Users are exepcted to pass all .res files to the linker, which then
merges all the resource in all .res files into a tree structure and then
converts the final tree structure to a .obj file with .rsrc$01 and
.rsrc$02 sections and then links that.
If the user instead passes several .obj files containing such resources,
the correct thing to do would be to have custom code to merge the trees
in the resource sections instead of doing normal section merging -- but
link.exe rejects if multiple resource obj files are passed in with
LNK4078, so let lld-link do that too instead of silently writing broken
.rsrc sections in that case.
The only real way to run into this is if users manually convert .res
files to .obj files by running cvtres and then handing the resulting
.obj files to lld-link instead, which in practice likely never happens.
(lld-link is slightly stricter than link.exe now: If link.exe is passed
one .obj file created by cvtres, and a .res file, for some reason it
just emits a warning instead of an error and outputs strange looking
data. lld-link now errors out on mixed input like this.)
One way users could accidentally run into this is the following
scenario: If a .res file is passed to lib.exe, then lib.exe calls
cvtres.exe on the .res file before putting it in the output .lib.
(llvm-lib currently doesn't do this.)
link.exe's /wholearchive seems to only add obj files referenced from the
static library index, but lld-link current really adds all files in the
archive. So if lld-link /wholearchive is used with .lib files produced
by lib.exe and .res files were among the files handed to lib.exe, we
previously silently produced invalid output, but now we error out.
link.exe's /wholearchive semantics on the other hand mean that it
wouldn't load the resource object files from the .lib file at all.
Since this scenario is probably still an unlikely corner case,
the difference in behavior here seems fine -- and lld-link might have to
change to use link.exe's /wholearchive semantics in the future anyways.
Vaguely related to PR42180.
Differential Revision: https://reviews.llvm.org/D63109
llvm-svn: 363078
For lld, pass in Config->Timestamp (which is set based on lld's
/timestamp: and /Brepro flags). Since the writeWindowsResourceCOFF()
data is only used in-memory by LLD and the obj's timestamp isn't used
for anything in the output, this doesn't change behavior.
For llvm-cvtres, add an optional /timestamp: parameter, and use the
current behavior of calling time() if the parameter is not passed in.
This doesn't really change observable behavior (unless someone passes
/timestamp: to llvm-cvtres, which wasn't possible before), but it
removes the last unqualified call to time() from llvm/lib, which seems
like a good thing.
Differential Revision: https://reviews.llvm.org/D63116
llvm-svn: 363050
And share some code with lld-link.
While here, also add a FIXME about PR42180 and merge r360150 to llvm-lib.
Differential Revision: https://reviews.llvm.org/D63021
llvm-svn: 363016
Summary:
When handling exports from the command line or from .def files, the
linker does a "fuzzy" string lookup to allow finding mangled symbols.
However, when the symbol is re-exported under a new name, the linker has
to transfer the decorations from the exported symbol over to the new
name. This is implemented by taking the mangled symbol that was found in
the object and replacing the original symbol name with the export name.
Before this patch, LLD implemented the fuzzy search by adding an
undefined symbol with the unmangled name, and then during symbol
resolution, checking if similar mangled symbols had been added after the
last round of symbol resolution. If so, LLD makes the original symbol a
weak alias of the mangled symbol. Later, to get the original symbol
name, LLD would look through the weak alias and forward it on to the
import library writer, which copies the symbol decorations. This
approach doesn't work when bar is itself a weak alias, as is the case in
asan. It's especially bad when the aliasee of bar contains the string
"bar", consider "bar_default". In this case, we would end up exporting
the symbol "foo_default" when we should've exported just "foo".
To fix this, don't look through weak aliases to find the mangled name.
Save the mangled name earlier during fuzzy symbol lookup.
Fixes PR42074
Reviewers: mstorsjo, ruiu
Subscribers: thakis, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62984
llvm-svn: 362849
OptTable treats arguments starting with / that aren't a known option
as filenames. This means lld-link's and clang-cl's typo correction for
unknown flags didn't do spell checking for misspelled options that start
with /.
I first tried changing OptTable, but that got pretty messy, see PR41787
comments 2 and 3.
Instead, let lld-link's and clang's (including clang-cl's) "file not
found" diagnostic check if a non-existent file looks like it could be a
mis-spelled option, and if so add a "did you mean" suggestion to the
"file not found" diagnostic.
While here, make formatting of a few diagnostics a bit more
self-consistent.
Fixes PR41787.
Differential Revision: https://reviews.llvm.org/D62276
llvm-svn: 361518
For lld-link, unknown '/'-style flags are treated as filenames on POSIX
systems, so only '-'-style flags get typo correction for now. This
matches clang-cl.
PR37006.
Differential Revision: https://reviews.llvm.org/D61443
llvm-svn: 360145
As a side benefit, lld-link now reports more than one duplicate resource
entry before exiting with an error even if the new flag is not passed.
llvm-svn: 359829
Reduces the error message from:
lld-link: error: failed to parse .res file: duplicate resource: type STRINGTABLE (ID 6)/name ID 3/language 1033, in test1.res and in test2.res
To:
lld-link: error: duplicate resource: type STRINGTABLE (ID 6)/name ID 3/language 1033, in test1.res and in test2.res
Make sure every error message emitted by cvtres contains the name of at
least one ".res" file, so that removing the "failed to parse .res file"
string doesn't lose information.
Differential Revision: https://reviews.llvm.org/D61388
llvm-svn: 359749
r191276 added this to old LLD, but it never made it to new LLD -- except
that the flag was in Options.td, so it was silently ignored. I figured
it should be easy to implement, so I did that instead of removing the
flags from Options.td.
I then discovered that link.exe also supports comma-separated lists of
'cd' and 'net', which made the parsing code a bit annoying.
The Alias technique in Options.td is to get nice help output.
Differential Revision: https://reviews.llvm.org/D61067
llvm-svn: 359192
When mismatched #pragma detect_mismatch declarations occur, now print the conflicting OBJs.
lld-link: error: /failifmismatch: mismatch detected for 'TEST':
>>> test.obj has value 1
>>> test2.obj has value 2
Fixes PR38579
Differential Revision: https://reviews.llvm.org/D58910
llvm-svn: 355543
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: Before, OptTable::PrintHelp append "[options] <inputs>" to its parameter `Help`. It is more flexible to change its semantic to `Usage` and let user customize the usage line.
Reviewers: rupprecht, ruiu, espindola
Reviewed By: rupprecht
Subscribers: emaste, sbc100, arichardson, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D53054
llvm-svn: 344099
This was useful for LTO bringup in lld-link while lld couldn't write PDBs. Now
that it can, this should no longer be needed. Hopefully the flag is obscure
enough and recent enough, that nobody uses it – but if somebody should use it,
they should be able to just stop passing it and things should continue to work.
https://reviews.llvm.org/D50139
llvm-svn: 338615
This simplifies some code which had StringRefs to begin with, and
makes other code more complicated which had const char* to begin
with.
In the end, I think this makes for a more idiomatic and platform
agnostic API. Not all platforms launch process with null terminated
c-string arrays for the environment pointer and argv, but the api
was designed that way because it allowed easy pass-through for
posix-based platforms. There's a little additional overhead now
since on posix based platforms we'll be takign StringRefs which
were constructed from null terminated strings and then copying
them to null terminate them again, but from a readability and
usability standpoint of the API user, I think this API signature
is strictly better.
llvm-svn: 334518
This is most useful when using lld-link on a non-Win host (but it might become
useful on Windows too if lld also grows a fansi-escape-codes flag).
Also make the help for --color-diagnostic mention the valid values in ELF and
wasm, and print the flag name with two dashes in diags, since the one-dash form
is seen as a list of many one-letter flags in some contexts.
https://reviews.llvm.org/D46693
llvm-svn: 332012
GNU ld has got a number of different flags for adjusting how to
behave around stdcall functions. The --kill-at flag strips the
trailing sdcall suffix from exported functions (which otherwise
is included by default in MinGW setups).
This also strips it from the corresponding import library though.
That makes it hard to link to such an import library from code
that calls the functions - but this matches what GNU ld does with
this flag. Therefore, this flag is probably not sensibly used
together with import libraries, but probably mostly when creating
some sort of plugin, or if creating the import library separately
with dlltool.
Differential Revision: https://reviews.llvm.org/D44292
llvm-svn: 327561
This makes the output of some flag names in warning messages consistent with
the output of /? and the output of flags in most other diagnostics.
https://reviews.llvm.org/D44307
llvm-svn: 327261
Summary:
This protects calls to longjmp from transferring control to arbitrary
program points. Instead, longjmp calls are limited to the set of
registered setjmp return addresses.
This also implements /guard:nolongjmp to allow users to link in object
files that call setjmp that weren't compiled with /guard:cf. In this
case, the linker will approximate the set of address taken functions,
but it will leave longjmp unprotected.
I used the following program to test, compiling it with different -guard
flags:
$ cl -c t.c -guard:cf
$ lld-link t.obj -guard:cf
#include <setjmp.h>
#include <stdio.h>
jmp_buf buf;
void g() {
printf("before longjmp\n");
fflush(stdout);
longjmp(buf, 1);
}
void f() {
if (setjmp(buf)) {
printf("setjmp returned non-zero\n");
return;
}
g();
}
int main() {
f();
printf("hello world\n");
}
In particular, the program aborts when the code is compiled *without*
-guard:cf and linked with -guard:cf. That indicates that longjmps are
protected.
Reviewers: ruiu, inglorion, amccarth
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43217
llvm-svn: 325047
Summary:
This patch adds some initial support for Windows control flow guard. At
the end of the day, the linker needs to synthesize a table of RVAs very
similar to the structured exception handler table (/safeseh).
Both /safeseh and /guard:cf take sections of symbol table indices
(.sxdata and .gfids$y) and turn them into RVA tables referenced by the
load config struct in the CRT through special symbols.
Reviewers: ruiu, amccarth
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42592
llvm-svn: 324306
The compiler could not find the conversion from
unique_ptr<WritableMemoryBuffer> to unique_ptr<MemoryBuffer>. This will
hopefully help it along.
llvm-svn: 322365
Patch by Takuto Ikuta.
This patch reduces lld link time of chromium's blink_core.dll in
component build.
Total size of input argument in .directives become nearly 300MB in the
build and almost all its content are /EXPORT.
To reduce time of parsing too many /EXPORT option in the build, I
introduce fastpath for /EXPORT in ArgParser::parseDirectives.
On my desktop machine, 4 times stats of the link time are like below.
Improved around 20%.
This patch
TotalSeconds : 8.6217627
TotalSeconds : 8.5402175
TotalSeconds : 8.6855853
TotalSeconds : 8.3624441
Ave : 8.5525024
master
TotalSeconds : 10.9975031
TotalSeconds : 11.3409428
TotalSeconds : 10.6332897
TotalSeconds : 10.7650687
Ave : 10.934201075
llvm-svn: 322117
Patch by Takuto Ikuta.
This patch reduces link time of chromium's blink_core.dll in component
build. Total size of input argument in .directives become nearly 300MB
in the build and no rsp file is used. Speedup link by skipping duplicate
parsing.
On my desktop machine, 4 times stats are like below. Improved around 15%.
This patch
TotalSeconds : 18.408538
TotalSeconds : 17.2996744
TotalSeconds : 17.1053862
TotalSeconds : 17.809777
avg: 17.6558439
master
TotalSeconds : 20.9290504
TotalSeconds : 19.9158213
TotalSeconds : 21.0643515
TotalSeconds : 20.8775831
avg: 20.696701575
Differential Revision: https://reviews.llvm.org/D41581
llvm-svn: 321470
This patch is to rename check CHECK and make it a C macro, so that
we can evaluate the second argument lazily.
Differential Revision: https://reviews.llvm.org/D40915
llvm-svn: 319974
Now that we have only SymbolBody as the symbol class. So, "SymbolBody"
is a bit strange name now. This is a mechanical change generated by
perl -i -pe s/SymbolBody/Symbol/g $(git grep -l SymbolBody lld/ELF lld/COFF)
nd clang-format-diff.
Differential Revision: https://reviews.llvm.org/D39459
llvm-svn: 317370
Summary:
The COFF linker and the ELF linker have long had similar but separate
Error.h and Error.cpp files to implement error handling. This change
introduces new error handling code in Common/ErrorHandler.h, changes the
COFF and ELF linkers to use it, and removes the old, separate
implementations.
Reviewers: ruiu
Reviewed By: ruiu
Subscribers: smeenai, jyknight, emaste, sdardis, nemanjai, nhaehnle, mgorny, javed.absar, kbarton, fedor.sergeev, llvm-commits
Differential Revision: https://reviews.llvm.org/D39259
llvm-svn: 316624
link.exe supports this option to convert warnings into errors, and it's
useful to support in LLD as well.
Differential Revision: https://reviews.llvm.org/D39148
llvm-svn: 316502
Now that we have our own implementation of cvtres, we can add resource
files directly to the linkrepro.
Differential Revision: https://reviews.llvm.org/D38974
llvm-svn: 315954
Without this, /linkrepro would create an invalid tar file.
No tests because this requires Windows and the linkrepro tests
require not-Windows.
Differential Revision: https://reviews.llvm.org/D38973
llvm-svn: 315948
Summary:
Previous would throw warning whenever libxml2 is not installed. Now
only give this warning if merging manifest fails.
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37240
llvm-svn: 312604
Looks like raw_string_ostream is buffered. If we do not call `flush`
nor `str`, it is not guaranteed that a result string has all characters
that were written to it.
It wasn't failing on buildbots, but I could reproduce the issue on my
Windows workstation.
llvm-svn: 312577
Summary:
ArgParser created an instance of COFFOptTable on stack to use it to
parser command line arguments. Parsed arguments were then returned from
the function as InputArgList. This was safe because InputArgList referred
only statically-allocated InfoTable.
That is not a safe assumption after https://reviews.llvm.org/D36782,
which changes the type of its internal table from ArrayRef to std::vector.
To make lld work with that patch, we need to keep an instance of
COFFOptTable at least as long as an InputArgList is alive. This patch
does that.
Reviewers: yamaguchi
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37217
llvm-svn: 311930
Summary: Now that the llvm-mt manifest merging libraries are complete, we may use them to merge manifests instead of needing to shell out to mt.exe.
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D36255
llvm-svn: 311424
These are emitted for comm symbols in object files, when targeting
a GNU environment.
Alternatively, just ignore them since we already align CommonChunk
to the natural size of the content (up to 32 bytes). That would only
trade away the possibility to overalign small symbols, which doesn't
sound like something that might not need to be handled?
Differential Revision: https://reviews.llvm.org/D36304
llvm-svn: 310871
Nico Weber