Also move chatty recent additions to -v -v.
For what it's worth:
$ go build -o /dev/null -ldflags -v cmd/go
...
0.87 pclntab=1110836 bytes, funcdata total 69700 bytes
...
$
This broke the ELF builds last time because I tried to dedup
the funcdata in case the same funcdata was pointed at by
multiple functions. That doesn't currently happen, so I've
removed that test.
If we start doing bitmap coalescing we'll need to figure out
how to measure the size more carefully, but I think at that
point the bitmaps will be an extra indirection away from the
funcdata anyway, so the dedup I used before wouldn't help.
R=ken2
CC=golang-dev
https://golang.org/cl/12269043
src/cmd/ld/lib.c:1379 set and not used: p
src/cmd/ld/lib.c:1426 format mismatch 6llux INT, arg 3
src/cmd/ld/lib.c:1437 format mismatch 6llux INT, arg 3
src/cmd/ld/lib.c:1456 format mismatch 6llux INT, arg 3
src/cmd/ld/lib.c:1477 format mismatch 6llux INT, arg 3
src/cmd/ld/lib.c:1459 set and not used: started
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/11615044
This CL introduces a FUNCDATA number for runtime-specific
garbage collection metadata, changes the C and Go compilers
to emit that metadata, and changes the runtime to expect it.
The old pseudo-instructions that carried this information
are gone, as is the linker code to process them.
R=golang-dev, dvyukov, cshapiro
CC=golang-dev
https://golang.org/cl/11406044
whose argument size is unknown (C vararg functions, and
assembly code without an explicit specification).
We used to use 0 to mean "unknown" and 1 to mean "zero".
Now we use ArgsSizeUnknown (0x80000000) to mean "unknown".
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/11590043
This should fix the Windows build, or at least
what's breaking it at the moment.
Fixes#5904.
TBR=golang-dev
CC=golang-dev
https://golang.org/cl/11519044
Design at http://golang.org/s/go12symtab.
This enables some cleanup of the garbage collector metadata
that will be done in future CLs.
This CL does not move the old symtab and pclntab back into
an unmapped section of the file. That's a bit tricky and will be
done separately.
Fixes#4020.
R=golang-dev, dave, cshapiro, iant, r
CC=golang-dev, nigeltao
https://golang.org/cl/11085043
USEFIELD is a special kind of NOP, so treat it like a NOP
when generating the pc-ln table.
There are more invasive fixes that could be applied here.
I am going for minimum number of lines changed.
The smallest test case we know of is five distinct Go files
in four packages, and the bug only happens with
GOEXPERIMENT=fieldtrack enabled, which we don't
normally build with, so the test would never run
meaningfully anyway.
Fixes#5762.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/10495044
Remove unnecessary ( ) around == in && clause.
Add { } around multiline if body, even though it's one statement.
Add runtime: prefix to printed errors.
R=cshapiro, iant
CC=golang-dev
https://golang.org/cl/9685047
A nosplits was assumed to have no argument information and no
pointer map. However, nosplits created by the linker often
have both. This change uses the pointer map size as an
alternate source of argument size when processing a nosplit.
In addition, the symbol table construction pointer map size
and argument size consistency check is strengthened. If a
nptrs is greater than 0 it must be equal to the number of
argument words.
R=golang-dev, khr, khr
CC=golang-dev
https://golang.org/cl/9666047
With this change the compiler emits a bitmap for each function
covering its stack frame arguments area. If an argument word
is known to contain a pointer, a bit is set. The garbage
collector reads this information when scanning the stack by
frames and uses it to ignores locations known to not contain a
pointer.
R=golang-dev, bradfitz, daniel.morsing, dvyukov, khr, khr, iant, cshapiro
CC=golang-dev
https://golang.org/cl/9223046
This is needed for SWIG when linking in internal mode. In
internal mode if a symbol was cgo_import_static we used to
forget that it was also cgo_import_dynamic.
R=rsc, r
CC=golang-dev
https://golang.org/cl/9080043
Some variables declared in C could end up as undefined symbols
in the final binary and have null address.
Fixes#5114.
Fixes#5227.
R=golang-dev, iant, ajstarks, dave, r
CC=golang-dev
https://golang.org/cl/8602044
Permits specifying the linker to use, and trailing flags to
pass to that linker, when linking in external mode. External
mode linking is used when building a package that uses cgo, as
described in the cgo docs.
Also document -linkmode and -tmpdir.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8225043
While we're here, downgrade DWARF to version 2.
We're not using any version 3 features, and OS X gdb
only supports version 2.
Fixes#3436.
R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/7891044
Many thanks to Elias Naur for finding this with Valgrind on Linux.
Perhaps this is what is breaking the windows/amd64 builder.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7595044
lib9: fix runcmd, removeall, and tempdir functions
cmd/dist: Include run_plan9.c and tempdir_plan9.c
from lib9 for build, and in general consider
file names containing "plan9" for building.
cmd/ld: provide function args for the new functions
from lib9.
R=rsc, rminnich, ality, bradfitz
CC=golang-dev
https://golang.org/cl/7666043
The sticking point on 386 has been the "PC relative" relocations
used to point the garbage collection metadata at the type info.
These aren't in the code segment, and I don't trust that the linker
isn't doing something special that would be okay in code but
not when interpreting the pointers as data (for example, a PLT
jump table would be terrible).
Solve the problem in two steps:
1. Handle "PC relative" relocations within a section internally,
so that the external linker never sees them.
2. Move the gcdata and gcbss tables into the rodata section,
where the type information lives, so that the relocations can
be handled internally.
(To answer the obvious question, we make the gc->type
references relative so that they need not be relocated
individually when generating a shared object file.)
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7629043
- Introduce MaxAlign constant and use in data layout
and ELF section header.
- Allow up to 16-byte alignment for large objects
(will help Keith's hash changes).
- Emit ELF symbol for .rathole (global /dev/null used by 8c).
- Invoke gcc with -m32/-m64 as appropriate.
- Don't invoke gcc if writing the .o file failed.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7563045
Still to do: non-linux and non-amd64.
It may work on other ELF-based amd64 systems too, but untested.
"go test -ldflags -hostobj $GOROOT/misc/cgo/test" passes.
Much may yet change, but this seems a reasonable checkpoint.
R=iant
CC=golang-dev
https://golang.org/cl/7369057
This CL changes the encoding used for the Go symbol table,
stored in the binary and used at run time. It does not change
any of the semantics or structure: the bits are just packed
a little differently.
The comment at the top of runtime/symtab.c describes the new format.
Compared to the Go 1.0 format, the main changes are:
* Store symbol addresses as full-pointer-sized host-endian values.
(For 6g, this means addresses are 64-bit little-endian.)
* Store other values (frame sizes and so on) varint-encoded.
The second change more than compensates for the first:
for the godoc binary on OS X/amd64, the new symbol table
is 8% smaller than the old symbol table (1,425,668 down from 1,546,276).
This is a required step for allowing the host linker (gcc) to write
the final Go binary, since it will have to fill in the symbol address slots
(so the slots must be host-endian) and on 64-bit systems it may
choose addresses above 4 GB.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7403054
Previously, the func structure contained an inaccurate value for
the args member and a 0 value for the locals member.
This change populates the func structure with args and locals
values computed by the compiler. The number of args was
already available in the ATEXT instruction. The number of
locals is now passed through in the new ALOCALS instruction.
This change also switches the unit of args and locals to be
bytes, just like the frame member, instead of 32-bit words.
R=golang-dev, bradfitz, cshapiro, dave, rsc
CC=golang-dev
https://golang.org/cl/7399045
A step toward a fix for issue 4069.
To allow linking with arbitrary host object files, add a linker mode
that can generate a host object file instead of an executable.
Then the host linker can be invoked to generate the final executable.
This CL adds a new -hostobj flag that instructs the linker to write
a host object file instead of an executable.
That is, this works:
go tool 6g x.go
go tool 6l -hostobj -o x.o x.6
ld -e _rt0_amd64_linux x.o
./a.out
as does:
go tool 8g x.go
go tool 8l -hostld ignored -o x.o x.8
ld -m elf_i386 -e _rt0_386_linux x.o
./a.out
Because 5l was never updated to use the standard relocation scheme,
it will take more work to get this working on ARM.
This is a checkpoint of the basic functionality. It does not work
with cgo yet, and cgo is the main reason for the change.
The command-line interface will likely change too.
The gc linker has other information that needs to be returned to
the caller for use when invoking the host linker besides the single
object file.
R=iant, iant
CC=golang-dev
https://golang.org/cl/7060044
There's no b in race detector.
The new flag matches the one in the go command
(go test -race math).
R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/7072043
This CL adds a flag parser that matches the semantics of Go's
package flag. It also changes the linkers and compilers to use
the new flag parser.
Command lines that used to work, like
8c -FVw
6c -Dfoo
5g -I/foo/bar
now need to be split into separate arguments:
8c -F -V -w
6c -D foo
5g -I /foo/bar
The new spacing will work with both old and new tools.
The new parser also allows = for arguments, as in
6c -D=foo
5g -I=/foo/bar
but that syntax will not work with the old tools.
In addition to matching standard Go binary flag parsing,
the new flag parser generates more detailed usage messages
and opens the door to long flag names.
The recently added gc flag -= has been renamed -complete.
R=remyoudompheng, daniel.morsing, minux.ma, iant
CC=golang-dev
https://golang.org/cl/7035043
More cleanup in preparation for fixing issue 4069.
This CL replaces the three nearly identical copies of the
asmb ELF code with a single asmbelf function in elf.c.
In addition to the ELF code movement, remove the elfstr
array in favor of a simpler lookup, and identify sections by
name throughout instead of computing fragile indices.
The CL also replaces the three nearly identical copies of the
genasmsym code with a single genasmsym function in lib.c.
The ARM linker still compiles and generates binaries,
but I haven't tested the binaries. They may not work.
R=ken2
CC=golang-dev
https://golang.org/cl/7062047
The 0-length part is fine, but some callers that write 0 bytes
also pass nil as the data pointer, and the Plan 9 kernel kills the
process with 'invalid address in sys call' in that case.
R=ken2
CC=golang-dev
https://golang.org/cl/6862051
Keith Randall
Russ Cox
Brad Fitzpatrick
David du Colombier
Ian Lance Taylor
Dave Cheney
Shenghou Ma
Carl Shapiro
Alex Brainman
Rémy Oudompheng
Akshat Kumar
Elias Naur