than not with
regular undefined symbols.

llvm-svn: 326242
2018-02-27 20:31:22 +00:00
Igor Kudrin 3345c9ac18 [ELF] Create and export symbols provided by a linker script if they referenced by DSOs.
It should be possible to resolve undefined symbols in dynamic libraries
using symbols defined in a linker script.

Differential Revision: https://reviews.llvm.org/D43011

llvm-svn: 326176
2018-02-27 07:18:07 +00:00
Rui Ueyama c30927411c Make undefined symbol in DSO to pull out object files from archive files.
We have an internal program that does't link without this patch. I don't
know of any open-source program that needs this, but there might be.
Since this patch improves compatibility with GNU linkers with a few lines
of code, I think it's worth to be committed.

The problem is about undefined symbols in DSOs. Some programs depend on
the GNU linkers' behavior that they pull out object files from archive
files to resolve undefined symbols in DSOs. We already allow that kind of
"reverse" dependency (from DSOs to the main executable) for regular
symbols, in particular, for "__progname" symbol (which is usually in
crt0.o), but that doesn't work if the symbol is in an archive file.
This patch is to make it work.

Differential Revision: https://reviews.llvm.org/D43658

llvm-svn: 325849
2018-02-23 01:16:57 +00:00
Peter Collingbourne 09e04af42f ELF: Stop collecting a list of symbols in ArchiveFile.
There seems to be no reason to collect this list of symbols.

Also fix a bug where --exclude-libs would apply to all symbols that
appear in an archive's symbol table, even if the relevant archive
member was not added to the link.

Differential Revision: https://reviews.llvm.org/D43369

llvm-svn: 325380
2018-02-16 20:23:54 +00:00
Rui Ueyama 6de1e858a1 Fix an issue that weak bit is dropped when there's a lazy object symbol.
Previously, we accidentally dropped STB_WEAK bit from an undefined symbol
if there is a lazy object symbol with the same name. That caused a
compatibility issue with GNU gold.

llvm-svn: 325316
2018-02-16 04:27:46 +00:00
Rui Ueyama af7242a385 Use reinterpret_cast<> instead of C-style cast. NFC.
It is currently interpreted as reinterpret_cast<>. Make it explicit.

Differential Revision: https://reviews.llvm.org/D43247

llvm-svn: 325033
2018-02-13 18:11:42 +00:00
Rui Ueyama aad2e328b9 Add --no-gnu-unique and --no-undefined-version for completeness.
Differential Revision: https://reviews.llvm.org/D42865

llvm-svn: 324145
2018-02-02 21:44:06 +00:00
George Rimar fd5a33d623 [ELF] - Do not forget file name when reporting duplicate symbol error for absolute symbols.
When there is a duplicate absolute symbol, LLD reports <internal>
instead of known object file name currently.
Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D42636

llvm-svn: 323849
2018-01-31 08:32:35 +00:00
Rafael Espindola 8e2fc4f3f8 Don't mark a shared library as needed because of a lazy symbol.
Fixes PR36029.

llvm-svn: 323221
2018-01-23 16:59:20 +00:00
Rafael Espindola 7e6aeb614c Fix another case we used the wrong visibility.
In here too we want the computed output visibility.

llvm-svn: 322586
2018-01-16 19:02:46 +00:00
Easwaran Raman bfa48a14ab [ELF] Explicit template instantiations for addFile
Summary:
All other templated methods have explicit instantiations but this one is
missing. Discovered while building with a clang with inliner
modifications.

Reviewers: espindola

Subscribers: emaste, llvm-commits, davidxl

Differential Revision: https://reviews.llvm.org/D41847

llvm-svn: 322057
2018-01-09 05:35:29 +00:00
Shoaib Meenai c1ca8065b5 [ELF] Small grammar fix. NFC
The whole consists of the parts, not the other way around.

llvm-svn: 322042
2018-01-08 23:18:16 +00:00
Shoaib Meenai 3a15fb591e [ELF] Drop unnecessary VersionId setting in scanShlibUndefined
LLD previously used to handle dynamic lists and version scripts in the
exact same way, even though they have very different semantics for
shared libraries and subtly different semantics for executables. r315114
untangled their semantics for executables (building on previous work to
correct their semantics for shared libraries). With that change, dynamic
lists won't set the default version to VER_NDX_LOCAL, and so resetting
the version to VER_NDX_GLOBAL in scanShlibUndefined is unnecessary.

This was causing an issue because version scripts containing `local: *`
work by setting the default version to VER_NDX_LOCAL, but scanShlibUndefined
would override this default, and therefore symbols which should have
been local would end up in the dynamic symbol table, which differs from
both bfd and gold's behavior. gold silently keeps the symbol hidden in
such a scenario, whereas bfd issues an error. I prefer bfd's behavior
and plan to implement that in LLD in a follow-up (and the test case
added here will be updated accordingly).

Differential Revision: https://reviews.llvm.org/D41639

llvm-svn: 321982
2018-01-08 05:53:11 +00:00
Rafael Espindola 9a84f6b954 Detemplate reportDuplicate.
We normally avoid "switch (Config->EKind)", but in this case I think
it is worth it.

It is only executed when there is an error and it allows detemplating
a lot of code.

llvm-svn: 321404
2017-12-23 17:21:39 +00:00
Rafael Espindola 9f37543cf8 Detemplate isCompatible(). NFC.
llvm-svn: 321393
2017-12-23 00:04:34 +00:00
Rafael Espindola 8276f1bda6 Use a reference to a file in the LazyArchive symbol.
It is never null.

llvm-svn: 321198
2017-12-20 17:59:43 +00:00
Rafael Espindola 2e5c71eadc LazyObject's file is never null, use a reference.
llvm-svn: 321196
2017-12-20 17:52:36 +00:00
Rafael Espindola 8cd6674f5b Use a reference in addLazyArchive. NFC.
llvm-svn: 321194
2017-12-20 17:48:28 +00:00
Rafael Espindola a32ddc4639 Use a reference for the shared symbol file.
Every shared symbol has a file, so we can use a reference.

llvm-svn: 321187
2017-12-20 16:28:19 +00:00
Rafael Espindola 7b5cc6c5dc Use a reference for a value that is never null. NFC.
llvm-svn: 321186
2017-12-20 16:19:48 +00:00
Rafael Espindola f1687125ba Use a reference for a value that is never null. NFC.
llvm-svn: 321185
2017-12-20 16:16:40 +00:00
Rafael Espindola 092ba58bee Replace a dyn_cast_or_null with dyn_cast.
The variable being casted was accessed in the previous line.

llvm-svn: 321140
2017-12-20 01:57:19 +00:00
Rui Ueyama fbe68a3584 Use warn() instead of error() to report a bad symbol in a DSO.
Specifically, libwidevinecdm.so in Chrome has such bad symbol.
It seems the BFD linker handles them as local symbols, so instead
of inserting them to the symbol table, we should skip them too.

Differential Revision: https://reviews.llvm.org/D41257

llvm-svn: 320770
2017-12-15 00:01:33 +00:00
Rafael Espindola b308cace84 Fix crash on invalid.
We would fail an assert if a shared library had a local symbol after
sh_info.

llvm-svn: 320667
2017-12-14 05:01:49 +00:00
Rafael Espindola 8f619ab826 Compact symbols from 96 to 88 bytes.
By using an index instead of a pointer for verdef we can put the index
next to the alignment field. This uses the otherwise wasted area and
reduces the shared symbol size.

By itself the performance change of this is in the noise, but I have a
followup patch to remove another 8 bytes that improves performance
when combined with this.

llvm-svn: 320449
2017-12-12 01:45:49 +00:00
Evgeniy Stepanov 9ac3154d10 [lld] Fix handling of wildcards in dynamic lists.
Reviewers: pcc, ruiu

Subscribers: llvm-commits, emaste

Differential Revision: https://reviews.llvm.org/D40868

llvm-svn: 319860
2017-12-06 00:14:04 +00:00
Rafael Espindola b2ee25ac8a Simplify. NFC.
This particular reportDuplicate is only used with Defined.

llvm-svn: 319451
2017-11-30 18:02:04 +00:00
Rafael Espindola dfebd3601d Use Symbol::File directly.
We are already paying the cost of storing a InputFile in every
Symbol, so use it uniformly.

llvm-svn: 319378
2017-11-29 22:47:35 +00:00
Rafael Espindola b262cbe6b7 Replace copyFrom with memcpy.
It was only used for --wrap and I don't think the fields with special
treatment had a meaningful impact on that feature.

llvm-svn: 319265
2017-11-29 00:31:39 +00:00
Rui Ueyama 2017d52b54 Move Memory.{h,cpp} to Common.
Differential Revision: https://reviews.llvm.org/D40571

llvm-svn: 319221
2017-11-28 20:39:17 +00:00
Rafael Espindola 1d4b3023dc Bring back r319008.
This includes a fix to mark copy reloc aliases as used.

Original message:

[ELF] Do not keep symbols if they referenced only from discarded sections.

This patch also ensures that in case of "--as-needed" is used,
DT_NEEDED entries are not created if they are required only by
these eliminated symbols.

llvm-svn: 319215
2017-11-28 20:17:58 +00:00
Igor Kudrin a46522f369 Revert r319008, "[ELF] Do not keep symbols if they referenced only from discarded sections."
and r319051, "Add a missing test."

r319008 broke the LTO bots;
r319051 depends on changes in r319008.

llvm-svn: 319154
2017-11-28 08:39:40 +00:00
Rui Ueyama 53fe469162 Factor out common code to Common/Strings.cpp.
Differential Revision: https://reviews.llvm.org/D40530

llvm-svn: 319138
2017-11-28 02:15:26 +00:00
Rafael Espindola 9e3381e8dc Store the real binding of shared symbols.
Currently we mark every shared symbol as STB_WEAK.

That is a hack to make it easy to decide when a .so is needed or not
because of a reference to a given symbol.

That hack leaks when we create copy relocations as shown by the update
to relocation-copy-alias.s.

This patch stores the original binding when we first read a shared
symbol. We still have to update the binding to weak if we see a weak
undef, but I find the logic easier to read where it is now.

llvm-svn: 319127
2017-11-28 01:04:51 +00:00
Sam Clegg a80d94d52b Rename `Symtab` private memory to avoid confusion with global `Symtab`
This is also consistent with SymVector that exists in COFF port
and soon to be added to the wasm port.

Split off as part of https://reviews.llvm.org/D40371

Differential Revision: https://reviews.llvm.org/D40525

llvm-svn: 319113
2017-11-27 23:16:06 +00:00
Igor Kudrin 40007586fc [ELF] Do not keep symbols if they referenced only from discarded sections.
This patch also ensures that in case of "--as-needed" is used,
DT_NEEDED entries are not created if they are required only by
these eliminated symbols.

Differential Revision: https://reviews.llvm.org/D38790

llvm-svn: 319008
2017-11-27 05:51:10 +00:00
Rafael Espindola de56343cf0 Simplify as-needed handling.
This is a reduction of a patch by Rui Ueyama.

llvm-svn: 318852
2017-11-22 17:50:42 +00:00
Rafael Espindola bec3765bea Remove IsLocal.
Since we always have Binding in the current symbol design IsLocal is
redundant.

llvm-svn: 318497
2017-11-17 01:37:50 +00:00
Rafael Espindola 99f9e1373b Simplify. NFC.
copyFrom doesn't copy the Binding, so this was a nop.

llvm-svn: 317965
2017-11-11 01:59:47 +00:00
Rafael Espindola 5c22661255 Don't produce a duplicated __wrap_foo if there is no __real_foo.
This fixes a regression from r317426.

llvm-svn: 317956
2017-11-11 00:53:52 +00:00
Peter Collingbourne 38082ac62d ELF: Remove SymbolTable::SymIndex class.
The Traced flag is unnecessary because we only need to set the index
to -1 to mark a symbol for tracing.

Differential Revision: https://reviews.llvm.org/D39672

llvm-svn: 317450
2017-11-06 04:58:04 +00:00
Peter Collingbourne b472aa0268 ELF: Remove function Symbol::isInCurrentOutput().
This function is now equivalent to isDefined().

llvm-svn: 317449
2017-11-06 04:39:07 +00:00
Peter Collingbourne e9a9e0a1e7 ELF: Merge DefinedRegular and Defined.
Now that DefinedRegular is the only remaining derived class of
Defined, we can merge the two classes.

Differential Revision: https://reviews.llvm.org/D39667

llvm-svn: 317448
2017-11-06 04:35:31 +00:00
Peter Collingbourne 6c55a70838 ELF: Remove DefinedCommon.
Common symbols are now represented with a DefinedRegular that points
to a BssSection, even during symbol resolution.

Differential Revision: https://reviews.llvm.org/D39666

llvm-svn: 317447
2017-11-06 04:33:58 +00:00
Rui Ueyama dc0b0b0df3 Rewrite addSymbolWrap and applySymbolWrap. NFCI.
r317396 changed the way how we handle the -defsym option. The option is
now handled using the infrastructure for the linker script.

We used to handle both -defsym and -wrap using the same set of functions
in the symbol table. Now, we don't need to do that.

This patch rewrites the functions so that they become more straightforward.
The new functions directly handle -wrap rather than abstract it.

llvm-svn: 317426
2017-11-04 23:09:43 +00:00