Russ Cox [Fri, 28 Feb 2014 22:13:59 +0000 (17:13 -0500)]
[release-branch.go1.2] runtime: fix crash in runtime.GoroutineProfile
This CL is not exactly a copy of the original quoted below.
This CL omits the changes made to mgc0.c in the original.
Those changes do not apply cleanly to the Go 1.2 tree,
and they were cosmetic, simplifying code that was already
doing the right thing.
To double-check that omitting the mgc0.c change has not
invalidated the fix, I have verified by hand that the test program
in issue 6946 fails without this CL and passes with this CL.
Russ Cox [Fri, 28 Feb 2014 03:43:47 +0000 (22:43 -0500)]
[release-branch.go1.2] runtime: if traceback sees a breakpoint, don't change the PC
««« CL 49580044 / 38cd458b1dfe
runtime: if traceback sees a breakpoint, don't change the PC
Changing the PC confuses gdb, because execution does not
continue where gdb expects it. Not changing the PC has the
potential to confuse a stack dump, but when running under gdb
it seems better to confuse a stack dump than to confuse gdb.
Clarify that GOROOT should only be set when using a custom install path.
Remove NetBSD from binary install page (we don't provide binaries).
Remove "What's next" links from installation instructions.
Emphasize "How to Write Go Code" page.
Fixes #6613.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/28700043
»»»
Andrew Gerrand [Wed, 13 Nov 2013 03:33:38 +0000 (14:33 +1100)]
[release-branch.go1.2] cmd/cgo: fix handling of array of pointers when using clang
««« CL 22840043 / e6794866ebeb
cmd/cgo: fix handling of array of pointers when using clang
Clang does not record the "size" field for pointer types,
so we must insert the size ourselves. We were already
doing this, but only for the case of pointer types.
For an array of pointer types, the setting of the size for
the nested pointer type was happening after the computation
of the size of the array type, meaning that the array type
was always computed as 0 bytes. Delay the size computation.
This bug happens on all Clang systems, not just FreeBSD.
Our test checked that cgo wrote something, not that it was correct.
FreeBSD's default clang rejects array[0] as a C struct field,
so it noticed the incorrect sizes. But the sizes were incorrect
everywhere.
Update testcdefs to check the output has the right semantics.
Andrew Gerrand [Fri, 1 Nov 2013 00:34:40 +0000 (11:34 +1100)]
[release-branch.go1.2] cmd/5l, runtime: fix divide for profiling tracebacks on ARM
««« CL 19910044 / 9eb64f5ef3a6
cmd/5l, runtime: fix divide for profiling tracebacks on ARM
Two bugs:
1. The first iteration of the traceback always uses LR when provided,
which it is (only) during a profiling signal, but in fact LR is correct
only if the stack frame has not been allocated yet. Otherwise an
intervening call may have changed LR, and the saved copy in the stack
frame should be used. Fix in traceback_arm.c.
2. The division runtime call adds 8 bytes to the stack. In order to
keep the traceback routines happy, it must copy the saved LR into
the new 0(SP). Change
SUB $8, SP
into
MOVW 0(SP), R11 // r11 is temporary, for use by linker
MOVW.W R11, -8(SP)
to update SP and 0(SP) atomically, so that the traceback always
sees a saved LR at 0(SP).
Fixes #6681.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/19910044
»»»
Andrew Gerrand [Fri, 1 Nov 2013 00:32:10 +0000 (11:32 +1100)]
[release-branch.go1.2] cmd/cgo: accept extra leading _ on __cgodebug_data for all object formats
««« CL 19780043 / 8b49cdda6ff4
cmd/cgo: accept extra leading _ on __cgodebug_data for all object formats
The current Windows build breakage appears to be because
the Windows code should be looking for __cgodebug_data
not ___cgodebug_data. Dodge the question everywhere by
accepting both.
Most Unix systems have their own time zone data,
so we almost never get far enough in the list to
discover that we cannot fall back to the zip file.
Adjust testing to exercise the final fallback.
Plan 9 and Windows were already correct
(and are the main users of the zip file).
This CL restores the Go 1.1.2 semantics for os.File's Readdir method.
The code in Go 1.1.2 was rewritten mainly because it looked buggy.
This new version attempts to be clearer but still provide the 1.1.2 results.
The important diff is not this CL's version against tip but this CL's version
against Go 1.1.2.
Go 1.1.2:
names, err := f.Readdirnames(n)
fi = make([]FileInfo, len(names))
for i, filename := range names {
fip, err := Lstat(dirname + filename)
if err == nil {
fi[i] = fip
} else {
fi[i] = &fileStat{name: filename}
}
}
return fi, err
This CL:
names, err := f.Readdirnames(n)
fi = make([]FileInfo, len(names))
for i, filename := range names {
fip, lerr := lstat(dirname + filename)
if lerr != nil {
fi[i] = &fileStat{name: filename}
continue
}
fi[i] = fip
}
return fi, err
The changes from Go 1.1.2 are stylistic, not semantic:
1. Use lstat instead of Lstat, for testing (done before this CL).
2. Make error handling in loop body look more like an error case.
3. Use separate error variable name in loop body, to be clear
we are not trying to influence the final return result.
Some versions of clang generate DWARF 4-format attributes
even when using -gdwarf-2. We don't care much about the
values, but we do need to be able to parse past them.
This fixes a bug in Go 1.2 rc2 reported via private mail using
a near-tip version of clang.
Andrew Gerrand [Fri, 1 Nov 2013 00:22:39 +0000 (11:22 +1100)]
[release-branch.go1.2] cmd/cgo: stop using -fno-eliminate-unused-debug-types
««« CL 18850043 / 5ef4bf9eb256
cmd/cgo: stop using -fno-eliminate-unused-debug-types
This flag was added in January 2010, in CL 181102, to fix issue 497.
(Numbers were just shorter back then.) The fix was for OS X machines
and the llvm-gcc frontend.
In July 2011 we had to change the way we get enum values, because
there were no flags available to force Xcode's llvm-gcc to include the
enum names and values in DWARF debug output.
We now use clang, not llvm-gcc, on OS X machines.
Earlier versions of clang printed a warning about not knowing the flag.
Newer versions of clang now make that an error.
That is:
- The flag was added for OS X machines.
- The flag is no longer necessary on OS X machines.
- The flag now breaks some OS X machines.
Remove it.
I have run the original program from issue 497 successfully
without the flag on both OS X and Linux machines.
The case can happen when starttheworld is calling acquirep
to get things moving again and acquirep gets preempted.
The stack trace is in golang.org/issue/6644.
It is difficult to build a short test case for this, but
the person who reported issue 6644 confirms that this
solves the problem.
Fixes #6644.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/18740044
»»»
singleStringReplacer had a bug where if a string was replaced
at the beginning and no output had yet been produced into the
temp buffer before matching ended, an invalid nil check (used
as a proxy for having matched anything) meant it always
returned its input.
Fixes #6659
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/16880043
»»»
Andrew Gerrand [Fri, 1 Nov 2013 00:09:06 +0000 (11:09 +1100)]
[release-branch.go1.2] crypto/tls: advertise support for RSA+SHA1 in TLS 1.2 handshake.
««« CL 15650043 / 29d3ab5ced5a
crypto/tls: advertise support for RSA+SHA1 in TLS 1.2 handshake.
Despite SHA256 support being required for TLS 1.2 handshakes, some
servers are aborting handshakes that don't offer SHA1 support.
This change adds support for signing TLS 1.2 ServerKeyExchange messages
with SHA1. It does not add support for signing TLS 1.2 client
certificates with SHA1 as that would require the handshake to be
buffered.
Fixes #6618.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/15650043
»»»
Andrew Gerrand [Fri, 1 Nov 2013 00:05:17 +0000 (11:05 +1100)]
[release-branch.go1.2] cmd/cgo: stop using compiler error message text to analyze C names
««« CL 15070043 / 90a628ac54ed
cmd/cgo: stop using compiler error message text to analyze C names
The old approach to determining whether "name" was a type, constant,
or expression was to compile the C program
name;
and scan the errors and warnings generated by the compiler.
This requires looking for specific substrings in the errors and warnings,
which ties the implementation to specific compiler versions.
As compilers change their errors or drop warnings, cgo breaks.
This happens slowly but it does happen.
Clang in particular (now required on OS X) has a significant churn rate.
The new approach compiles a slightly more complex program
that is either valid C or not valid C depending on what kind of
thing "name" is. It uses only the presence or absence of an error
message on a particular line, not the error text itself. The program is:
// error if and only if name is undeclared
void f1(void) { typeof(name) *x; }
// error if and only if name is not a type
void f2(void) { name *x; }
// error if and only if name is not an integer constant
void f3(void) { enum { x = (name)*1 }; }
I had not been planning to do this until Go 1.3, because it is a
non-trivial change, but it fixes a real Xcode 5 problem in Go 1.2,
and the new code is easier to understand than the old code.
It should be significantly more robust.
Andrew Gerrand [Thu, 31 Oct 2013 23:51:42 +0000 (10:51 +1100)]
[release-branch.go1.2] runtime: remove nomemprof
««« CL 14695044 / 35d5bae6aac8
runtime: remove nomemprof
Nomemprof seems to be unneeded now, there is no recursion.
If the recursion will be re-introduced, it will break loudly by deadlocking.
Fixes #6566.
Alberto García Hierro [Thu, 17 Oct 2013 16:02:32 +0000 (09:02 -0700)]
database/sql: make tests repeatable with -cpu=n,n
New test added in CL 14611045 causes a deadlock when
running the tests with -cpu=n,n because the fakedb
driver always waits when opening a new connection after
running TestConnectionLeak. Reset its state after.
Robert Griesemer [Wed, 16 Oct 2013 23:16:54 +0000 (16:16 -0700)]
spec: clarify re-use of underlying arrays in slice operations
Please note the slight rewording for append: The spec now
requires that append reuses the underlying array if it is
sufficiently large. Per majority sentiment.
This is technically a language change but the current
implementation always worked this way.
Alberto García Hierro [Wed, 16 Oct 2013 16:22:57 +0000 (09:22 -0700)]
database/sql: Fix connection leak and potential deadlock
CL 10726044 introduced a race condition which causes connections
to be leaked under certain circumstances. If SetMaxOpenConns is
used, the application eventually deadlocks. Otherwise, the number
of open connections just keep growing indefinitely.
Russ Cox [Tue, 15 Oct 2013 19:00:48 +0000 (15:00 -0400)]
cmd/cgo: print the builtin prolog after the per-file preamble
The preamble may want to #define some special symbols
and then #include <sys/types.h> itself. The builtin prolog
also #includes <sys/types.h>, which would break such a
preamble (because the second #include will be a no-op).
The use of sys/types.h in the builtin prolog is new since Go 1.1,
so this should preserve the semantics of more existing cgo
code than we would otherwise.
It also fixes src/pkg/syscall/mkall.sh's use of go tool cgo -godefs
on some Linux systems.
undone because the change slows down profile collection
significantly and unpredictable at times (see comments
at https://golang.org/cl/14231047 for details)
««« original CL description
runtime: collect profiles even while on g0 stack