Fix up the new dead code pass to include support for populating the
ctxt "Reachparent" map, which is needed to support field tracking.
Since we don't have sym.Symbols created at the point where new dead
code runs, keep track of reachability using global symbol indices, and
then once loader.LoadFull is complete we can translate the index
mappings into symbol mappings.
The fieldtracking output is unfortunately different relative to
master, due to differences in the order in which symbols are
encountered in deadcode, but I have eyeballed the results to make sure
they look reasonable.
Change-Id: I48c7a4597f05c00f15af3bfd37fc15ab4d0017c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/204342
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
ABI alias references in Go symbols are resolved during
loadObjFull. But for external symbols they are not resolved. If
there is a reference from an external symbol to a Go ABIInternal
symbol, this reference will be invalid as it is not resolved.
The old code resolve ABI aliases in the deadcode pass. But the
new deadcode pass doesn't do it, as it works with indices instead
of Symbols. We do this in LoadFull.
This makes all internal cgo linking tests pass on Mach-O.
Change-Id: Iac6c084c03f5ddbcc9455527800ce7ed7313f9a7
Reviewed-on: https://go-review.googlesource.com/c/go/+/204698
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
In internal linking mode, we need to process cgo_import_static
directives before loading host objects, because the directive is
to tell the host object loader how to deal with imported symbols.
This should fix linking with old object files. I think there
needs some similar logic for new object files, but I'll leave
that for later.
Change-Id: Icaa286de626ea1876086dbdd015047084c92caf9
Reviewed-on: https://go-review.googlesource.com/c/go/+/204697
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Small updates to macho loader, fixing some misunderstandings I had about
using the new object file format.
Change-Id: I9224b01ca327e3a087ebfa36800bd6eef6abcc80
Reviewed-on: https://go-review.googlesource.com/c/go/+/204097
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Add support for elf host objects with new object file format.
Change-Id: Ic5be1953359b9b6b78d9a0b715af69763aefd227
Reviewed-on: https://go-review.googlesource.com/c/go/+/201728
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
dynexp is used for generating the dynamic symbol table. It is
created from a map. Sort it to ensure deterministic order.
Should fix solaris build.
Change-Id: I561b9da3a4136a7ea41139073f76c98fb069d4fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/204378
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
The flags -headerpad, -Wl,-no_pie and -pagezero_size are incompatible with
the -fembed-bitcode flag used by `gomobile build`. Than McIntosh
suggested we might not need the offending flags; this change removes
the flags on darwin/arm64 and -headerpad, -pagezero_size on darwin/arm.
The -Wl,-no_pie flag is left for darwin/arm because linking fails
without it:
ld: warning: PIE disabled. Absolute addressing (perhaps -mdynamic-no-pic) not allowed in code signed PIE, but used in _runtime.rodata from /var/folders/qq/qxn86k813bn9fjxydm095rxw0000gp/T/workdir-host-darwin-amd64-zenly-ios/tmp/go-link-225285265/go.o. To fix this warning, don't compile with -mdynamic-no-pic or link with -Wl,-no_pie
Discussion: https://groups.google.com/d/msg/golang-dev/U1jK3xmmGAk/j0_ty46EDAAJ
I've verified the CL on the builders, built the "flappy" example from
gomobile with `gomobile build`, and verified that flappy runs on an
iPhone 5S.
Updates #32963
Change-Id: I783abc93ccf3c1d2b7ca00144b7164ba223d3529
Reviewed-on: https://go-review.googlesource.com/c/go/+/201358
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Allows Go asm calls referencing a function in a .syso file to be
passed through to the external linker, that would have otherwise
raised a "relocation target X not defined" error in cmd/link.
Fixes#33139
Change-Id: I2a8eb6063ebcd05fac96f141acf7652cf9189766
Reviewed-on: https://go-review.googlesource.com/c/go/+/198798
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
There's no reason not to enable DEP in 2019, especially given Go's
minimum operating system level.
RELNOTE=yes
Change-Id: I9c3bbc5b05a1654876a218123dd57b9c9077b780
Reviewed-on: https://go-review.googlesource.com/c/go/+/203601
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Also a similar 'elapsed' function and its usages were deleted.
Fixes#19865.
Change-Id: Ib125365e69cf2eda60de64fa74290c8c7d1fd65a
Reviewed-on: https://go-review.googlesource.com/c/go/+/171730
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
When using recent versions of gcc with cgo, internal link fails with
c:\>go test debug/pe
--- FAIL: TestInternalLinkerDWARF (0.94s)
file_test.go:394: building test executable for linktype 2 failed: exit status 2 # command-line-arguments
runtime/cgo(.text): relocation target __acrt_iob_func not defined for ABI0 (but is defined for ABI0)
runtime/cgo(.text): relocation target __acrt_iob_func not defined for ABI0 (but is defined for ABI0)
runtime/cgo(.text): relocation target __acrt_iob_func not defined for ABI0 (but is defined for ABI0)
FAIL
FAIL debug/pe 4.572s
FAIL
It appears that __acrt_iob_func is defined in libmsvcrt.a. And this
change adds libmsvcrt.a to the list of libraries always used byi
internal linker.
libmsvcrt.a also implements __imp___acrt_iob_func. So this change
also prevents rewriting __imp___acrt_iob_func name into
__acrt_iob_func, otherwise we end up with duplicate __acrt_iob_func
symbol error.
Fixes#23649
Change-Id: Ie9864cd17e907501e9a8a3672bbc33e02ca20e5c
Reviewed-on: https://go-review.googlesource.com/c/go/+/197977
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
With the previous CL, the export data will not change whether it
is compiled with -dynlink flag or not. Restore the export data
hash, and reenable plugin version check.
TODO: it may be still better to just generate a fingerprint for
each package at compile time.
Change-Id: I1f298ac97c3ab9b8d05d1c95e8be74d10ca7cd0e
Reviewed-on: https://go-review.googlesource.com/c/go/+/201720
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This CL adds basic shared library support in newobj mode. This is
not complete -- there are still tests in misc/cgo/testshared
failing. But at least a simple program works, and some tests
there pass.
Add the mechanism of loading external symbols with contents.
(Before, external symbols are always contentless.) This may
potentially be also used for other host objects.
Change-Id: I68dbf71e7949cc01ebf37ea159084e798ae16925
Reviewed-on: https://go-review.googlesource.com/c/go/+/201537
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Switch the default to new object files.
Internal linking cgo is disabled for now, as it does not work yet
in newobj mode.
Shared libraries are also broken.
Disable some tests that are known broken for now.
Change-Id: I8ca74793423861d607a2aa7b0d89a4f4d4ca7671
Reviewed-on: https://go-review.googlesource.com/c/go/+/200161
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Third change of several to update the loader API to reflect the final
consensus version of the loader API as described in Cherry's doc.
This piece:
- move objfile.Loader into its own separate package, and update
clients accordingly.
This includes a few minor cleanups, including converting a couple
of loader-related functions to methods, and privatizing some of the
loader methods such as ToGlobal/ToLocal.
Change-Id: Iae20585751a45491d8b19dcffc096aadae6bbfc6
Reviewed-on: https://go-review.googlesource.com/c/go/+/200998
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
With the new object files, now we can run the deadcode pass on
indices instead of Symbol structs, so we can delay creating
Symbols after the deadcode pass. Then we only need to create
reachable symbols.
Not create Symbols in LoadNew and LoadRefs, and recombine
LoadReloc into LoadFull.
Split loadcgo into two parts: the first finds root symbols, the
second create Symbols and sets attributes. The first runs before
the deadcode pass, while the second runs after.
TODO: currently there are still symbols that are not marked
reachable but still used. This includes DWARF symbols, file
symbols, and type symbols that are referenced by DWARF symbols.
We still need to create them (conservatively).
Change-Id: I695779c9312be9d49ab1683957ac3e72e1f65a1e
Reviewed-on: https://go-review.googlesource.com/c/go/+/199643
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Switch the deadcode pass to use indices instead of Symbol
structures when using new object file format. Delay loading
symbol relocations and contents fully after the deadcode pass.
The next step is not to create Symbol structures until deadcode
is done.
Method tracking logic hasn't been implemented. Currently, all
methods of a reachable type are live.
Change-Id: Iffcd06ff84e6e52bd9eb24d1220d94234d18ab6b
Reviewed-on: https://go-review.googlesource.com/c/go/+/198199
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
The dev.link branch was not sync'd with the new DWARF compilation
unit logic change on the master branch, and the new object file
format didn't support this.
This CL adds the new DWARF CU and file table support to the new
object file format. In the old object file, the DWARF file table
is a separate section. For now, we do the same with the new
object file, keeping it as a separate block.
While here, also refactor the loader code so it is easier for the
loader to carry per-object informations.
Change-Id: I4c317941fc0a5831acbc11ce8c2a8b7421471372
Reviewed-on: https://go-review.googlesource.com/c/go/+/198198
Reviewed-by: Austin Clements <austin@google.com>
With the old object file format, we use mmap (if supported) to
read object files and back symbol data with mapped read-only
memory.
Do the same with the new object file format. This also
significantly reduces number of syscalls made to read object
files.
Currently we still do mmap in object file level, not archive
level. This is probably ok, as there shouldn't be many archives
that contain more than one object. If this is a problem we can
change that later.
Change-Id: Icae3ef14d8ed6adbee1b5b48d420e2af22fd9604
Reviewed-on: https://go-review.googlesource.com/c/go/+/197797
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
If the new object file format is used, now we load full symbol
contents after the deadcode pass, for reachable symbols only.
We still load some informations early, like relocations and the
contents of type symbols, which are used in the deadcode pass.
If we rewrite deadcode to use index directly, we could delay more
of the loading (to sym.Symbol), and perhaps delay the creation of
sym.Symbol.
TODO: internal linking with host objects doesn't work yet.
Change-Id: I7d4880e8f150e8709ffac277e62191623440e4cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/197258
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Currently we add all text symbols to ctxt.Textp at load time,
then the deadcode pass filters out unreachable ones. This CL
delays adding symbols to ctxt.Textp to the end of the deadcode
pass, where we only add reachable ones.
Change-Id: Ie83b2958f915c5aaa004b8c5ed1f1bc275f4d1db
Reviewed-on: https://go-review.googlesource.com/c/go/+/197257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This is in preparation of delaying loading symbol content to
after dead code elimination.
Change-Id: Ia4ce82d9a42cc1a76c82f6d0eb9a54b0325ee3ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/197061
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Parse new object file format in the linker. At least we can link
a hello-world program.
Add a basic "loader", which handles symbol references in the
object file.
- mapping between local and global indices
- resolve by-name references
(TODO: the overwrite logic isn't implemented yet)
Currently we still create sym.Symbol rather early, and, after all
the object files are loaded and indexed references are resolved,
add all symbols to sym.Symbols.
The code here is probably not going in the final version. This
is basically only for debugging purposes -- to make sure the
writer and the reader work as expected.
Change-Id: I895aeea68326fabdb7e5aa1371b8cac7211a09dd
Reviewed-on: https://go-review.googlesource.com/c/go/+/196032
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Fix linking with a package having a .syso file in external link mode,
that would otherwise cause an error before executing the external
linker because it can't find symbols that are exported in the said
.syso file.
Fixes#33139
Change-Id: Id3ee737fba1c6f1e37910593dfedf9c84486d398
Reviewed-on: https://go-review.googlesource.com/c/go/+/186417
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Remove linker reading and processing of automs (no longer needed, now
that the compiler is emitting R_USETYPE relocations on functions). So
as to avoid changing the object file format, the object still contains
a count of automs, but this count is required to be zero.
Updates #34554.
Change-Id: I10230e191057c5c5705541eeb06f747d5f73c42d
Reviewed-on: https://go-review.googlesource.com/c/go/+/197500
Reviewed-by: Jeremy Faller <jeremy@golang.org>
As we move the debug_line generation into the compiler, we need to
upgrade the notion of compilationUnit to not just be on a per package
basis. That won't be the case as it will be impossible for all
compilationUnits to have the same set of files names used to build the
debug_lines table. (For example, assembled files in a package don't know
about any files but themselves, so the debug_lines table could only
reference themseves. As such, we need to break the 1:1 relationship
between compUnit and package.)
Change-Id: I2e517bb6c01de0115bbf777af828a2fe59c09ce8
Reviewed-on: https://go-review.googlesource.com/c/go/+/189618
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
I'm branching this off cl/187117, and will be reworking that diff stack.
Testing: I've run go build -toolexec 'toolstash -cmp'
Change-Id: I922a97d0f25d52ea70cd974008a063d4e7af34a7
Reviewed-on: https://go-review.googlesource.com/c/go/+/188023
Reviewed-by: Austin Clements <austin@google.com>
Perform a single lookup of "plugin.Open" at the point where we set the
loaded flag for the context, then cache whether the result is nil, so
that we can consult this cached value later on (instead of having to
look up the symbol each time). This helps speed up the DynLinkingGo()
context method, which is called from within some very hot loops in the
linker (when linking 'hyperkube' from kubernetes, reduces total calls
to "sym.(*Symbols).ROLookup" from 6.5M to 4.3M)
Change-Id: I92a2ea2b21d24f67aec0a7afeef4acc77c095adf
Reviewed-on: https://go-review.googlesource.com/c/go/+/193260
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Previously users who opted into cgo might have received a bit of a
behavior surprise when their mingw installation defaulted to a
potentially older and different set of compatibility hacks. Since Go is
explicitly targeting >=6.1 for internal linkage, propagate these changes
to external linkage too.
While we're at it, we move these values into constant variables so that
they don't become out of sync and allow for easy updating as Go
gradually drops compatibility for older operating systems.
Change-Id: I41e654d135be6e3db9088e73efeb414933e36caa
Reviewed-on: https://go-review.googlesource.com/c/go/+/191842
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
This has been the default in MSVC for a very long time, and it's hard to
imagine modern programs actually wanting the old legacy behavior. For
example, no modern programs try to install their junk into C:\windows
and therefore need to have an emulated writable windows directory.
That's not really even allowed by ACLs on modern systems.
Change-Id: Iadaca6815e39ea5c6b05c1cac5a95cfc35e5b48a
Reviewed-on: https://go-review.googlesource.com/c/go/+/191840
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
There is real (albeit generated) code that exceeds the limit.
Fixes#33555
Change-Id: I668e85825d3d2a471970e869abe63f3492213cc1
Reviewed-on: https://go-review.googlesource.com/c/go/+/189697
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
These functions are compiler generated, and as such are only available
in the internal ABI. Doing this avoids generating an alias symbol.
Doing that avoids confusion between unmangled and mangled type symbols.
Fixes#30768
Change-Id: I197a5ba6403aac11989ffa951dbe35bd0506de91
Reviewed-on: https://go-review.googlesource.com/c/go/+/186077
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Renaming the method makes clear, both to readers and to vet,
that this method is not the implementation of io.Seeker:
it cannot fail.
Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.
For #31916.
Change-Id: I3e6ad7264cb0121b4b76935450cccb71d533e96b
Reviewed-on: https://go-review.googlesource.com/c/go/+/176108
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This CL improves internal link to provide basic support for cgo and PIE:
1, add support for GOT, PLT and GOTPLT.
2, add support for following ELF relocation types which have been used by std
packages:
R_AARCH64_ADR_GOT_PAGE
R_AARCH64_LD64_GOT_LO12_NC
R_AARCH64_ADR_PREL_PG_HI21
R_AARCH64_ADD_ABS_LO12_NC
R_AARCH64_LDST8_ABS_LO12_NC
R_AARCH64_LDST32_ABS_LO12_NC
R_AARCH64_LDST64_ABS_LO12_NC
R_AARCH64_JUMP26
R_AARCH64_ABS64
R_AARCH64_PREL32
R_AARCH64_PREL64
With this change, Go toolchain can be built in internal linking mode, and
pure Go programs can be built with PIE mode in internal linking mode on arm64.
Updates #10373
The prototype of this CL is contributed by Wei Xiao <wei.xiao@arm.com>
Change-Id: I2253923c69e855fd1524d54def309a961dce6247
Reviewed-on: https://go-review.googlesource.com/c/go/+/163579
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
.go.buildinfo must be added to the symbol table on AIX. Otherwise, ld
won't be able to handle its relocations.
This patch also make ".data" the default section for all symbols inside
the data segment.
Change-Id: I83ac2bf1050e0ef6ef9c96ff793efd4ddc8e98d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/174298
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Determine the macho platform once and use that the two places that
need it. This makes it easier to add a third platform check for a
follow-up change.
Updates #31447
Change-Id: I522a5fface647ab8e608f816c5832d531534df7a
Reviewed-on: https://go-review.googlesource.com/c/go/+/174198
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Use mmap for writing most of the output file content,
specifically, the sections and segments. After layout, we
already know the sizes and file offsets for the sections and
segments. So we can just write the bytes by copying to a mmap'd
backing store.
The writing of the output file is split into two parts. The first
part writes the sections and segments to the mmap'd region. The
second part writes some extra content, for which we don't know
the size, so we use direct file IO.
This is in preparation for mmap'ing input files read-only.
Change-Id: I9f3b4616a9f96bfd5c940d74c50aacd6d330f7d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/170738
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Rename it to PCIter and convert it to use methods.
Set pcscale once, during construction, to make call sites clearer.
Change some ints to bools.
Use a simple iteration termination condition,
instead of the cap comparison from the c2go translation.
Instead of requiring a Pcdata, which requires one caller
to synthesize a fake Pcdata, just ask for a byte slice.
Passes toolstash-check.
Change-Id: I811da0e929cf4a806bd6d70357ccf2911cd0c737
Reviewed-on: https://go-review.googlesource.com/c/go/+/171770
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Update the recently-added '-strictdups' sanity checking to avoid
failing the link in cases where we have objects feeding into the link
with a mix of command line flags (and in particular some with "-N" and
some without). This scenario will trigger errors/warnings due to
inlinable functions and wrapper functions that have different sizes
due to presence or lack of optimization.
Update #31034.
Change-Id: I1dd9e37c2f9bea5da0ab82e32e6fc210aebf6a65
Reviewed-on: https://go-review.googlesource.com/c/go/+/169160
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Change-Id: Ia268b0d64dc89866aa09bfffcaa109741088a904
Reviewed-on: https://go-review.googlesource.com/c/go/+/169119
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We don't use the TLS section on android, and dropping it avoids
complaints about underalignment from the Android Q linker.
Updates #29674
Change-Id: I91dabf2a58e6eb1783872639a6a144858db09cef
Reviewed-on: https://go-review.googlesource.com/c/go/+/169618
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Introduce a new linker command line option "-strictdups", which
enables sanity checking of "ok to duplicate" symbols, especially
DWARF info symbols. Acceptable values are 0 (no checking) 1 (issue
warnings) and 2 (issue a fatal error checks fail).
Currently if we read a DWARF symbol (such as "go.info.PKG.FUNCTION")
from one object file, and then encounter the same symbol later on
while reading another object file, we simply discard the second one
and move on with the link, since the two should in theory be
identical.
If as a result of a compiler bug we wind up with symbols that are not
identical, this tends to (silently) result in incorrect DWARF
generation, which may or may not be discovered depending on who is
consuming the DWARF and what's being done with it.
When this option is turned on, at the point where a duplicate
symbol is detected in the object file reader, we check to make sure
that the length/contents of the symbol are the same as the previously
read symbol, and print a descriptive warning (or error) if not.
For the time being this can be used for one-off testing to find
problems; at some point it would be nice if we can enable it by
default.
Updates #30908.
Change-Id: I64c4e07c326b4572db674ff17c93307e2eec607c
Reviewed-on: https://go-review.googlesource.com/c/go/+/168410
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Change-Id: I939518462c931ba9feb125b2f299ef0706b124ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/168879
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We're going to need the ability to extract the LC_VERSION_MIN_* and
LC_BUILD_VERSION load commands. This CL adds peekMachoPlatform to do
that and in the process simplifies machoCombineDwarf.
While here, disable DWARF combining for Apple platforms other than
macOS (watchOS, tvOS, bridgeOS), not just iOS.
Updates #22395
Change-Id: I4862b0f15ccc87b7be1a6532b4d37b47c8f7f243
Reviewed-on: https://go-review.googlesource.com/c/go/+/168459
Reviewed-by: Ian Lance Taylor <iant@golang.org>
