Signed-off-by: Eric Engestrom <eric@engestrom.ch>
Change-Id: I91873aaebf79bdf1c00d38aacc1a1fb8d79656a7
Reviewed-on: https://go-review.googlesource.com/21433
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
It is valid for io.Reader to return (n, io.EOF) where n is positive.
The unit test should not fail if io.EOF is returned when read until
the end.
Change-Id: I7b918e3cc03db8b90c8aa58f4c0f7806a1d4af7e
Reviewed-on: https://go-review.googlesource.com/21307
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
These new methods help find the compilation unit to pass to the
LineReader method in order to find the line information for a PC.
The Ranges method also helps identify the specific function for a PC,
needed to determine the function name.
This uses the .debug.ranges section if necessary, and changes the object
file format packages to pass in the section contents if available.
Change-Id: I5ebc3d27faaf1a126ffb17a1e6027efdf64af836
Reviewed-on: https://go-review.googlesource.com/20769
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.
This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:
$ perl -i -npe 's,^(\s*// .+[a-z]\.) +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.) +([A-Z])')
$ go test go/doc -update
Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a subset of https://golang.org/cl/20022 with only the copyright
header lines, so the next CL will be smaller and more reviewable.
Go policy has been single space after periods in comments for some time.
The copyright header template at:
https://golang.org/doc/contribute.html#copyright
also uses a single space.
Make them all consistent.
Change-Id: Icc26c6b8495c3820da6b171ca96a74701b4a01b0
Reviewed-on: https://go-review.googlesource.com/20111
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This future-proofs the Chdr64 structure against later versions of ELF
defining this field and declutters the documentation without changing
the layout of the struct.
This structure does not exist in the current release, so this change
is safe.
Change-Id: I239aad7243ddaf063a1f8cd521d8a50b30413281
Reviewed-on: https://go-review.googlesource.com/18028
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This adds support for compressed ELF sections. This compression is
treated as a framing issue and hence the package APIs all
transparently decompress compressed sections. This requires some
subtlety for (*Section).Open, which returns an io.ReadSeeker: since
the decompressed data comes from an io.Reader, this commit introduces
a Reader-to-ReadSeeker adapter that is efficient for common uses of
Seek and does what it can otherwise.
Fixes#11773.
Change-Id: Ic0cb7255a85cadf4c1d15fb563d5a2e89dbd3c36
Reviewed-on: https://go-review.googlesource.com/17341
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
GCC and LLVM support zlib-compressing DWARF debug sections (and
there's some evidence that this may be happening by default in some
circumstances now).
Add support for reading compressed DWARF sections. Since ELF
relocations apply to the decompressed data, decompression is done
before applying relocations. Since relcations are applied by
debug/elf, decompression must also be handled there.
Note that this is different from compressed ELF sections, which is a
more general mechanism used by very recent versions of GCC.
Updates #11773.
Change-Id: I3f4bf1b04d0802cc1e8fcb7c2a5fcf6c467c5089
Reviewed-on: https://go-review.googlesource.com/17340
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Simplify slice/map literal expressions.
Caught with gofmt -d -s, fixed with gofmt -w -s
Reformatted some expressions to improve readability.
Change-Id: Iaf123e6bd49162ec45c59297ad3b002ca59443bc
Reviewed-on: https://go-review.googlesource.com/13850
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The original version of applyRelocationsARM was added in
http://golang.org/cl/7266. It was added to fix the ARM build, which
had been broken by http://golang.org/cl/6780.
Before CL 6780, there was no relocation processing for ARM. CL 6780
changed the code to require relocation processing for every supported
target. CL 7266 fixed the ARM build by adding a relocation processing
function, but in fact no actual processing was done. The code only
looked for REL32 relocations, but ARM debug info has no such
relocations. The test case added in CL 7266 doesn't have any either.
This didn't matter because no relocation processing was required on
ARM, at least not for GCC-generated debug info. GCC generates ABS32
relocations, but only against section symbols which have the value 0.
Therefore, the addition done by correct handling of ABS32 doesn't
change anything.
Clang, however, generates ABS32 relocations against local symbols,
some of which have non-zero values. For those, we need to handle
ABS32 relocations.
This patch corrects the CL 7266 to look for ABS32 relocations instead
of REL32 relocations. The code was already written to correctly
handle ABS32 relocations, it just mistakenly said REL32.
This is the ARM equivalent of https://golang.org/cl/96680045, which
fixed the same problem in the same way for clang on 386.
With this patch, clang-3.5 can be used to build Go on ARM GNU/Linux.
Fixes#8980.
Change-Id: I0c2d72eadfe6373bde99cd03eee40de6a582dda1
Reviewed-on: https://go-review.googlesource.com/11222
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
To return DWARF attribute values, debug/dwarf maps the DWARF attribute
value classes to Go types. Unfortunately, this mapping is ambiguous in
a way that makes it impossible to correctly interpret some DWARF
attributes as of DWARF 4. For example, AttrStartScope can be either a
constant or a rangelistptr. The attribute is interpreted differently
depending on its class, but debug/dwarf maps both classes to int64, so
the caller can't distinguish them from the Go type.
AttrDataMemberLocation is similar.
To address this, this change adds a field to type Field that indicates
the exact DWARF attribute value class of that field's value. This
makes it possible to distinguish value classes that can't be
distinguished by their Go type alone.
The root of this type ambiguity was DWARF itself. For example, DWARF 2
made no distinction between constants that were just constants and
constants that were section offsets because no attribute could have
both meanings. Hence, the single int64 type was sufficient. To avoid
introducing just another layer of ambiguity, this change takes pains
to canonicalize ambiguous classes in DWARF 2 and 3 files into the
unambiguous classes of DWARF 4.
Of course, there's no guarantee that future DWARF versions won't do
the same thing again and further subdivide the DWARF 4 classes. This
change gets ahead of this somewhat by distinguishing the various *ptr
classes even though the encoding does not. If there's some other form
of split, we can handle this in a backwards-compatible way by
introducing, for example, a Class5 field and type.
Change-Id: I4ef96d1223b0fd7f96ecf44fcc0e704a36af02b4
Reviewed-on: https://go-review.googlesource.com/8502
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This change adds the minimum necessary to implement applyRelocations.
For adg, this code uses the switch statement.
Change-Id: I0989daab8d0e36c2a4f6a315ced258b832744616
Reviewed-on: https://go-review.googlesource.com/7266
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: Ia6f9bd77a3d4250339dcb054edc76942864dd358
Reviewed-on: https://go-review.googlesource.com/6781
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Previously, different DWARF sections had relocations applied in very
different ways. .debug_info was relocated, but only on x86-64 and 386
and using hard-coded relocation section names instead of relocation
links. .debug_abbrev and .debug_str were never relocated (which is
excusable because they shouldn't need it). .debug_types sections were
relocated on all architectures and found their relocation section
using a relocation link because section names could be ambiguous.
Simplify all of this so that every DWARF section that has a linked
relocation section gets those relocations applied.
This prepares this code to load .debug_line sections without the need
for yet more ad hoc relocation logic.
Change-Id: Ia00ac8e656b22f22bb31a5f6ef9b0f23cda64d19
Reviewed-on: https://go-review.googlesource.com/6780
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This brings dev.power64 up-to-date with the current tip of
default. go_bootstrap is still panicking with a bad defer
when initializing the runtime (even on amd64).
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/152570049
This also removes pkg/runtime/traceback_lr.c, which was ported
to Go in an earlier commit and then moved to
runtime/traceback.go.
Reviewer: rsc@golang.org
rsc: LGTM
