This is much easier than replacing SSUB so split it out from my other CL.
Change-Id: If01e4005da5355895404456320a2156bde4ec09a
Reviewed-on: https://go-review.googlesource.com/71050
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This is https://go-review.googlesource.com/42025 but with some more fixes --
hidden symbols implicitly passed "Type == 0 || Type == SXREF" checks. (This
sort of thing is part of why I wanted to make this change)
Change-Id: I2273ee98570fd7f2dd8a799c692a2083c014235e
Reviewed-on: https://go-review.googlesource.com/42330
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
CL 69370 introduced a hasmain field to moduledata after the
modulehashes slice. However that code was relying on the zeroing
code after it to cover modulehashes if len(Shlibs) == 0. The
hasmain field gets in the way of that. So clear modulehashes
explicitly in that case.
Found when looking at #22250. Not sure if it's related.
Change-Id: I81050cb4554cd49e9f245d261ef422f97d026df4
Reviewed-on: https://go-review.googlesource.com/70730
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently we look to see if the main.main symbol address is in the
module data text range. This requires access to the main.main
symbol, which usually the runtime has, but does not when building
a plugin.
To avoid a dynamic relocation to main.main (which I haven't worked
out how to have the linker generate on darwin), stop using the
symbol. Instead record a boolean in the moduledata if the module
has the main function.
Fixes#22175
Change-Id: If313a118f17ab499d0a760bbc2519771ed654530
Reviewed-on: https://go-review.googlesource.com/69370
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For #22095
Change-Id: I8f48fce571b69a7e8edf2ad7733ffdfd38676e63
Reviewed-on: https://go-review.googlesource.com/70310
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
When we split separate packages into separate compilation units, we
lost PC range information because it was no longer contiguous. This
brings it back by constructing proper per-package PC range tables.
Change-Id: Id0ab5187e08ac5d13b3d3794977bfc857a56224f
Reviewed-on: https://go-review.googlesource.com/69974
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Currently, the linker generates one huge DWARF compilation unit for
the entire Go binary. This commit creates a separate compilation unit
and line table per Go package.
We temporarily lose compilation unit PC range information, since it's
now discontiguous, so harder to emit. We'll bring it back in the next
commit.
Beyond being "more traditional", this has various technical
advantages:
* It should speed up line table lookup, since that requires a
sequential scan of the line table. With this change, a debugger can
first locate the per-package line table and then scan only that line
table.
* Once we emit compilation unit PC ranges again, this should also
speed up various other debugger reverse PC lookups.
* It puts us in a good position to move more DWARF generation into the
compiler, which could produce at least the CU header, per-function
line table fragments, and per-function frame unwinding info that the
linker could simply paste together.
* It will let us record a per-package compiler command-line flags
(#22168).
Change-Id: Ibac642890984636b3ef1d4b37fe97f4453c2cc84
Reviewed-on: https://go-review.googlesource.com/69973
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The DWARF code currently clears all section relocations every time it
creates a section. This is unnecessary and confusing, so don't do it.
This dates back to
https://codereview.appspot.com/7891044/diff/26001/src/cmd/ld/dwarf.c.
At the time, this was only done for one symbol and that symbol was
used solely for collecting relocations (which is why it made sense to
clear the relocations but not the actual data). Furthermore, DWARF
generation potentially required two passes, so it was important to
clear the state from the first pass. None of this is true now, but
this pattern had been cargo-culted all over the dwarf.go.
Change-Id: I87d4ff8ccd5c807796241559be46168ce3ccb49a
Reviewed-on: https://go-review.googlesource.com/70312
Run-TryBot: Austin Clements <austin@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The .debug_aranges section is an odd vestige of DWARF, since its
contents are easy and efficient for a debugger to reconstruct from the
attributes of the top-level compilation unit DIEs. Neither GCC nor
clang emit it by default these days. GDB and Delve ignore it entirely.
LLDB will use it if present, but is happy to construct the index from
the compilation unit attributes (and, indeed, a remarkable variety of
other ways if those aren't available either).
We're about to split up the compilation units by package, which means
they'll have discontiguous PC ranges, which is going to make
.debug_aranges harder to construct (and larger).
Rather than try to maintain this essentially unused code, let's
simplify things and remove it.
Change-Id: I8e0ccc033b583b5b8908cbb2c879b2f2d5f9a50b
Reviewed-on: https://go-review.googlesource.com/69972
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
During Mach-O linking, dsymutil takes the DWARF from individual object
files and combines it into a debug archive. Because it's content-aware,
it doesn't need our help to do its job. Nonetheless, it does try to
honor relocations that are present in its input.
When dsymutil encounters a relocation, it uses the value of that
relocation as an index into the debug map to find its final location.
When it does that, it's assuming that the value is an address in the
object file. But DWARF references are section-relative. So when it
processes a relocation for a DWARF reference, it gets confused,
and if the value happens to match the address of a function or
data symbol, it will rewrite it incorrectly.
Since the relocations don't help, and can hurt, drop them when
externally linking a Mach-O binary.
Fixes#22068
Change-Id: I8ec36da626575d9f6c8d0e7a0b76eab8ba22d62c
Reviewed-on: https://go-review.googlesource.com/68330
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Along the way, switch to using relocation constants from debug/elf.
For #22095
Change-Id: I1a64353619f95dde5aa39060c4b9d001af7dc1e4
Reviewed-on: https://go-review.googlesource.com/69013
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
There are two places in DWARF generation that create symbols when they
really just want to get the symbol if it exists. writeranges, in
particular, will create a DWARF range symbol for every single textp
symbol (though they won't get linked into any list, so they don't
affect the binary).
Fix these to use ROLookup instead of Lookup.
Change-Id: I401eadf22890e296bd08bccaa6ba2fd8fac800cd
Reviewed-on: https://go-review.googlesource.com/69971
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Thanks to Christopher Nelson for spearheading the effort.
Fixes#11058
Change-Id: Icafabac8dc697626ff1bd943cc577b0b1cc6b349
Reviewed-on: https://go-review.googlesource.com/69091
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Move some local declarations closer to their use, reducing their
respective lifetimes, also improve few error messages.
Follow up of CL 67370.
Updates #22095
Change-Id: I6131159ae8de571015ef5459b33d5c186e543a37
Reviewed-on: https://go-review.googlesource.com/69110
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
For #22095
Change-Id: I660080279692b74669c45f42c28cccff71bd33b5
Reviewed-on: https://go-review.googlesource.com/68930
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also add -V=full to print a unique identifier of the specific tool being invoked.
This will be used for content-based staleness.
Also sort and clean up a few of the flag doc comments.
Change-Id: I786fe50be0b8e5f77af809d8d2dab721185c2abd
Reviewed-on: https://go-review.googlesource.com/68590
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Replace Buildmode with BuildMode and Linkmode with LinkMode.
For #22095
Change-Id: I51a6f5719d107727bca29ec8e68e3e9d87e31e33
Reviewed-on: https://go-review.googlesource.com/68334
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
For #22095
Change-Id: Ie9ae84c758af99ac7daed26d0b3e3b0a47599edd
Reviewed-on: https://go-review.googlesource.com/67315
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For #22095
Change-Id: I2cb0d3e0aaf9f97952cf8dda0e99a4379e275020
Reviewed-on: https://go-review.googlesource.com/68332
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For #22095
Change-Id: I07c288208d94dabae164c2ca0a067402a8e5c2e6
Reviewed-on: https://go-review.googlesource.com/68331
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Moves type symbol name mangling out of the object reader
and into a separate pass. Requires some care, as changing
the name of a type may require dealing with duplicate
symbols for the first time.
Disables DWARF for both plugins and programs that use plugin.Open,
because type manging is currently incompatible with the go.info.*
symbol generator in cmd/link. (It relies on the symbol names to
find type information.) A future fix for this would be moving the
go.info.* generation into the compiler, with the logic we use
for generating the type.* symbols.
Fixes#19529
Change-Id: I75615f8bdda86ff9e767e536d9aa36e15c194098
Reviewed-on: https://go-review.googlesource.com/67312
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently the linker figures out where runtime-gdb.py should be by
looking for the path to runtime/debug.go. However, debug.go contains
only a few symbols and can easily get dead-code eliminated entirely,
especially from simple binaries. When this happens, the resulting
binary lacks a reference to runtime-gdb.py, so the GDB helpers don't
get loaded.
Fix this by instead sniffing for runtime/proc.go. This contains
runtime.main and the scheduler, so it's not going anywhere.
Change-Id: Ie3380c77c840d28614fada68b8c5861625f2aff5
Reviewed-on: https://go-review.googlesource.com/68019
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Preparation for moving the object file reader to its own package.
For #22095
Change-Id: I31fe4a10a2c465f8ea4bf548f40918807e4ec6b5
Reviewed-on: https://go-review.googlesource.com/67314
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Also reduce the passed context from *Link to *sys.Arch, so fewer
data dependencies need to be wired through all the code dealing
with symbols.
For #22095
Change-Id: I50969405d6562c5152bd1a3c443b72413e9b70bc
Reviewed-on: https://go-review.googlesource.com/67313
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Begin passing coutbuf by as a parameter. To make the initial plumbing
pass easier, it is also a field in the standard ctxt parameter.
Consolidate the byte writing functions into the OutBuf object.
The result is less architecture-dependent initialization.
To avoid plumbing out everywhere we want to report an error, move
handling of out file deletion to an AtExit function.
For #22095
Change-Id: I0863695241562e0662ae3669666c7922b8c846f9
Reviewed-on: https://go-review.googlesource.com/67318
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For #22095
Change-Id: I9d1f0d93f8fd701a24af826dc903eea2bc235de2
Reviewed-on: https://go-review.googlesource.com/67317
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Move some local declarations closer to their use, reducing their
respective lifetimes. Spotted while reviewing CL 67318.
Change-Id: I68db67fe8530344d95e50efb6587bc724e1171f5
Reviewed-on: https://go-review.googlesource.com/67370
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a step toward using cached build artifacts: the importcfg
will direct the compiler and linker to read them right from the cache
if necessary. However, this CL does not have a cache yet, so it still
reads them from the usual install location or build location.
Even so, this fixes a long-standing issue that -I and -L (no longer used)
are not expressive enough to describe complex GOPATH setups.
Shared libraries are handled enough that all.bash passes, but
there may still be more work to do here. If so, tests and fixes
can be added in follow-up CLs.
Gccgo will need updating to support -importcfg as well.
Fixes#14271.
Change-Id: I5c52a0a5df0ffbf7436e1130c74e9e24fceff80f
Reviewed-on: https://go-review.googlesource.com/56279
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
bytes.IndexByte can be used wherever the second argument to
strings.Index is exactly one byte long, so we do that with this change.
This avoids generating unnecessary string symbols/converison and saves
a few calls to bytes.Index.
Change-Id: If31c775790e01edfece1169e398ad6a754fb4428
Reviewed-on: https://go-review.googlesource.com/66373
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The internal linker doesn't know how to handle multiple TOC sections
in internal linking mode. This used to work because before CL 64793 we
invoked ld -r on multiple objects, and that merged the TOC sections
for us.
Updates #21961
Change-Id: I48260a7195be660016f2f358ebc8cb79652210ab
Reviewed-on: https://go-review.googlesource.com/66270
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
strings.IndexByte was introduced in go1.2 and it can be used
effectively wherever the second argument to strings.Index is
exactly one byte long.
This avoids generating unnecessary string symbols and saves
a few calls to strings.Index.
Change-Id: I1ab5edb7c4ee9058084cfa57cbcc267c2597e793
Reviewed-on: https://go-review.googlesource.com/65930
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: I33284d3154db43b2b89418c5076df79407e7cf41
Reviewed-on: https://go-review.googlesource.com/60931
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
https://golang.org/cl/5822049 introduced the idea of linking together
all the cgo objects with -r, while also linking against -lgcc. This
was to fix http://golang.org/issue/3261: cgo code that requires libgcc
would break when using internal linking.
This approach introduced https://golang.org/issue/9510: multiple
different cgo packages could include the same libgcc object, leading
to a multiple definition error during the final link. That problem was
fixed by https://golang.org/cl/16741, as modified by
https://golang.org/cl/16993, which did the link against libgcc only
during the final link.
After https://golang.org/cl/16741, and, on Windows, the later
https://golang.org/cl/26670, ld -r no longer does anything useful.
So, remove it.
Doing this revealed that running ld -r on Darwin simplifies some
relocs by making them specific to a symbol rather than a section.
Correct the handling of unsigned relocations in internal linking mode
by offsetting by the symbol value. This only really comes up when
using the internal linker with C code that initializes a variable to
the address of a local constant, such as a C string (as in const char
*s = "str";). This change does not affect the normal case of external
linking, where the Add field is ignored. The test case is
misc/cgo/test/issue6612.go in internal linking mode.
The cmd/internal/goobj test can now see an external object with no
symbol table; fix it to not crash in that case.
Change-Id: I15e5b7b5a8f48136bc14bf4e1c4c473d5eb58062
Reviewed-on: https://go-review.googlesource.com/64793
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
In general, there are no guarantee that `go` command exist on $PATH.
This CL tries to get `go` command from $GOROOT/bin instead.
There are three kinds of code we should handle:
For normal code, the CL implements goCmd() or goCmdName().
For unit tests, the CL uses testenv.GoTool() or testenv.GoToolPath().
For integration tests, the CL sets PATH=$GOROOT/bin:$PATH in cmd/dist.
Note that make.bash sets PATH=$GOROOT/bin:$PATH in the build process.
So this change is only useful when we use toolchain manually.
Updates #21875
Change-Id: I963b9f22ea732dd735363ececde4cf94a5db5ca2
Reviewed-on: https://go-review.googlesource.com/64650
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This enables support for the buildmode plugin on
ppc64le.
Fixes#20756
Change-Id: I83241ff63f9b5c366fe0496cf46a3f67d75d08ac
Reviewed-on: https://go-review.googlesource.com/55850
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
https://golang.org/cl/29394 changed to include runtime.text and
runtime.etext in ctxt.Textp as a work around.
But it seems that the CL forgot to change genasmsym.
As a result, we are generating runtime.text and runtime.etext twice.
Change-Id: If7f8faf496c1c489ffa4804da712f91a3d3f4be4
Reviewed-on: https://go-review.googlesource.com/62810
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Adddynrel does nothing on windows. We can make code don't call Adddynrel
on windows in the first place.
Change-Id: I376cc36d44a5df18bda13be57e3916ca3062f181
Reviewed-on: https://go-review.googlesource.com/62611
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
1. remove broken verification
The runtime check assumes that no-pcln symbol entry have zero value,
but the linker emit no entries if the symbol is no-pcln.
As a result, if there are no-pcln symbols at the very end of pcln
table, it will panic.
2. correct condition of export
Handle special chracters in pluginpath correcty.
Export "go.itab.*", so different plugins can share the same itab.
Fixes#18190
Change-Id: Ia4f9c51d83ce8488a9470520f1ee9432802cfc1d
Reviewed-on: https://go-review.googlesource.com/61091
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
No functional changes.
Change-Id: Ib31bb3f01b515aac6428ec61e0ef02b269623890
Reviewed-on: https://go-review.googlesource.com/62470
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Simplify the DWARF representation of structs by emitting field offsets
as constants rather than location descriptions.
This was not explicitly mentioned as an option in DWARF2. It is
mentioned in DWARF4, but isn't listed in the changes, so it's not clear
if this was always intended to work or is an undocumented change. Either
way, it should be valid DWARF4.
Change-Id: Idf7fdd397a21c8f8745673ecc77ef65afa3ffe1c
Reviewed-on: https://go-review.googlesource.com/51611
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David Chase <drchase@google.com>
