This fixes the bug in which the linker reports "missing Go
type information" when a -X option refers to a symbol that is
not used.
Fixes#8821.
LGTM=rsc
R=rsc, r
CC=golang-codereviews
https://golang.org/cl/151000043
The extra-clever code in Sincos is trying to do
if v&2 == 0 {
mask = 0xffffffffffffffff
} else {
mask = 0
}
It does this by turning v&2 into a float64 X0 and then using
MOVSD $0.0, X3
CMPSD X0, X3, 0
That CMPSD is defined to behave like:
if X0 == X3 {
X3 = 0xffffffffffffffff
} else {
X3 = 0
}
which gives the desired mask in X3. The goal in using the
CMPSD was to avoid a conditional branch.
This code fails when called from a PortAudio callback.
In particular, the failure behavior is exactly as if the
CMPSD always chose the 'true' execution.
Notice that the comparison X0 == X3 is comparing as
floating point values the 64-bit pattern v&2 and the actual
floating point value zero. The only possible values for v&2
are 0x0000000000000000 (floating point zero)
and 0x0000000000000002 (floating point 1e-323, a denormal).
If they are both comparing equal to zero, I conclude that
in a PortAudio callback (whatever that means), the processor
is running in "denormals are zero" mode.
I confirmed this by placing the processor into that mode
and running the test case in the bug; it produces the
incorrect output reported in the bug.
In general, if a Go program changes the floating point math
modes to something other than what Go expects, the math
library is not going to work exactly as intended, so we might
be justified in not fixing this at all.
However, it seems reasonable that the client code might
have expected "denormals are zero" mode to only affect
actual processing of denormals. This code has produced
what is in effect a gratuitous denormal by being extra clever.
There is nothing about the computation being requested
that fundamentally requires a denormal.
It is also easy to do this computation in integer math instead:
mask = ((v&2)>>1)-1
Do that.
For the record, the other math tests that fail if you put the
processor in "denormals are zero" mode are the tests for
Frexp, Ilogb, Ldexp, Logb, Log2, and FloatMinMax, but all
fail processing denormal inputs. Sincos was the only function
for which that mode causes incorrect behavior on non-denormal inputs.
The existing tests check that the new assembly is correct.
There is no test for behavior in "denormals are zero" mode,
because I don't want to add assembly to change that.
Fixes#8623.
LGTM=josharian
R=golang-codereviews, josharian
CC=golang-codereviews, iant, r
https://golang.org/cl/151750043
go test's handling of _test.go files when the entire
package's set of files has no Test functions has varied
over the past few releases. There are a few interesting
cases (all contain no Test functions):
(1) x_test.go has syntax errors
(2) x_test.go has type errors
(3) x_test.go has runtime errors (say, a func init that panics)
In Go 1.1, tests with (1) or (2) failed; (3) passed.
In Go 1.2, tests with (1) or (2) failed; (3) passed.
In Go 1.3, tests with (1) failed; (2) or (3) passed.
After this CL, tests with (1), (2), or (3) all fail.
This is clearly a corner case, but it seems to me that
the behavior of the test should not change if you
add or remove a line like
func TestAlwaysPasses(t *testing.T) {}
That implies that the _test.go files must always
be built and always be imported into the test binary.
Doing so means that (1), (2), and (3) must all fail.
Fixes#8337.
LGTM=iant
R=golang-codereviews, iant
CC=adg, golang-codereviews, r
https://golang.org/cl/150980043
From issue 7967 I learned:
1) yacc accepts either 'x' or "x" to mean token value 0x78
2) yacc also accepts 'xyz' and "XYZ" to mean token value 0x78
Use strconv.Unquote to simplify the handling of quoted
strings and check that each has only one rune.
Although this does clean things up, it makes 'x' and "x"
treated as different internally (now they are stored as
`'x'` and `"x"`; before they were both ` x`). Grammars that
use both interchangeably will now die with an error
similar to the one from issue 7967:
yacc bug -- cannot have 2 different Ts with same value
"+" and '+'
The echoing of the quotes should make clear what is going on.
The other semantic change caused by using strconv.Unquote
is that '\"' and "\'" are no longer valid. Like in Go, they must be
spelled without the backslash: '"' and "'".
On the other hand, now yacc and Go agree about what character
and string literals mean.
LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/149110043
The one line that you can't test easily was broken.
This manifested as a failure of a pre-existing test
in test.bash but I didn't notice it (there are a few other
long-standing failures that need to be fixed).
TBR=r
CC=golang-codereviews
https://golang.org/cl/146340044
Today, 'go build -a my/pkg' and 'go install -a my/pkg'
recompile not just my/pkg and all its dependencies that
you wrote but also the standard library packages.
Recompiling the standard library is problematic on
some systems because the installed copy is not writable.
The -a behavior means that you can't use 'go install -a all'
or 'go install -a my/...' to rebuild everything after a Go
release - the rebuild stops early when it cannot overwrite
the installed standard library.
During development work, however, you do want install -a
to rebuild everything, because anything might have changed.
Resolve the conflict by making the behavior of -a depend
on whether we are using a released copy of Go or a devel copy.
In the release copies, -a no longer applies to the standard library.
In the devel copies, it still does.
This is the latest in a long line of refinements to the
"do I build this or not" logic. It is surely not the last.
Fixes#8290.
LGTM=r
R=golang-codereviews, r, tracey.brendan
CC=adg, golang-codereviews, iant
https://golang.org/cl/151730045
This fixes the test/linkx.go test, which does not run by default.
(Issue 4139 is about fixing that.)
Fixes#8806.
LGTM=r
R=golang-codereviews, r
CC=bradfitz, golang-codereviews, iant
https://golang.org/cl/145420043
Also rebuild doc.go; was stale, so contains extra changes.
Fixes#8677.
LGTM=r
R=golang-codereviews, r
CC=golang-codereviews, iant
https://golang.org/cl/148170043
While we are here, remove undocumented, meaningless test -file flag.
Fixes#7724.
LGTM=r
R=golang-codereviews, r
CC=golang-codereviews, iant
https://golang.org/cl/149070043
Fix by atom (from CL 89190044), comment and test by me.
Fixes#6823.
LGTM=crawshaw
R=golang-codereviews, crawshaw
CC=0xe2.0x9a.0x9b, adg, golang-codereviews, iant, r
https://golang.org/cl/148180043
If you say 'go get -v' you get extra information when import
paths are not of the expected form.
If you say 'go get -v src/rsc.io/pdf' the message says that
src/rsc.io/pdf does not contain a hostname, which is incorrect.
The problem is that it does not begin with a hostname.
Fixes#7432.
LGTM=r
R=golang-codereviews, r
CC=bradfitz, golang-codereviews, iant
https://golang.org/cl/144650043
If you do 'go get -u rsc.io/pdf' and then rsc.io/pdf's redirect
changes to point somewhere else, after this CL a later
'go get -u rsc.io/pdf' will tell you that.
Fixes#8548.
LGTM=iant
R=golang-codereviews, iant
CC=adg, golang-codereviews, n13m3y3r, r
https://golang.org/cl/147170043
The pattern was only working if the checkout had
already been done, but the code was trying to make
it work even the first time. Test and fix.
Fixes#8335.
LGTM=r
R=golang-codereviews, r
CC=golang-codereviews, iant
https://golang.org/cl/146310043
Need to restore the g register. Somehow this line vaporized from
CL 144130043. Also cgo_topofstack -> _cgo_topofstack, that vaporized also.
TBR=rsc
CC=golang-codereviews
https://golang.org/cl/150940044
During a cgo call, the stack can be copied. This copy invalidates
the pointer that cgo has into the return value area. To fix this
problem, pass the address of the location containing the stack
top value (which is in the G struct). For cgo functions which
return values, read the stktop before and after the cgo call to
compute the adjustment necessary to write the return value.
Fixes#8771
LGTM=iant, rsc
R=iant, rsc, khr
CC=golang-codereviews
https://golang.org/cl/144130043
Not sure why they used empty.s and all these other
packages were special cased in cmd/go instead.
Add them to the list.
This avoids problems with net .s files being compiled
with gcc in cgo mode and gcc not supporting // comments
on ARM.
Not a problem with bytes, but be consistent.
The last change fixed the ARM build but broke the Windows build.
Maybe *this* will make everyone happy. Sigh.
TBR=iant
CC=golang-codereviews
https://golang.org/cl/144530046
In cgo mode it gets passed to gcc, and on ARM
it appears that gcc does not support // comments.
TBR=iant
CC=golang-codereviews
https://golang.org/cl/142640043
Fixes linux builds (_vdso); may fix others.
I can at least cross-compile cmd/go for every
implemented system now.
TBR=iant
CC=golang-codereviews
https://golang.org/cl/142630043
Should fix the Windows build. Untested.
on Windows, args are made by src/os/exec_windows.go, not package runtime.
runtime·goargs has if(Windows) return;
The two init funcs in pkg os were conflicting, with the second
overwriting Args back to an empty slice.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/143540044
Corrections due to new strict type rules for data+bss.
Also disable misc/cgo/cdefstest since you can't compile C code anymore.
TBR=iant
CC=golang-codereviews
https://golang.org/cl/148050044
Previous behavior was undocumented and inconsistent. Now it is documented
and consistent and measures the input size, since that makes more sense
when talking about %q and %x. For %s the change has no effect.
Fixes#8151.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/144540044
In linker, refuse to write conservative (array of pointers) as the
garbage collection type for any variable in the data/bss GC program.
In the linker, attach the Go type to an already-read C declaration
during dedup. This gives us Go types for C globals for free as long
as the cmd/dist-generated Go code contains the declaration.
(Most runtime C declarations have a corresponding Go declaration.
Both are bss declarations and so the linker dedups them.)
In cmd/dist, add a few more C files to the auto-Go-declaration list
in order to get Go type information for the C declarations into the linker.
In C compiler, mark all non-pointer-containing global declarations
and all string data as NOPTR. This allows them to exist in C files
without any corresponding Go declaration. Count C function pointers
as "non-pointer-containing", since we have no heap-allocated C functions.
In runtime, add NOPTR to the remaining pointer-containing declarations,
none of which refer to Go heap objects.
In runtime, also move os.Args and syscall.envs data into runtime-owned
variables. Otherwise, in programs that do not import os or syscall, the
runtime variables named os.Args and syscall.envs will be missing type
information.
I believe that this CL eliminates the final source of conservative GC scanning
in non-SWIG Go programs, and therefore...
Fixes#909.
LGTM=iant
R=iant
CC=golang-codereviews
https://golang.org/cl/149770043
