We have a few "check" functions in Error.h. All of them are to
check for an error and strip an error object if there was no error,
except "void check(Error E)", which doesn't return anything.
This patch renames it and moves it to the .cpp file where it is used.
llvm-svn: 282764
If there is not sufficient address space, just give up and don't put
the header in the PT_LOAD.
This matches bfd behaviour and I found at least one script that
depends on having a section at address 0.
llvm-svn: 282750
LLD does not update relocations addends when generate a relocatable
object. That is why we should not write a non-zero GP0 value into
the .reginfo and .MIPS.options sections. And we should not accept input
object files with non-zero GP0 value because we cannot handle them
properly.
llvm-svn: 282716
In case of linking PIC and non-PIC code together and generation of a
relocatable object, all PIC symbols should have STO_MIPS_PIC flag in the
symbol table of the ouput file.
llvm-svn: 282714
If we two sections reside in the same PT_LOAD segment,
we compute second section using the following formula:
Off2 = Off1 + VA2 - VA1. This allows OS kernel allocating
sections correctly when loading an image.
Differential revision: https://reviews.llvm.org/D25014
llvm-svn: 282705
This matches the behavior of Binutils linkers. We also change the
default MaxPageSize on x86-64 to 0x1000 to preserver the current
behavior, which is the same as the behavior implemented by gold.
https://llvm.org/bugs/show_bug.cgi?id=30541
Differential Revision: https://reviews.llvm.org/D24987
llvm-svn: 282560
r282444 introduced new issue, sample program below
fails to link on
assert(Piece.Live);
int main() { return 0; }
clang test.cpp -c -o out.o -g
ld.lld -flavor gnu --gc-sections out.o -o out
Problem is that .debug_info contains relocations to .debug_str:
Section (7) .rela.debug_info {
..
0xC R_X86_64_32 .debug_str 0x0
0x12 R_X86_64_32 .debug_str 0x37
..
But we do not preserve .debug_str in a right way now.
To fix this we should ignore relocations from non-allocatable sections to allocatable
to allow GC work at full power, but still should proccess relocations from non-allocatable to non-allocatable sections
as usual to mark some parts of debug sections alive to keep them so we do not end
up with such assert when trying to access dead pieces. That looks like what gold/ld do, they do
not strip .debug_str section from what I saw using sample provided.
Thanks to Evgeny Leviant for suggestions about how to fix this.
Differential revision: https://reviews.llvm.org/D24967
llvm-svn: 282495
The BYTE, SHORT, LONG, and QUAD commands store one, two, four, and eight bytes (respectively).
After storing the bytes, the location counter is incremented by the number of bytes
stored.
Previously our scripts handles these commands incorrectly. For example:
SECTIONS {
.foo : {
*(.foo.1)
BYTE(0x11)
...
We accepted the script above treating BYTE as input section description.
These commands are used in the wild though.
Differential revision: https://reviews.llvm.org/D24830
llvm-svn: 282429
PR30521 was about linking shared library. After r282295 code when linking -shared produced
"entry symbol not found" warning, what in combination with --fatal-errors failed linkage.
Patch fixes logic (and adds testcases) to follow next rules:
1) If entry was specified and not found report warning.
2) If entry was not specified then:
a) Emit warning if not -shared.
b) Do not emit warning if -shared.
Differential revision: https://reviews.llvm.org/D24913
llvm-svn: 282427
I found out this wasn't tested when looking at Vedant's coverage bot
numbers, so, thanks to him. While I'm here, switch the error message
to be lld-compliant (first letter lowercase).
llvm-svn: 282335
We were counting the size of the bss section holding common symbols twice:
Dot += CurOutSec->getSize();
flush();
The new code is also simpler as now flush is the only function that
inserts in AlreadyOutputOS, which makes sense since the set hold fully
output sections.
llvm-svn: 282285
If we pass --gc-sections to lld and .tbss is not referenced,
the section is reclaimed and lld doesn't create a TLS program header.
R_TLS tries to access the program header -> lld crashes.
Mimic what bfd/gold do in this case and resolve a weak undefined
TLS symbol to the base of the TLS block, i.e. give it a value of zero.
Differential Revision: https://reviews.llvm.org/D24832
llvm-svn: 282279
The ARM TLS relocations are placed on literal data and not the
code-sequence, it is therefore not possible to implement the relaxTls*
functions. This change updates handleMipsTlsRelocation() to
handleNoRelaxTlsRelocation() and incorporates ARM as well as Mips.
The ARM support in handleNoRelaxTlsRelocation() currently needs to ouput
the module index dynamic relocation in all cases as it is relying on the
dynamic linker to set the module index in the got.
Should address PR30218
Differential Revision: https://reviews.llvm.org/D24827
llvm-svn: 282250
Previously we failed to parse next scripts because disallowed
a space between filler value and '=':
.text : {
...
} :text = 0x9090
Differential revision: https://reviews.llvm.org/D24831
llvm-svn: 282248
DEFINED(symbol)
Return 1 if symbol is in the linker global symbol table and is defined before
the statement using DEFINED in the script, otherwise return 0.
Can be used to define default values for symbols. Found it in the wild.
Differential revision: https://reviews.llvm.org/D24858
llvm-svn: 282245
If section contains local symbols ldd crashes, because local
symbols are added to symbol table before section is discarded
by linker script processor. This patch calls copyLocalSymbols()
after createSections, so discarded section symbols are not copied
llvm-svn: 282244
Found this operators used in the wild scripts, for example:
__got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >>2;
__fixup_entries = (. - _FIXUP_TABLE_)>>2;
Differential revision: https://reviews.llvm.org/D24860
llvm-svn: 282243
The ELF spec doesn't allow relocations to point directly to
a deduplicated COMDAT section but this unfortunately happens in
practice. Bail out early instead of crashing.
Differential Revision: https://reviews.llvm.org/D24750
llvm-svn: 282197
With the recent changes there should always be a 1:1 correspondence in
the correct order between OutputSections and OutputSectionCommands.
llvm-svn: 282176
The actual logic is to keep the output section if the output section
would have been ro/rw.
This is both simpler and more practical, as the intention is linker
scripts is to always keep of of a pair of ONLY_IF_RO/ONLY_IF_RW.
llvm-svn: 282099
This is PR30442.
Previously we were failed to parce complex expressions like:
foo : { *(SORT_BY_NAME(bar) zed) }
Main idea of patch that globs and excludes can be wrapped in a SORT.
There is a difference in semanics of ld/gold:
ld likes:
*(SORT(EXCLUDE_FILE (*file1.o) .foo.1))
gold likes:
*(EXCLUDE_FILE (*file1.o) SORT(.foo.1))
Patch implements ld grammar, complex expressions like
next is not a problem anymore:
.abc : { *(SORT(.foo.* EXCLUDE_FILE (*file1.o) .bar.*) .bar.*) }
Differential revision: https://reviews.llvm.org/D24758
llvm-svn: 282078
When final image has several .bss sections, lld fails
because second .bss always has zero VA. This causes
link error "Not enough space for ELF and program headers"
llvm-svn: 282067
It is not only a bit more straightforward now, but also next 2 issues are solved:
* It just crashed on ".foo : { *(EXCLUDE_FILE (*file1.o)) }" before.
* It accepted multiple EXCLUDE_FILEs in a row.
Differential revision: https://reviews.llvm.org/D24726
llvm-svn: 282060
This surfaced again with Rust. As per bug 30435, rustc creates a
mergeable section with a sh_entsize zero. It bit us before, too.
I think we should relax the input check rather than being too picky.
Differential Revision: https://reviews.llvm.org/D24789
llvm-svn: 282049
This reverts commit r282021, bringing back r282015.
The problem was that the comparison function was not a strict weak
ordering anymore, which this patch fixes.
Original message:
Only restrict order if both sections are in the script.
This matches gold and bfd behavior and is required to handle some scripts.
The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.
llvm-svn: 282035
This matches gold and bfd behavior and is required to handle some scripts.
The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.
llvm-svn: 282015
This is particularly important when the symbol comes from a linker
script. It is common to use the same linker script for shared
libraries and executables. Without this we would always fail to link
shared libraries with -z,defs and a linker script with an ENTRY
directive.
llvm-svn: 281989
Linker scripts are responsible for aliging '.'. Since they are
designed for bfd which has no --rosegment, they don't align the RO to
RX transition.
llvm-svn: 281978
InputSection<ELFT>::Discarded has no name and it's not backed by
a file. Trying to report it as discared will cause a nullptr
dereference, therefore a crash. Skip it.
Differential Revision: https://reviews.llvm.org/D24731
llvm-svn: 281946
The InputSection variables in the Writer were named `C`. This
was because when the ELF linker was ported (from COFF)
the name `Chunks` for input sections was retained.
Luckily we switched to a more ELF-compliant jargon, but these
variables weren't reanamed accordingly during the transition.
llvm-svn: 281917
Will Dietz found and reported that lld does not compile with gcc 6.2.0,
more details https://llvm.org/bugs/show_bug.cgi?id=30438
And confirmed this change fixes the issue.
llvm-svn: 281900
Our implementation supported integer value previously.
ld can use expression,
for example, it is OK to write
. = SEGMENT_START("foobar", .);
Patch implements that.
llvm-svn: 281831
It was possible situation about some commands just were not processed
(were skipped) because of a bug appeared when constraint checking used.
Testcase is attached.
llvm-svn: 281818
This matches gold and bfd, and is pretty much required by some linker
scripts. They end with commands like
foo 0 : { *(bar) }
if we put any SHF_ALLOC sections after they can have an address that
is too low.
llvm-svn: 281778
This matches bfd behavior. It also makes future changes simpler as we
don't have to worry about ignoring these commands in multiple places
llvm-svn: 281775
With fix for 2 bots. Details about the fix performed is on a review page.
Initial commit message:
This is PR30387:
From PR description:
We fail to parse
SECTIONS
{
foo :
{
*(sec0 EXCLUDE_FILE (zed1.o) sec1 EXCLUDE_FILE (zed2.o) sec2 )
}
}
The semantics according to bfd are:
Include sec1 from every file but zed1.o
Include sec2 from every file but zed2.o
Include sec0 from every file
Patch implements the support.
Differential revision: https://reviews.llvm.org/D24650
llvm-svn: 281754
This fixes pr30367, but more importantly, it changes how we compute offsets.
Now offset computation in a walk over linker script commands, like the
rest of assignAddresses. IMHO this is simpler to understand and if we
ever have to create multiple outputsections or chunks to change how we
handle test/ELF/linkerscript/alternate-sections.s it should be easier
to do it.
llvm-svn: 281736
This is PR30387:
From PR description:
We fail to parse
SECTIONS
{
foo :
{
*(sec0 EXCLUDE_FILE (zed1.o) sec1 EXCLUDE_FILE (zed2.o) sec2 )
}
}
The semantics according to bfd are:
Include sec1 from every file but zed1.o
Include sec2 from every file but zed2.o
Include sec0 from every file
Patch implements the support.
Differential revision: https://reviews.llvm.org/D24650
llvm-svn: 281721
This is PR30386,
SORT_BY_INIT_PRIORITY is a keyword can be used to sort sections by numerical value of the
GCC init_priority attribute encoded in the section name.
Differential revision: https://reviews.llvm.org/D24611
llvm-svn: 281646
Previouly bot was failing:
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/413/steps/test-stage1-compiler/logs/stdio
Fixed possible segfault, so commit should bix the buildbot.
Initial commit message:
This is PR30312. Info from bug page:
Both of these symbols demangle to abc::abc():
_ZN3abcC1Ev
_ZN3abcC2Ev
(These would be abc's complete object constructor and base object constructor, respectively.)
however with "abc::abc()" in the version script only one of the two receives the symbol version.
Patch fixes that.
It uses testcase created by Ed Maste (D24306).
Differential revision: https://reviews.llvm.org/D24336
llvm-svn: 281605
--section-start=sectionname=org
Locate a section in the output file at the absolute address given by org.
You may use this option as many times as necessary to locate multiple sections in the command line.
org must be a single hexadecimal integer; for compatibility with other linkers,
you may omit the leading `0x' usually associated with hexadecimal values.
Note: there should be no white space between sectionname, the equals sign (“<=>”), and org.
-Tbss=org
-Tdata=org
-Ttext=org
Same as --section-start, with .bss, .data or .text as the sectionname.
Differential revision: https://reviews.llvm.org/D24294
llvm-svn: 281458
Previously, all input files were owned by the symbol table.
Files were created at various places, such as the Driver, the lazy
symbols, or the bitcode compiler, and the ownership of new files
was transferred to the symbol table using std::unique_ptr.
All input files were then free'd when the symbol table is freed
which is on program exit.
I think we don't have to transfer ownership just to free all
instance at once on exit.
In this patch, all instances are automatically collected to a
vector and freed on exit. In this way, we no longer have to
use std::unique_ptr.
Differential Revision: https://reviews.llvm.org/D24493
llvm-svn: 281425
Something broked BBots:
281318 failed on step 9:
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/413
r281317 built step 9 green:
http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/415
Initial revision commits were:
This is PR30312. Info from bug page:
Both of these symbols demangle to abc::abc():
_ZN3abcC1Ev
_ZN3abcC2Ev
(These would be abc's complete object constructor and base object constructor, respectively.)
however with "abc::abc()" in the version script only one of the two receives the symbol version.
Patch fixes that.
It uses testcase created by Ed Maste (D24306).
Differential revision: https://reviews.llvm.org/D24336
llvm-svn: 281411
Without this flag set, an AArch64 Linux kernel won't try to load the executable
(even if a 32 bit arm kernel will run the binary just fine).
Patch by Martin Storsjö!
Differential revision: https://reviews.llvm.org/D24471
llvm-svn: 281394
This is PR30312. Info from bug page:
Both of these symbols demangle to abc::abc():
_ZN3abcC1Ev
_ZN3abcC2Ev
(These would be abc's complete object constructor and base object constructor, respectively.)
however with "abc::abc()" in the version script only one of the two receives the symbol version.
Patch fixes that.
It uses testcase created by Ed Maste (D24306).
Differential revision: https://reviews.llvm.org/D24336
llvm-svn: 281318
Implemented by building an ELF file in memory.
elf, default, and binary match gold behavior.
Differential Revision: https://reviews.llvm.org/D24060
llvm-svn: 281108
Fixed code that was not checked before on windows for me, because of testcases that are
disabled on that platform atm.
Inital commit message:
"[ELF] - Versionscript: do not treat non-wildcarded names as wildcards."
Previously we incorrectly handled cases when symbol name in extern c++ tag
was enclosed in quotes. Next case was treated as wildcard:
GLIBCXX_3.4 {
extern "C++" {
"aaa*"
}
But it should have not. Quotes around aaa here means that we should have do exact
name matching.
That is PR30268 which has name with pointer is interpreted as wildcard by lld:
extern "C++" {
"operator delete[](void*)";
Patch fixes the issue.
Differential revision: https://reviews.llvm.org/D24229
llvm-svn: 281049
Fixed code that was not checked by testcases that are disabled on windows.
Inital commit message:
"[ELF] - Versionscript: do not treat non-wildcarded names as wildcards."
Previously we incorrectly handled cases when symbol name in extern c++ tag
was enclosed in quotes. Next case was treated as wildcard:
GLIBCXX_3.4 {
extern "C++" {
"aaa*"
}
But it should have not. Quotes around aaa here means that we should have do exact
name matching.
That is PR30268 which has name with pointer is interpreted as wildcard by lld:
extern "C++" {
"operator delete[](void*)";
Patch fixes the issue.
Differential revision: https://reviews.llvm.org/D24229
llvm-svn: 281045
Previously we incorrectly handled cases when symbol name in extern c++ tag
was enclosed in quotes. Next case was treated as wildcard:
GLIBCXX_3.4 {
extern "C++" {
"aaa*"
}
But it should have not. Quotes around aaa here means that we should have do exact
name matching.
That is PR30268 which has name with pointer is interpreted as wildcard by lld:
extern "C++" {
"operator delete[](void*)";
Patch fixes the issue.
Differential revision: https://reviews.llvm.org/D24229
llvm-svn: 281038
Usually, options that are longer than one character can be preceded
either by "-" or "--", but options starting with "o" are exceptions
because they conflict with "-o" option. They have to be preceded by
"--".
llvm-svn: 281004
We still have to skip a token inside SEARCH_DIR() when -nostdlib is
specified. Previuosly, we didn't skip it, so it caused a parse error.
llvm-svn: 281001
lld differs from GNU ld in that it does not have a built-in default
target emulation. Emulation is always specified via the -m option, or
obtained from the object file(s) being linked. In most cases at least
one ELF object is included in the link, so the emulation is known.
When using lld's (not yet committed) -b binary support with -r, to
convert a binary file into an ELF object we do not have a known
emulation. The error message previously emitted in this case
"-m or at least a .o file required" is accurate but does not offer
much insight. Add text to the error message to give a hint why -m or an
object file is required.
Differential Revision: https://reviews.llvm.org/D24348
llvm-svn: 280989
A trailing _fbsd is stripped from emulation names, but if the result was
still not a valid emulation the error was somewhat confusing.
For example,
% ld.lld -m elf_amd64_fbsd
unknown emulation: elf_amd64
Use the original emulation name in error messages.
Differential Revision: https://reviews.llvm.org/D24357
llvm-svn: 280983
In the FreeBSD world x86_64 still has its original name, amd64. Accept
it as an alias.
Differential Revision: https://reviews.llvm.org/D24356
llvm-svn: 280982
This simplifies error handling as there is now only one place in the
code that needs to consider the possibility that the name is
corrupted. Before we would do it in every access.
llvm-svn: 280937
Absence of it caused a clang warning:
warning: 'lld:🧝:LinkerScriptBase' has virtual functions but non-virtual destructor [-Wnon-virtual-dtor]
At fact we don't need it here because do not destroy this object by
base pointer.
llvm-svn: 280916
This patch allows static linking of TLS code. To do that it fixes
GOT entries initialization.
If TLS-related GOT entry created for a preemptible symbol i.e. has
a corresponding dynamic relocation, leave the entry initialized by zero.
Write down adjusted TLS symbol's values otherwise. For the adjustments
calculation use offsets for thread-local storage.
https://www.linux-mips.org/wiki/NPTL
llvm-svn: 280914
Previous way of accessing templated methods was a bit bulky,
Patch introduces small interface based solution.
Differential revision: https://reviews.llvm.org/D23872
llvm-svn: 280910
GCC passes it by default on powerpc64 on FreeBSD. GNU ld claims "this
option is ignored for SVR4 compatibility", so we can ignore it too.
Differential Revision: https://reviews.llvm.org/D24313
llvm-svn: 280864
Previously we combined sections by name if linkerscript was used.
For that we had to disable SHF_MERGE handling temporarily, but then
found that implementing it properly will require additional complexity layers like
subsections or something.
At the same time looks we can live with multiple output sections approach for now.
That patch do this change.
Differential revision: https://reviews.llvm.org/D24127
llvm-svn: 280801
GNU ld supports [chars] wildcards in version scripts, to match a single instance of any of the chars.
Here is an extern example from libstdc++'s version script in FreeBSD:
extern "C++"
{
...
std::locale::_[T-Za-z]*;
std::[A-Zm]*;
std::n[^u]*;
std::nu[^m]*;
std::num[^e]*;
...
}
Patch adds support for scripts above. This is PR29093.
Differential revision: https://reviews.llvm.org/D23803
llvm-svn: 280799
This flag is supported by both BFD ld and gold and is occasionally
used to negate the effect of -gc-sections flag.
Differential Revision: https://reviews.llvm.org/D24270
llvm-svn: 280729
Patch implements FILL just as alias for =fillexpr.
This allows to make implementation much shorted and simpler than D24186.
Differential revision: https://reviews.llvm.org/D24227
llvm-svn: 280708
On most architectures the linker is required to optimize away any
references to __tls_get_addr in case of static linking. As usual
a special case is MIPS - libc defines __tls_get_addr itself because
there are no TLS optimizations for this architecture.
llvm-svn: 280664
It looks like MIPS dynamic loader does not support RELCOUNT tag.
Both gold/bfd linkers does not emit this tag on MIPS. I will investigate
the problem further but for now it is better to behave like GNU linkers.
llvm-svn: 280630
Use std::regex instead of hand written matcher.
Patch based on code and ideas of Rui Ueyama.
Differential revision: https://reviews.llvm.org/D23829
llvm-svn: 280544
"Error" looks like it is indicating a parse error. "Error" actually
instructs the later process to report an error if there's an error
condition. Thus the new name.
llvm-svn: 280529
Cmd used to be the single central place to dispatch. It is not longer
the case because we have a logic for readProvideOrAssignment().
This patch removes the hash table so that evrything is in a single
function. This is slightly verbose but should improve readability.
Differential Revision: https://reviews.llvm.org/D24200
llvm-svn: 280524
Both bfd and gold accept:
foo = 1K;
bar = 1M;
zed = 1H;
And lowercase forms: k, m, h.
Patch adds support for that.
Differential revision: https://reviews.llvm.org/D24194
llvm-svn: 280494
FreeBSD's libstdc++ build (used on tier-2 architectures) uses GNU ld's
-f <name> option, which sets the DT_AUXILIARY field to the specified name.
Multiple -f options may be specified and the DT_AUXILIARY entries
will be added in the order in which they appear.
Patch implements that option.
Differential revision: https://reviews.llvm.org/D24139
llvm-svn: 280475
The primary use of build-id is in debugging, hence omitting debug
sections when computing it significantly reduces its usability as
changes in debug section content wouldn't alter the build-id.
Differential Revision: https://reviews.llvm.org/D24120
llvm-svn: 280421
This is what InputSectionBase<ELFT>::relocate does and we need to be
consistent. The other option would be to be more explicit about which
relocations are signed and which are not, and sign extend only when
appropriated. That would require extending the target interface.
llvm-svn: 280366
Previously we used LayoutInputSection class to correctly assign
symbols defined in linker script. This patch removes it and uses
pointer to preceding input section in SymbolAssignment class instead.
Differential revision: https://reviews.llvm.org/D23661
llvm-svn: 280348
Target->RelativeRel is used for all platforms, but AMDGPU did
not send that member.
Fixes bug 30227 - RelativeRel is used, but not initialized for AMDGPU.
Differential Revision: https://reviews.llvm.org/D24100
llvm-svn: 280291
Summary:
VERSION commands define symbol versions. The grammar of the
commnad is as follows
VERSION { version-script-commands }
where version-script-commands is
[ name ] { version-definitions }.
Note that we already support version-script-commands because
it is being used for version script command.
This patch is based on George's patch https://reviews.llvm.org/D23609
Reviewers: grimar
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24089
llvm-svn: 280284
Symbol assignments outside of SECTIONS command need to be created
even when SECTIONS command is not used.
Differential Revision: https://reviews.llvm.org/D23751
llvm-svn: 280252
Before this lld was always creating common symbols itself. It worked,
but prevented them from being internalized when possible.
Now it preserves common symbols is the bitcode and they are internalized.
Fixes pr30184.
llvm-svn: 280242
Patch removes VersionScriptParser class and moves the members to ScriptParser
It opens road for implementation of VERSION linkerscript command.
Differential revision: https://reviews.llvm.org/D23774
llvm-svn: 280212
As stated in PR28843:
we should handle command lines with
-target1-rel -target1-abs
--demangle --no-demangle
Patch implements this for specified options.
There are probably other conflicting options can exist,
so fix is called "partial".
Differential revision: https://reviews.llvm.org/D23867
llvm-svn: 280211
This patch groups relative relocations in a single block
in combrelocs mode and adds DT_RELCOUNT or DT_RELACOUNT
tag to .dynamic section
Differential revision: https://reviews.llvm.org/D23661
llvm-svn: 280210
Rui Ueyama