to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We tell the user to file a bug report on LLVM right now, and
SIGPIPE isn't LLVM's fault so our error message is wrong.
Allows frontends to detect SIGPIPE from writing to closed readers.
This can be seen commonly from piping into head, tee, or split.
Fixes PR25349, rdar://problem/14285346, b/77310947
Reviewers: jfb
Reviewed By: jfb
Subscribers: majnemer, kristina, llvm-commits, thakis, srhines
Differential Revision: https://reviews.llvm.org/D53000
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344372 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Before this patch, signal handling wasn't signal safe. This leads to real-world
crashes. It used ManagedStatic inside of signals, this can allocate and can lead
to unexpected state when a signal occurs during llvm_shutdown (because
llvm_shutdown destroys the ManagedStatic). It also used cl::opt without custom
backing storage. Some de-allocation was performed as well. Acquiring a lock in a
signal handler is also a great way to deadlock.
We can't just disable signals on llvm_shutdown because the signals might do
useful work during that shutdown. We also can't just disable llvm_shutdown for
programs (instead of library uses of clang) because we'd have to then mark the
pointers as not leaked and make sure all the ManagedStatic uses are OK to leak
and remain so.
Move all of the code to lock-free datastructures instead, and avoid having any
of them in an inconsistent state. I'm not trying to be fancy, I'm not using any
explicit memory order because this code isn't hot. The only purpose of the
atomics is to guarantee that a signal firing on the same or a different thread
doesn't see an inconsistent state and crash. In some cases we might miss some
state (for example, we might fail to delete a temporary file), but that's fine.
Note that I haven't touched any of the backtrace support despite it not
technically being totally signal-safe. When that code is called we know
something bad is up and we don't expect to continue execution, so calling
something that e.g. sets errno is the least of our problems.
A similar patch should be applied to lib/Support/Windows/Signals.inc, but that
can be done separately.
Fix r332428 which I reverted in r332429. I originally used double-wide CAS
because I was lazy, but some platforms use a runtime function for that which
thankfully failed to link (it would have been bad for signal handlers
otherwise). I use a separate flag to guard the data instead.
<rdar://problem/28010281>
Reviewers: dexonsmith
Subscribers: steven_wu, llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332496 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Before this patch, signal handling wasn't signal safe. This leads to real-world
crashes. It used ManagedStatic inside of signals, this can allocate and can lead
to unexpected state when a signal occurs during llvm_shutdown (because
llvm_shutdown destroys the ManagedStatic). It also used cl::opt without custom
backing storage. Some de-allocation was performed as well. Acquiring a lock in a
signal handler is also a great way to deadlock.
We can't just disable signals on llvm_shutdown because the signals might do
useful work during that shutdown. We also can't just disable llvm_shutdown for
programs (instead of library uses of clang) because we'd have to then mark the
pointers as not leaked and make sure all the ManagedStatic uses are OK to leak
and remain so.
Move all of the code to lock-free datastructures instead, and avoid having any
of them in an inconsistent state. I'm not trying to be fancy, I'm not using any
explicit memory order because this code isn't hot. The only purpose of the
atomics is to guarantee that a signal firing on the same or a different thread
doesn't see an inconsistent state and crash. In some cases we might miss some
state (for example, we might fail to delete a temporary file), but that's fine.
Note that I haven't touched any of the backtrace support despite it not
technically being totally signal-safe. When that code is called we know
something bad is up and we don't expect to continue execution, so calling
something that e.g. sets errno is the least of our problems.
A similar patch should be applied to lib/Support/Windows/Signals.inc, but that
can be done separately.
<rdar://problem/28010281>
Reviewers: dexonsmith
Subscribers: aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D46858
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332428 91177308-0d34-0410-b5e6-96231b3b80d8
As requested in D46858, pulling this function into its own lambda makes it
easier to read that part of the code and reason as to what's going on because
the scope it can be called from is extremely limited. We want to keep it as a
function because it's called from the two subsequent lines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332325 91177308-0d34-0410-b5e6-96231b3b80d8
Don't prepend function or data name before each comment. Split into its own NFC patch as requested in D46858.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332323 91177308-0d34-0410-b5e6-96231b3b80d8
See r331124 for how I made a list of files missing the include.
I then ran this Python script:
for f in open('filelist.txt'):
f = f.strip()
fl = open(f).readlines()
found = False
for i in xrange(len(fl)):
p = '#include "llvm/'
if not fl[i].startswith(p):
continue
if fl[i][len(p):] > 'Config':
fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
found = True
break
if not found:
print 'not found', f
else:
open(f, 'w').write(''.join(fl))
and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.
No intended behavior change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331184 91177308-0d34-0410-b5e6-96231b3b80d8
This is the second part of recommit of r325224. The previous part was
committed in r325426, which deals with C++ memory allocation. Solution
for C memory allocation involved functions `llvm::malloc` and similar.
This was a fragile solution because it caused ambiguity errors in some
cases. In this commit the new functions have names like `llvm::safe_malloc`.
The relevant part of original comment is below, updated for new function
names.
Analysis of fails in the case of out of memory errors can be tricky on
Windows. Such error emerges at the point where memory allocation function
fails, but manifests itself when null pointer is used. These two points
may be distant from each other. Besides, next runs may not exhibit
allocation error.
In some cases memory is allocated by a call to some of C allocation
functions, malloc, calloc and realloc. They are used for interoperability
with C code, when allocated object has variable size and when it is
necessary to avoid call of constructors. In many calls the result is not
checked for null pointer. To simplify checks, new functions are defined
in the namespace 'llvm': `safe_malloc`, `safe_calloc` and `safe_realloc`.
They behave as corresponding standard functions but produce fatal error if
allocation fails. This change replaces the standard functions like 'malloc'
in the cases when the result of the allocation function is not checked
for null pointer.
Finally, there are plain C code, that uses malloc and similar functions. If
the result is not checked, assert statement is added.
Differential Revision: https://reviews.llvm.org/D43010
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325551 91177308-0d34-0410-b5e6-96231b3b80d8
Analysis of fails in the case of out of memory errors can be tricky on
Windows. Such error emerges at the point where memory allocation function
fails, but manifests itself when null pointer is used. These two points
may be distant from each other. Besides, next runs may not exhibit
allocation error.
Usual programming practice does not require checking result of 'operator
new' because it throws 'std::bad_alloc' in the case of allocation error.
However, LLVM is usually built with exceptions turned off, so 'new' can
return null pointer. This change installs custom new handler, which causes
fatal error in the case of out of memory. The handler is installed
automatically prior to call to 'main' during construction of a static
object defined in 'lib/Support/ErrorHandling.cpp'. If the application does
not use this file, the handler may be installed manually by a call to
'llvm::install_out_of_memory_new_handler', declared in
'include/llvm/Support/ErrorHandling.h".
There are calls to C allocation functions, malloc, calloc and realloc.
They are used for interoperability with C code, when allocated object has
variable size and when it is necessary to avoid call of constructors. In
many calls the result is not checked against null pointer. To simplify
checks, new functions are defined in the namespace 'llvm' with the
same names as these C function. These functions produce fatal error if
allocation fails. User should use 'llvm::malloc' instead of 'std::malloc'
in order to use the safe variant. This change replaces 'std::malloc'
in the cases when the result of allocation function is not checked against
null pointer.
Finally, there are plain C code, that uses malloc and similar functions. If
the result is not checked, assert statements are added.
Differential Revision: https://reviews.llvm.org/D43010
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325224 91177308-0d34-0410-b5e6-96231b3b80d8
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304787 91177308-0d34-0410-b5e6-96231b3b80d8
On FreeBSD backtrace is not part of libc and depends on libexecinfo
being available. Instead of using manual checks we can use the builtin
CMake module FindBacktrace.cmake to detect availability of backtrace()
in a portable way.
Patch By: Alex Richardson
Differential Revision: https://reviews.llvm.org/D27143
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300062 91177308-0d34-0410-b5e6-96231b3b80d8
Several static functions from the signal API can be invoked
simultaneously; RemoveFileOnSignal for instance can be called indirectly
by multiple parallel loadModule() invocations, which might lead to
the assertion:
Assertion failed: (NumRegisteredSignals < array_lengthof(RegisteredSignalInfo) && "Out of space for signal handlers!"),
function RegisterHandler, file /llvm/lib/Support/Unix/Signals.inc, line 105.
RemoveFileOnSignal calls RegisterHandlers(), which isn't currently
mutex protected, leading to the behavior above. This potentially affect
a few other users of RegisterHandlers() too.
rdar://problem/30381224
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298871 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit 63165f6ae3bac1623be36d4b3ce63afa1d51a30a.
After making this change, I discovered that _Unwind_Backtrace is
unable to unwind past a signal handler after an assertion failure.
I filed a bug report about that issue in rdar://29866587 but even if
we get a fix soon, it will be awhile before it get released.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291207 91177308-0d34-0410-b5e6-96231b3b80d8
Darwin's backtrace() function does not work with sigaltstack (which was
enabled when available with r270395) — it does a sanity check to make
sure that the current frame pointer is within the expected stack area
(which it is not when using an alternate stack) and gives up otherwise.
The alternative of _Unwind_Backtrace seems to work fine on macOS, so use
that when backtrace() fails. Note that we then use backtrace_symbols_fd()
with the addresses from _Unwind_Backtrace, but I’ve tested that and it
also seems to work fine. rdar://problem/28646552
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286851 91177308-0d34-0410-b5e6-96231b3b80d8
This adds a copy of the demangler in libcxxabi.
The code also has no dependencies on anything else in LLVM. To enforce
that I added it as another library. That way a BUILD_SHARED_LIBS will
fail if anyone adds an use of StringRef for example.
The no llvm dependency combined with the fact that this has to build
on linux, OS X and Windows required a few changes to the code. In
particular:
No constexpr.
No alignas
On OS X at least this library has only one global symbol:
__ZN4llvm16itanium_demangleEPKcPcPmPi
My current plan is:
Commit something like this
Change lld to use it
Change lldb to use it as the fallback
Add a few #ifdefs so that exactly the same file can be used in
libcxxabi to export abi::__cxa_demangle.
Once the fast demangler in lldb can handle any names this
implementation can be replaced with it and we will have the one true
demangler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280732 91177308-0d34-0410-b5e6-96231b3b80d8
sufficient in some cases; increase to 64KB, which should be enough for anyone :)
Patch by github.com/bryant!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279599 91177308-0d34-0410-b5e6-96231b3b80d8
If the result of the find is only used to compare against end(), just
use is_contained instead.
No functionality change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278469 91177308-0d34-0410-b5e6-96231b3b80d8
looking for it along $PATH. This allows installs of LLVM tools outside of
$PATH to find the symbolizer and produce pretty backtraces if they crash.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272232 91177308-0d34-0410-b5e6-96231b3b80d8
the C standard library implementation in use.
This works around a glibc bug in the backtrace() function where it fails to
produce a backtrace on x86_64 if libgcc / libunwind is statically linked.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270276 91177308-0d34-0410-b5e6-96231b3b80d8
- glibc is dynamically linked, and
- libgcc_s is unavailable (for instance, another library is being used to
provide the compiler runtime or libgcc is statically linked), and
- the target is x86_64.
If we run backtrace() and it fails to find any stack frames, try using
_Unwind_Backtrace instead if available.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269992 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/lib/Support/Signals.cpp:66:13: warning: unused function 'printSymbolizedStackTrace' [-Wunused-function]
llvm/lib/Support/Signals.cpp:52:13: warning: function 'findModulesAndOffsets' has internal linkage but is not defined [-Wundefined-internal]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252418 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
llvm-symbolizer understands both PDBs and DWARF, so it is more likely to
succeed at symbolization. If llvm-symbolizer is unavailable, we will
fall back to dbghelp. This also makes our crash traces more similar
between Windows and Linux.
Reviewers: Bigcheese, zturner, chapuni
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12884
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252118 91177308-0d34-0410-b5e6-96231b3b80d8
While theoratically required in pre-C++11 to avoid re-allocation upon call,
C++11 guarantees that c_str() returns a pointer to the internal array so
pre-calling c_str() is no longer required.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242983 91177308-0d34-0410-b5e6-96231b3b80d8
And expose it in Signals.h, allowing clients to call it directly,
possibly LLVMErrorHandler which currently calls RunInterruptHandlers
but not RunSignalHandlers, thus for example not printing the stack
backtrace on Unixish OSes. On Windows it does happen because
RunInterruptHandlers ends up calling the callbacks as well via
Cleanup(). This difference in behaviour and code structures in
*/Signals.inc should be patched in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242936 91177308-0d34-0410-b5e6-96231b3b80d8
Move CallBacksToRun into the common Signals.cpp, create RunCallBacksToRun()
and use these in both Unix/Signals.inc and Windows/Signals.inc.
Lots of potential code to be merged here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242925 91177308-0d34-0410-b5e6-96231b3b80d8
