These new builtins support a mechanism for logging OS events, using a
printf-like format string to specify the layout of data in a buffer.
The _buffer_size version of the builtin can be used to determine the size
of the buffer to allocate to hold the data, and then __builtin_os_log_format
can write data into that buffer. This implements format checking to report
mismatches between the format string and the data arguments. Most of this
code was written by Chris Willmore.
Differential Revision: https://reviews.llvm.org/D25888
llvm-svn: 284990
This checker does not emit reports, however it influences the analysis
by providing complete summaries for, or otherwise improving modeling of,
various standard library functions.
This should reduce the number of infeasible paths explored during analysis.
The custom function summary format used in this checker is superior to
body farms by causing less unnecessary state splits,
which would result in better analysis performance.
Differential Revision: https://reviews.llvm.org/D20811
llvm-svn: 284960
Summary: With MSVC 2013 and GCC < 4.8 gone, we can use the "constexpr" keyword.
Reviewers: bkramer, mehdi_amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25901
llvm-svn: 284947
mismatched dynamic exception specifications in expressions from an error to a
warning, since this is no longer ill-formed in C++1z.
Allow reference binding of a reference-to-non-noexcept function to a noexcept
function lvalue. As defect resolutions, also allow a conditional between
noexcept and non-noexcept function lvalues to produce a non-noexcept function
lvalue (rather than decaying to a function pointer), and allow function
template argument deduction to deduce a reference to non-noexcept function when
binding to a noexcept function type.
llvm-svn: 284905
This has two significant effects:
1) Direct relational comparisons between null pointer constants (0 and nullopt)
and pointers are now ill-formed. This was always the case for C, and it
appears that C++ only ever permitted by accident. For instance, cases like
nullptr < &a
are now rejected.
2) Comparisons and conditional operators between differently-cv-qualified
pointer types now work, and produce a composite type that both source
pointer types can convert to (when possible). For instance, comparison
between 'int **' and 'const int **' is now valid, and uses an intermediate
type of 'const int *const *'.
Clang previously supported #2 as an extension.
We do not accept the cases in #1 as an extension. I've tested a fair amount of
code to check that this doesn't break it, but if it turns out that someone is
relying on this, we can easily add it back as an extension.
This is a re-commit of r284800.
llvm-svn: 284890
Summary:
SetVector already used DenseSet, but SmallSetVector used std::set. This
leads to surprising performance differences. Moreover, it means that
the set of key types accepted by SetVector and SmallSetVector are
quite different!
In order to make this change, we had to convert some callsites that used
SmallSetVector<std::string, N> to use SmallSetVector<CachedHashString, N>
instead.
Reviewers: timshen
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25648
llvm-svn: 284887
Summary:
clang-tidy's modernize-use-auto check uses the SourceRange of a
TypeLoc when replacing the type with auto.
This was producing the wrong result for multi-token builtin types
like long long:
-long long *ll = new long long();
+auto long *ll = new long long();
Reviewers: alexfh, hokein, rsmith, Prazek, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25363
llvm-svn: 284885
This has two significant effects:
1) Direct relational comparisons between null pointer constants (0 and nullopt)
and pointers are now ill-formed. This was always the case for C, and it
appears that C++ only ever permitted by accident. For instance, cases like
nullptr < &a
are now rejected.
2) Comparisons and conditional operators between differently-cv-qualified
pointer types now work, and produce a composite type that both source
pointer types can convert to (when possible). For instance, comparison
between 'int **' and 'const int **' is now valid, and uses an intermediate
type of 'const int *const *'.
Clang previously supported #2 as an extension.
We do not accept the cases in #1 as an extension. I've tested a fair amount of
code to check that this doesn't break it, but if it turns out that someone is
relying on this, we can easily add it back as an extension.
llvm-svn: 284800
Recent versions of ld64 run a deduplicate pass, which is on by default.
Disable the pass by using -no_deduplicate in certain condition and
enhance total compile time.
rdar://problem/25455336
llvm-svn: 284798
The 'no_undeclared_includes' attribute should be used in a module to
tell that only non-modular headers and headers from used modules are
accepted.
The main motivation behind this is to prevent dep cycles between system
libraries (such as darwin) and libc++.
Patch by Richard Smith!
llvm-svn: 284797
Original commit message:
[c++1z] Teach composite pointer type computation how to compute the composite
pointer type of two function pointers with different noexcept specifications.
While I'm here, also teach it how to merge dynamic exception specifications.
llvm-svn: 284785
Code cleanup: address FIXME in the file
include/clang/Basic/FileManager.h and remove
copy-constructor of the class FileEntry.
Test plan: make check-clang
Differential revision: https://reviews.llvm.org/D22712
llvm-svn: 284782
pointer type of two function pointers with different noexcept specifications.
While I'm here, also teach it how to merge dynamic exception specifications.
llvm-svn: 284753
corresponding arguments are unexpanded pack expansions, we can compute the
result without substituting them. This significantly improves the memory usage
and performance of make_integer_sequence implementations that do this kind of
thing:
using result = integer_sequence<T, Ns ..., sizeof...(Ns) + Ns ...>;
... but note that such an implementation will still perform O(sizeof...(Ns)^2)
work while building the second pack expansion (we just have a somewhat lower
constant now).
In principle we could get this down to linear time by caching whether the
number of expansions of a pack is constant, or checking whether we're within an
alias template before scanning the pack for pack expansions (since that's the
only case in which we do substitutions within a dependent context at the
moment), but this patch doesn't attempt that.
llvm-svn: 284653
Summary:
Previously, when you did something not allowed in a host+device function
and then caused it to be codegen'ed, we would print out an error telling
you that you did something bad, but we wouldn't tell you how we decided
that the function needed to be codegen'ed.
This change causes us to print out a callstack when emitting deferred
errors. This is immensely helpful when debugging highly-templated code,
where it's often unclear how a function became known-emitted.
We only print the callstack once per function, after we print the all
deferred errors.
This patch also switches all of our hashtables to using canonical
FunctionDecls instead of regular FunctionDecls. This prevents a number
of bugs, some of which are caught by tests added here, in which we
assume that two FDs for the same function have the same pointer value.
Reviewers: rnk
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D25704
llvm-svn: 284647
Summary:
CanonicalDeclPtr<T> is just like a T*, except it calls
T::getCanonicalDecl() on construction.
This is useful as the key in a "set of canonical Decls" -- it's much
less error-prone than calling getCanonicalDecl() every time you touch
the set.
Reviewers: rnk
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D25703
llvm-svn: 284644
Summary:
This fixes two related bugs:
1) Previously, if you had a non-wrong side call at some source code
location L, we wouldn't emit errors for wrong-side calls that appeared
at L.
2) We'd only emit one wrong-side error per source code location, when we
actually want to emit it twice if we hit this line more than once due to
e.g. template instantiation.
Reviewers: tra
Subscribers: rnk, cfe-commits
Differential Revision: https://reviews.llvm.org/D25702
llvm-svn: 284643
This patch teaches clang to range check immediates for MIPS MSA instrinsics.
This checking is done strictly in comparison to some existing GCC
implementations. E.g. msa_andvi_b(var, 257) does not result in andvi $wX, 1.
Similarily msa_ldi_b takes a range of -128 to 127.
As part of this effort, correct the existing MSA test as it has both illegal
types and immediates.
Reviewers: vkalintiris
Differential Revision: https://reviews.llvm.org/D25017
llvm-svn: 284620
Gcc prints error if elements of left and right parts of a shift have different
sizes. This patch is provided the GCC compatibility.
Patch by Vladimir Yakovlev.
Differential Revision: https://reviews.llvm.org/D24669
llvm-svn: 284579
When dealing with objects that represent numbers, such as Objective-C NSNumber,
the language provides little protection from accidentally interpreting
the value of a pointer to such object as the value of the number represented
by the object. Results of such mis-interpretation may be unexpected.
The checker attempts to fill this gap in cases when the code is obviously
incorrect.
With "Pedantic" option enabled, this checker enforces a coding style to
completely prevent errors of this kind (off by default).
Differential Revision: https://reviews.llvm.org/D22968
llvm-svn: 284473
This commit changes code completion results for Objective-C block properties:
clang now suggests an additional completion result that displays the block
property together with '=' and the block literal placeholder for the appropriate
readwrite block properties.
This commit uses a simple heuristic to determine when it's appropriate to
suggest a setter completion for block properties: the additional block setter
completion is provided iff the member access that's being completed is a
standalone statement.
rdar://28481726
Differential Revision: https://reviews.llvm.org/D25520
llvm-svn: 284472
dependent noexcept specifications result in the same canonical function type.
We still use non-canonical hashing when deduplicating type sugar so that
diagnostics will point to the right place.
llvm-svn: 284457
This reverts commit r284176. It still marks some modules as invisible
that should be visible. Will follow up with the author with a test case.
llvm-svn: 284382
1) Merge and demote variable definitions when we find a redefinition in
MergeVarDecls, not only when we find one in AddInitializerToDecl (we only reach
the second case if it's the addition of the initializer itself that converts an
existing declaration into a definition).
2) When rebuilding a redeclaration chain for a variable, if we merge two
definitions together, mark the definitions as merged so the retained definition
is made visible whenever the demoted definition would have been.
Original commit message (from r283882):
[modules] PR28752: Do not instantiate variable declarations which are not visible.
Original patch by Vassil Vassilev! Changes listed above are mine.
llvm-svn: 284284
This commit combines a couple of redundant functions that do availability
attribute context checking into a more correct/simpler one.
Differential revision: https://reviews.llvm.org/D25283
llvm-svn: 284265
Summary: We need `__stosb` to be an intrinsic, because SecureZeroMemory function uses it without including intrin.h. Implementing it as a volatile memset is not consistent with MSDN specification, but it gives us target-independent IR while keeping the most important properties of `__stosb`.
Reviewers: rnk, hans, thakis, majnemer
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25334
llvm-svn: 284253
Summary:
If there are multiple <File, Replacements> pairs with the same file
path after removing dots, we only keep one pair (with path after dots being
removed) and discard the rest.
Reviewers: djasper
Subscribers: klimek, hokein, bkramer, cfe-commits
Differential Revision: https://reviews.llvm.org/D25565
llvm-svn: 284219
compiles without -fmodules-local-submodule-visibility. Original commit message:
[modules] When merging one definition into another, propagate the list of
re-exporting modules from the discarded definition to the retained definition.
llvm-svn: 284176
Summary: Previously global 64-bit versions of _Interlocked functions broke buildbots on i386, so now I'm adding them as builtins for x86-64 and ARM only (should they be also on AArch64? I had problems with testing it for AArch64, so I left it)
Reviewers: hans, majnemer, mstorsjo, rnk
Subscribers: cfe-commits, aemerson
Differential Revision: https://reviews.llvm.org/D25576
llvm-svn: 284172
Summary:
Emitting deferred diagnostics during codegen was a hack. It did work,
but usability was poor, both for us as compiler devs and for users. We
don't codegen if there are any sema errors, so for users this meant that
they wouldn't see deferred errors if there were any non-deferred errors.
For devs, this meant that we had to carefully split up our tests so that
when we tested deferred errors, we didn't emit any non-deferred errors.
This change moves checking for deferred errors into Sema. See the big
comment in SemaCUDA.cpp for an overview of the idea.
This checking adds overhead to compilation, because we have to maintain
a partial call graph. As a result, this change makes deferred errors a
CUDA-only concept (whereas before they were a general concept). If
anyone else wants to use this framework for something other than CUDA,
we can generalize at that time.
This patch makes the minimal set of test changes -- after this lands,
I'll go back through and do a cleanup of the tests that we no longer
have to split up.
Reviewers: rnk
Subscribers: cfe-commits, rsmith, tra
Differential Revision: https://reviews.llvm.org/D25541
llvm-svn: 284158
Summary:
Together these let you easily create diagnostics that
- are never emitted for host code
- are always emitted for __device__ and __global__ functions, and
- are emitted for __host__ __device__ functions iff these functions are
codegen'ed.
At the moment there are only three diagnostics that need this treatment,
but I have more to add, and it's not sustainable to write code for emitting
every such diagnostic twice, and from a special wrapper in SemaCUDA.cpp.
While we're at it, don't emit the function name in
err_cuda_device_exceptions: It's not necessary to print it, and making
this work in the new framework in the face of a null value for
dyn_cast<FunctionDecl>(CurContext) isn't worth the effort.
Reviewers: rnk
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D25139
llvm-svn: 284143
Summary: _BitScan intrinsics (and some others, for example _Interlocked and _bittest) are supposed to work on both ARM and x86. This is an attempt to isolate them, avoiding repeating their code or writing separate function for each builtin.
Reviewers: hans, thakis, rnk, majnemer
Subscribers: RKSimon, cfe-commits, aemerson
Differential Revision: https://reviews.llvm.org/D25264
llvm-svn: 284060
CodeCompletionResult's Declaration field is a const pointer to the
NamedDecl, and thus the constructor should take a const pointer as well.
llvm-svn: 284019
Original message:
"[modules] PR28752: Do not instantiate variable declarations which are not visible.
https://reviews.llvm.org/D24508
Patch developed in collaboration with Richard Smith!"
llvm-svn: 284008
This commit marks the transparent_union attributes as C only because clang
doesn't support them in C++ mode. Prior to this commit, clang still tried to
verify these attributes in C++, leading to crashes when analyzing templated
transparent_union unions that have dependent field types. This commit ensures
that such crashes won't happen again.
As a result of this commit clang now displays a warning every time it encounters
a transparent_union attribute in C++ mode.
Differential Revision: https://reviews.llvm.org/D25308
llvm-svn: 283995
This reverts commit r283802. It introduces temporarily static
initializers, because StringRef ctor isn't (yet) constexpr for
string literals.
I plan to get there this week, but apparently GCC is so terrible
with these static initializer right now (10 min+ extra codegen
time was reported) that I'll hold on to this patch till the
constexpr one is ready, and land these at the same time.
llvm-svn: 283920
Reapply r283827 by fixing the tests to not be target specific
Currently, driver level warnings do not show option names (e.g. warning:
complain about foo [-Woption-name]) in a diagnostic unless
-fdiagnostics-show-option is explictly specified. OTOH, the driver by
default turn this option on for CC1. Change the logic to show option
names by default in the driver as well.
Differential Revision: https://reviews.llvm.org/D24516
rdar://problem/27300909
llvm-svn: 283913
The backend now has the capability to save information from optimizations, the
same information that can be used to generate optimization diagnostics but in
machine-consumable form, into an output file. This can be enabled when using
opt (see r282539), and this change enables it when using clang. The idea is
that other tools will be able to consume these files, and perhaps in
combination with the original source code, produce various kinds of
optimization reports for users (and for compiler developers).
We now have at-least two tools that can consume these files:
* tools/llvm-opt-report
* utils/opt-viewer
Using the flag -fsave-optimization-record will cause the YAML file to be
generated; the file name will be based on the output file name (if we're using
-c or -S and have an output name), or the input file name. When we're using
CUDA, or some other offloading mechanism, separate files are generated for each
backend target. The output file name can be specified by the user using
-foptimization-record-file=filename.
Differential Revision: https://reviews.llvm.org/D25225
llvm-svn: 283834
match other CUDA preference orders, per discussion with jlebar. We now model
this in an attempt to match overload resolution as closely as possible:
- First, we throw out all non-callable (due to CUDA host/device mismatch)
operator delete functions.
- Then we apply sizedness / alignedness preferences based on whether the type
is overaligned and whether the deallocation function is a member.
- Finally, we use the CUDA callability preference as a tiebreaker.
llvm-svn: 283830
Currently, driver level warnings do not show option names (e.g. warning:
complain about foo [-Woption-name]) in a diagnostic unless
-fdiagnostics-show-option is explictly specified. OTOH, the driver by
default turn this option on for CC1. Change the logic to show option
names by default in the driver as well.
Differential Revision: https://reviews.llvm.org/D24516
rdar://problem/27300909
llvm-svn: 283827
The -gmodules option is all about putting debug type info into clang
modules and for line tables the type information is irrelevant, so
combining these two options makes no sense.
This commmit fixes the behavior to match the one documented on the
clang man page: the last -g... option wins.
<rdar://problem/27059770>
llvm-svn: 283810
Summary: It doesn't need to be refcounted anymore, either.
Reviewers: timshen
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25420
llvm-svn: 283768
Summary:
This is possible now that MapVector supports move-only values.
Depends on D25404.
Reviewers: timshen
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25405
llvm-svn: 283766
Make the -print-libgcc-file-name option print an appropriate compiler
runtime library, that is libgcc.a if gcc runtime is used
and an appropriate compiler-rt library if that runtime is used.
The main use for this is to allow linking executables built with
-nodefaultlibs (e.g. to avoid linking to the standard C++ library) to
the compiler runtime library, e.g. using:
clang++ ... -nodefaultlibs $(clang++ ... -print-libgcc-file-name)
in which case currently a program built like this linked to the gcc
runtime unconditionally. The patch fixes it to use compiler-rt libraries
instead when compiler-rt is the active runtime.
Differential Revision: https://reviews.llvm.org/D25338
llvm-svn: 283746
Summary:
These cause us to consider all functions in-between to be __host__
__device__.
You can nest these pragmas; you just can't have more 'end's than
'begin's.
Reviewers: rsmith
Subscribers: tra, jhen, cfe-commits
Differential Revision: https://reviews.llvm.org/D24975
llvm-svn: 283677
Summary:
Move CheckCUDACall from ActOnCallExpr and BuildDeclRefExpr to
DiagnoseUseOfDecl. This lets us catch some edge cases we were missing,
specifically around class operators.
This necessitates a few other changes:
- Avoid emitting duplicate deferred diags in CheckCUDACall.
Previously we'd carefully placed our call to CheckCUDACall such that
it would only ever run once for a particular callsite. But now this
isn't the case.
- Emit deferred diagnostics from a template
specialization/instantiation's primary template, in addition to from
the specialization/instantiation itself. DiagnoseUseOfDecl ends up
putting the deferred diagnostics on the template, rather than the
specialization, so we need to check both.
Reviewers: rsmith
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D24573
llvm-svn: 283637
Revert the -print-libgcc-file-name change as the new test fails
on Darwin. It needs to be updated to run the libgcc part only on systems
supporting that rtlib.
llvm-svn: 283586
The problem that caused the msvc crash has been indentified and fixed
in the previous commit. This patch contains the rest of r283092.
llvm-svn: 283584
This is the primary suspect for causing the msvc crash, now that vector of
smart pointers was proven to be safe. Probably the default {}-initializer
is the problem.
llvm-svn: 283573
Make the -print-libgcc-file-name option print an appropriate compiler
runtime library, that is libgcc.a if gcc runtime is used
and an appropriate compiler-rt library if that runtime is used.
The main use for this is to allow linking executables built with
-nodefaultlibs (e.g. to avoid linking to the standard C++ library) to
the compiler runtime library, e.g. using:
clang++ ... -nodefaultlibs $(clang++ ... -print-libgcc-file-name)
in which case currently a program built like this linked to the gcc
runtime unconditionally. The patch fixes it to use compiler-rt libraries
instead when compiler-rt is the active runtime.
Differential Revision: https://reviews.llvm.org/D25338
llvm-svn: 283572
Define the list of pieces in BugReport class. This is half of the changes
in the BugReport class code, which is pointed to by the msvc crash message.
llvm-svn: 283568
Define PathDiagnosticNotePiece. The next commit would be able to address the
BugReport class code that is pointed to by the msvc crash message.
llvm-svn: 283566
Returns when calling an inline function should not be merged in the ExplodedGraph unless they are same.
Differential Revision: https://reviews.llvm.org/D25326
llvm-svn: 283554
CheckSingleAssignmentConstraints. These no longer produce ExprError() when they
have not emitted an error, and reliably inform the caller when they *have*
emitted an error.
This fixes some serious issues where we would fail to emit any diagnostic for
invalid code and then attempt to emit code for an invalid AST, and conversely
some issues where we would emit two diagnostics for the same problem.
llvm-svn: 283508
Currently if the path diagnostic consumer (e.g HTMLDiagnostics and PlistDiagnostics) do not support cross file diagnostics then the path diagnostic report is silently omitted in the case of cross file diagnostics. The patch adds a little verbosity to Clang in this case.
The patch also adds help entry for the "--analyzer-output" driver option.
llvm-svn: 283499
the resulting specialization is not referenced by the rest of the AST. This
both avoids performing unnecessary reinstantiations in downstream users of the
AST file and fixes a bug (breaking modules self-host right now) where we would
sometimes fail to emit a definition of a class template specialization if we
imported just a declaration of it from elsewhere (see new testcase for reduced
example).
llvm-svn: 283489
new expression, distinguish between the case of a constant and non-constant
initializer. In the former case, if the bound is erroneous (too many
initializer elements, bound is negative, or allocated size overflows), reject,
and take the bound into account when determining whether we need to
default-construct any elements. In the remanining cases, move the logic to
check for default-constructibility of trailing elements into the initialization
code rather than inventing a bogus array bound, to cope with cases where the
number of initialized elements is not the same as the number of initializer
list elements (this can happen due to string literal initialization or brace
elision).
This also fixes rejects-valid and crash-on-valid errors when initializing a
new'd array of character type from a braced string literal.
llvm-svn: 283406
In the analyzer's path-sensitive reports, when a report goes through a branch
and the branch condition cannot be decided to be definitely true or false
(based on the previous execution path), an event piece is added that tells the
user that a new assumption is added upon the symbolic value of the branch
condition. For example, "Assuming 'a' is equal to 3".
The text of the assumption is hand-crafted in various manners depending on
the AST expression. If the AST expression is too complex and the text of
the assumption fails to be constructed, the event piece is omitted.
This causes loss of information and misunderstanding of the report.
Do not omit the event piece even if the expression is too complex;
add a piece with a generic text instead.
Differential Revision: https://reviews.llvm.org/D23300
llvm-svn: 283301
Summary:
This will let us (in a separate patch) allocate deferred diagnostics in
the ASTContext's PartialDiagnostic arena.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25260
llvm-svn: 283271
Summary: We need x86-64-specific builtins if we want to implement some of the MS intrinsics - winnt.h contains definitions of some functions for i386, but not for x86-64 (for example _InterlockedOr64), which means that we cannot treat them as builtins for both i386 and x86-64, because then we have definitions of builtin functions in winnt.h on i386.
Reviewers: thakis, majnemer, hans, rnk
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24598
llvm-svn: 283264
We could hook up /GL as an alias for -flto, but that might be
confusing, as clang-cl in that mode would not be drop-in compatible
with cl.exe /GL, as it requires the linker to be lld.
Exposing -flto seems like a less confusing way to expose this
functionality.
llvm-svn: 283255
Previously if a file-level function was defined inside befriending
template class, it always was treated as defined. For instance, the code like:
```
int func(int x);
template<typename T> class C1 {
friend int func(int x) { return x; }
};
template<typename T> class C2 {
friend int func(int x) { return x; }
};
```
could not be compiled due to function redefinition, although not of the templates
is instantiated. Moreover, the body of friend function can contain use of template
parameters, attempt to get definition of such function outside any instantiation
causes compiler abnormal termination.
Other compilers (gcc, icc) follow viewpoint that the body of the function defined
in friend declaration becomes available when corresponding class is instantiated.
This patch implements this viewpoint in clang.
Definitions introduced by friend declarations in template classes are not added
to the redeclaration chain of corresponding function. Only when the template is
instantiated, instantiation of the function definition is placed to the chain.
The fix was made in collaboration with Richard Smith.
This change fixes PR8035, PR17923, PR22307 and PR25848.
Differential Revision: http://reviews.llvm.org/D16989
llvm-svn: 283207
Summary:
With this commit simple coroutines can be created in plain C using coroutine builtins.
Reviewers: rnk, EricWF, rsmith
Subscribers: modocache, mgorny, mehdi_amini, beanz, cfe-commits
Differential Revision: https://reviews.llvm.org/D24373
llvm-svn: 283155
Highlight code clones referenced by the warning message with the help of
the extra notes feature recently introduced in r283092.
Change warning text to more clang-ish. Remove suggestions from the copy-paste
error checker diagnostics, because currently our suggestions are strictly 50%
wrong (we do not know which of the two code clones contains the error), and
for that reason we should not sound as if we're actually suggesting this.
Hopefully a better solution would bring them back.
Make sure the suspicious clone pair structure always mentions
the correct variable for the second clone.
Differential Revision: https://reviews.llvm.org/D24916
llvm-svn: 283094
These diagnostics are separate from the path-sensitive engine's path notes,
and can be added manually on top of path-sensitive or path-insensitive reports.
The new note diagnostics would appear as note:-diagnostic on console and
as blue bubbles in scan-build. In plist files they currently do not appear,
because format needs to be discussed with plist file users.
The analyzer option "-analyzer-config notes-as-events=true" would convert
notes to normal path notes, and put them at the beginning of the path.
This is a temporary hack to show the new notes in plist files.
A few checkers would be updated in subsequent commits,
including tests for this new feature.
Differential Revision: https://reviews.llvm.org/D24278
llvm-svn: 283092
Summary:
Also makes -fcoroutines_ts to be both a Driver and CC1 flag.
Patch mostly by EricWF.
Reviewers: rnk, cfe-commits, rsmith, EricWF
Subscribers: mehdi_amini
Differential Revision: https://reviews.llvm.org/D25130
llvm-svn: 283064
With templated classes, is possible to not be able to determine is a member
function is a special member function before the class is instantiated. Only
these special member functions can be defaulted. In some cases, knowing
whether a function is a special member function can't be determined until
instantiation, so an uninstantiated function could possibly be defaulted too.
Add a case to the error diagnostic when the function marked with a default is
not known to be a special member function.
llvm-svn: 282989
Also add a test that we disallow
__constant__ __shared__ int x;
because it's possible to break this without breaking
__shared__ __constant__ int x;
Reviewers: rnk
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D25125
llvm-svn: 282985
assume that ::operator new provides no more alignment than is necessary for any
primitive type, except when we're on a GNU OS, where glibc's malloc guarantees
to provide 64-bit alignment on 32-bit systems and 128-bit alignment on 64-bit
systems. This can be controlled by the command-line -fnew-alignment flag.
llvm-svn: 282974
Summary: The title says it all.
Reviewers: rsmith, GorNishanov
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D25078
llvm-svn: 282973
Summary:
This is probably the sane place for the attribute to go, but nvcc
specifically rejects it. Other GNU-style attributes are allowed in this
position (although judging from the warning it emits for
host/device/global, those attributes are applied to the lambda's
anonymous struct, not to the function itself).
It would be nice to have a FixIt message here, but doing so, or even
just getting the correct range for the attribute, including its '((' and
'))'s, is apparently Hard.
Reviewers: rnk
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D25115
llvm-svn: 282911
These are supposed to produce the same as normal volatile
pointer loads/stores. When -volatile:ms is specified,
normal volatile pointers are forced to have atomic semantics
(as is the default on x86 in MSVC mode). In that case,
these builtins should still produce non-atomic volatile
loads/stores without acquire/release semantics, which
the new test verifies.
These are only available on ARM (and on AArch64,
although clang doesn't support AArch64/Windows yet).
This implements what is missing for PR30394, making it possible
to compile C++ for ARM in MSVC mode with MSVC headers.
Differential Revision: https://reviews.llvm.org/D24986
llvm-svn: 282900
Summary:
This patch proposes a new class to generate and record action dependences related with offloading. The builder provides three main functionalities:
- Add device dependences to host actions.
- Add host dependence to device actions.
- Register device top-level actions.
The constructor of the builder detect the programming models that should be supported, and generates a specialized builder for each. If a new programming model is to be added in the future, only a new specialized builder has to be implemented.
When the specialized builder is generated, it produces programming-model-specific diagnostics.
A CUDA specialized builder is proposed in the patch that mostly consists of the partition of the current `buildCudaAction` by the three different functionalities.
Reviewers: tra, echristo, ABataev, jlebar, hfinkel
Subscribers: Hahnfeld, whchung, guansong, jlebar, mehdi_amini, andreybokhanko, tcramer, mkuron, cfe-commits, arpith-jacob, carlo.bertolli, caomhin
Differential Revision: https://reviews.llvm.org/D18172
llvm-svn: 282865
function correctly when targeting MS ABIs (this appears to have never mattered
prior to this change).
Update test case to always cover both 32-bit and 64-bit Windows ABIs, since
they behave somewhat differently from each other here.
Update test case to also cover operators , && and ||, which it appears are also
affected by P0145R3 (they're not explicitly called out by the design document,
but this is the emergent behavior of the existing wording).
Original commit message:
P0145R3 (C++17 evaluation order tweaks): evaluate the right-hand side of
assignment and compound-assignment operators before the left-hand side. (Even
if it's an overloaded operator.)
This completes the implementation of P0145R3 + P0400R0 for all targets except
Windows, where the evaluation order guarantees for <<, >>, and ->* are
unimplementable as the ABI requires the function arguments are evaluated from
right to left (because parameter destructors are run from left to right in the
callee).
llvm-svn: 282619
Summary:
Now two replacements are considered order-independent if applying them in
either order produces the same result. These include (but not restricted
to) replacements that:
- don't overlap (being directly adjacent is fine) and
- are overlapping deletions.
- are insertions at the same offset and applying them in either order
has the same effect, i.e. X + Y = Y + X if one inserts text X and the
other inserts text Y.
Discussion about this design can be found in D24717
Reviewers: djasper, klimek
Subscribers: omtcyfz, cfe-commits
Differential Revision: https://reviews.llvm.org/D24800
llvm-svn: 282577
assignment and compound-assignment operators before the left-hand side. (Even
if it's an overloaded operator.)
This completes the implementation of P0145R3 + P0400R0 for all targets except
Windows, where the evaluation order guarantees for <<, >>, and ->* are
unimplementable as the ABI requires the function arguments are evaluated from
right to left (because parameter destructors are run from left to right in the
callee).
llvm-svn: 282556
This patch corresponds to review:
https://reviews.llvm.org/D24397
It adds the __POWER9_VECTOR__ macro and the -mpower9-vector option along with
a number of altivec.h functions (refer to the code review for a list).
llvm-svn: 282481
This option behaves in a similar spirit as -save-temps and writes
internal llvm statistics in json format to a file.
Differential Revision: https://reviews.llvm.org/D24820
llvm-svn: 282426
__attribute__((amdgpu_flat_work_group_size(<min>, <max>))) - request minimum and maximum flat work group size
__attribute__((amdgpu_waves_per_eu(<min>[, <max>]))) - request minimum and/or maximum waves per execution unit
Differential Revision: https://reviews.llvm.org/D24513
llvm-svn: 282371
Summary:
Currently, a linker option must be used to control the backend
parallelism of ThinLTO. The linker option varies depending on the
linker (e.g. gold vs ld64). Add a new clang option -flto-jobs=N
to control this.
I've added in the wiring to pass this to the gold plugin. I also
added in the logic to pass this down in the form I understand that
ld64 uses on MacOS, for the darwin target.
Reviewers: mehdi_amini, dexonsmith
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D24826
llvm-svn: 282291
Summary:
- If a replacement has offset UINT_MAX, length 0, and a replacement text
that is an #include directive, this will insert the #include into the
correct block in the \p Code.
- If a replacement has offset UINT_MAX, length 1, and a replacement text
that is the name of the header to be removed, the header will be removed
from \p Code if it exists.
Reviewers: djasper
Subscribers: cfe-commits, klimek
Differential Revision: https://reviews.llvm.org/D24829
llvm-svn: 282253
The backend can't encode all possible values of the argument and will fail isel. Checking in the frontend presents a friendlier experience to the user.
I started with builtins that can only take _MM_CUR_DIRECTION or _MM_NO_EXC. More builtins coming in the future.
llvm-svn: 282228
Summary: People might want to receive warnings about pragmas but not about intrinsics that are implemented in intrin.h.
Reviewers: thakis, hans
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24775
llvm-svn: 282108
The return types on the AVX512 __builtin_ia32_gather3XivXdi builtins are incorrect. The return type should match the type of the pass through vector.
Differential Revision: https://reviews.llvm.org/D24785
-This line, and those below, will be ignored--
M include/clang/Basic/BuiltinsX86.def
llvm-svn: 282082
This checker should find the calls to blocking functions (for example: sleep, getc, fgets,read,recv etc.) inside a critical section. When sleep(x) is called while a mutex is held, other threads cannot lock the same mutex. This might take some time, leading to bad performance or even deadlock.
Example:
mutex_t m;
void f() {
sleep(1000); // Error: sleep() while m is locked! [f() is called from foobar() while m is locked]
// do some work
}
void foobar() {
lock(m);
f();
unlock(m);
}
A patch by zdtorok (Zoltán Dániel Török)!
Differential Revision: https://reviews.llvm.org/D21506
llvm-svn: 282011
Summary:
Diff to r281457:
- added a test case `CalculateRangesOfInsertionAroundReplacement`.
Reviewers: djasper
Subscribers: cfe-commits, klimek
Differential Revision: https://reviews.llvm.org/D24606
llvm-svn: 281891
Summary:
No behavioral change intended. The change makes iterating the replacements set more intuitive in Replacements class implementation. Previously, insertion is ordered before an deletion/replacement with the same offset, which is counter-intuitive for implementation, especially for a followup patch to support adding insertions around replacements.
With the current ordering, we only need to make `applyAllReplacements` iterate the replacements set reversely when applying them so that deletion/replacement is still applied before insertion with the same offset.
Reviewers: klimek, djasper
Subscribers: klimek, cfe-commits
Differential Revision: https://reviews.llvm.org/D24663
llvm-svn: 281819
* Fix an egregious comma usage.
* Remove the `static` keyword in the example since the variables should have
external linkage.
* Use C++11 attributes in the example.
llvm-svn: 281712
Currently, the Clang version is computed as follows:
1. LLVM defines major, minor, and patch versions, all statically set. Today,
these are 4, 0, and 0, respectively.
2. The static version numbers are combined into PACKAGE_VERSION along with a
suffix, so the result today looks like "4.0.0svn".
3. Clang extracts CLANG_VERSION from PACKAGE_VERSION using a regexp. The regexp
allows the patch level to omitted, and drops any non-digit trailing values.
Today, this result looks like "4.0.0".
4. CLANG_VERSION is then split further into CLANG_VERSION_MAJOR and
CLANG_VERSION_MINOR. Today, these resolve to 4 and 0, respectively.
5. If CLANG_VERSION matches a regexp with three version components, then
CLANG_VERSION_PATCHLEVEL is extracted and the CLANG_HAS_VERSION_PATCHLEVEL
variable is set to 1. Today, these values are 0 and 1, respectively.
6. The CLANG_VERSION_* variables (and CLANG_HAS_VERSION_PATCHLEVEL) are
configured into [llvm/tools/clang/]include/clang/Basic/Version.inc
verbatim by CMake.
7. In [llvm/tools/clang/]include/clang/Basic/Version.h, macros are defined
conditionally, based on CLANG_HAS_VERSION_PATCHLEVEL, to compute
CLANG_VERSION_STRING as either a two- or three-level version number. Today,
this value is "4.0.0", because despite the patchlevel being 0, it was
matched by regexp and is thus "HAS"ed by the preprocessor. This string is
then used wherever Clang's "version" is needed [*].
[*] Including, notably, by compiler-rt, for computing its installation path.
This change collapses steps 2-5 by defaulting Clang to use LLVM's (non-string)
version components for the Clang version (see [*] for why not PACKAGE_VERSION),
and collapses steps 6 and 7 by simply writing CLANG_VERSION_STRING into
Version.inc. The Clang version today always uses the patchlevel form, so the
collapsed Version.inc does not have logic for a version without a patch level.
Historically speaking, this technique began with the VER file in r82085 (which
survives in the form of the regexp in #3). The major, minor, and patchlevel
versions were introduced by r106863 (which remains in #4-6). The VER file itself
was deleted in favor of the LLVM version number in r106914. On the LLVM side,
the individual LLVM_VERSION_MAJOR, LLVM_VERSION_MINOR, and PACKAGE_VERSION
weren't introduced for nearly two more years, until r150405.
llvm-svn: 281666
The ARM-specific C attributes (currently just interrupt) need to check
for both the big- and little-endian versions of the triples, so that
they are accepted for both big and little endian targets.
TargetWindows and TargetMicrosoftCXXABI also only use the little-endian
triples, but this is correct as windows is not supported on big-endian
ARM targets (and this is asserted in lib/Basic/Targets.cpp).
Differential Revision: https://reviews.llvm.org/D24245
llvm-svn: 281596
Assert text for getSingleDecl() is inaccurate. Appears to have been copy pasted
from getDeclGroup().
Patch by Ben Taylor!
Reviewers: alexfh
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24518
llvm-svn: 281525
Summary: This patch converts finite/__finite to builtin functions so that it will be inlined by compiler.
Reviewers: hfinkel, davidxl, efriedma
Subscribers: efriedma, llvm-commits
Differential Revision: https://reviews.llvm.org/D24483
llvm-svn: 281509
Summary:
Extend `tooling::Replacements::add()` to support adding order-independent replacements.
Two replacements are considered order-independent if one of the following conditions is true:
- They do not overlap. (This is already supported.)
- One replacement is insertion, and the other is a replacement with
length > 0, and the insertion is adjecent to but not contained in the
other replacement. In this case, the replacement should always change
the original code instead of the inserted text.
Reviewers: klimek, djasper
Subscribers: cfe-commits, klimek
Differential Revision: https://reviews.llvm.org/D24515
llvm-svn: 281457
This patch adds an entry for "-rtlib" in the output of `man clang` and `clang -help`.
Patch by Lei Zhang!
Differential Revision: https://reviews.llvm.org/D24069
llvm-svn: 281440
-Wdiv-by-zero may as well be an alias for -Wdivision-by-zero rather than a GCC-compatibility no-op.
-Wno-shadow should disable -Wshadow-ivar.
-Weffc++ may as well enable -Wnon-virtual-dtor like it does in GCC.
llvm-svn: 281412
This mostly behaves cl.exe's behavior, even though clang-cl is stricter in some
corner cases and more lenient in others (see the included test).
To make the uuid declared previously here diagnostic work correctly, tweak
stripTypeAttributesOffDeclSpec() to keep attributes in the right order.
https://reviews.llvm.org/D24469
llvm-svn: 281367
We also need to add ObjCTypeParamTypeLoc. ObjCTypeParamType supports the
representation of "T <protocol>" where T is a type parameter. Before this,
we use TypedefType to represent the type parameter for ObjC.
ObjCTypeParamType has "ObjCTypeParamDecl *OTPDecl" and it extends from
ObjCProtocolQualifiers. It is a non-canonical type and is canonicalized
to the underlying type with the protocol qualifiers.
rdar://24619481
rdar://25060179
Differential Revision: http://reviews.llvm.org/D23079
llvm-svn: 281355
To construct the canonical type of ObjCTypeParamType, we need to apply
qualifiers on ObjCObjectPointerType. The updated applyObjCProtocolQualifiers
handles this case by merging the protocol lists, constructing a new
ObjCObjectType, then a new ObjCObjectPointerType.
rdar://24619481
rdar://25060179
Differential Revision: http://reviews.llvm.org/D24059
llvm-svn: 281353
Now ObjCObjectType extends from ObjCProtocolQualifiers. We save number of
protocols in ObjCProtocolQualifiers.
This is in preparation of adding a new type class ObjCTypeParamType that
can take protocol qualifiers.
rdar://24619481
rdar://25060179
Differential Revision: http://reviews.llvm.org/D23078
llvm-svn: 281351
The unit tests in this patch demonstrate the need to traverse template
parameter lists of DeclaratorDecls (e.g. VarDecls, CXXMethodDecls) and
TagDecls (e.g. EnumDecls, RecordDecls).
Fixes PR29042.
https://reviews.llvm.org/D24268
Patch from Lukasz
Łukasz Anforowicz <lukasza@chromium.org>!
llvm-svn: 281345
Original commit message:
Add -fdiagnostics-show-hotness
Summary:
I've recently added the ability for optimization remarks to include the
hotness of the corresponding code region. This uses PGO and allows
filtering of the optimization remarks by relevance. The idea was first
discussed here:
http://thread.gmane.org/gmane.comp.compilers.llvm.devel/98334
The general goal is to produce a YAML file with the remarks. Then, an
external tool could dynamically filter these by hotness and perhaps by
other things.
That said it makes sense to also expose this at the more basic level
where we just include the hotness info with each optimization remark.
For example, in D22694, the clang flag was pretty useful to measure the
overhead of the additional analyses required to include hotness.
(Without the flag we don't even run the analyses.)
For the record, Hal has already expressed support for the idea of this
patch on IRC.
Differential Revision: https://reviews.llvm.org/D23284
llvm-svn: 281293
Summary:
I've recently added the ability for optimization remarks to include the
hotness of the corresponding code region. This uses PGO and allows
filtering of the optimization remarks by relevance. The idea was first
discussed here:
http://thread.gmane.org/gmane.comp.compilers.llvm.devel/98334
The general goal is to produce a YAML file with the remarks. Then, an
external tool could dynamically filter these by hotness and perhaps by
other things.
That said it makes sense to also expose this at the more basic level
where we just include the hotness info with each optimization remark.
For example, in D22694, the clang flag was pretty useful to measure the
overhead of the additional analyses required to include hotness.
(Without the flag we don't even run the analyses.)
For the record, Hal has already expressed support for the idea of this
patch on IRC.
Differential Revision: https://reviews.llvm.org/D23284
llvm-svn: 281276
remark flags. For now I'm checking in a copy of the built documentation, but we
can replace this with a placeholder (as we do for the attributes reference
documentation) once we enable building this server-side.
llvm-svn: 281192
Our limited debug info optimizations are breaking down at DLL
boundaries, so we're going to evaluate the size impact of these
settings, and possibly change the default.
Users should be able to override our settings, though.
llvm-svn: 281056
Avoided wrapping NullabilityDocs at 80cols, since that would've made
this diff much bigger, and never-ending lines seems to be the style for
many of the null-related docs.
llvm-svn: 281017
- Simplify signature of CreateVTableInitializer function.
- Move vtable component builder to a separate function.
- Remove unnecessary accessors from VTableLayout class.
This is in preparation for a future change that will alter the type of the
vtable initializer.
Differential Revision: https://reviews.llvm.org/D22642
llvm-svn: 280897
r280553 introduced an issue where we'd emit ambiguity errors for code
like:
```
void foo(int *, int);
void foo(unsigned int *, unsigned int);
void callFoo() {
unsigned int i;
foo(&i, 0); // ambiguous: int->unsigned int is worse than int->int,
// but unsigned int*->unsigned int* is better than
// int*->int*.
}
```
This patch fixes this issue by changing how we handle ill-formed (but
valid) implicit conversions. Candidates with said conversions now always
rank worse than candidates without them, and two candidates are
considered to be equally bad if they both have these conversions for
the same argument.
Additionally, this fixes a case in C++11 where we'd complain about an
ambiguity in a case like:
```
void f(char *, int);
void f(const char *, unsigned);
void g() { f("abc", 0); }
```
...Since conversion to char* from a string literal is considered
ill-formed in C++11 (and deprecated in C++03), but we accept it as an
extension.
llvm-svn: 280847
There is a bug causing pch to be validated even though -fno-validate-pch is set. This patch fixes it.
ASTReader relies on ASTReaderListener to initialize SuggestedPredefines, which is required for compilations using PCH. Before this change, PCHValidator is the default ASTReaderListener. After this change, when -fno-validate-pch is set, PCHValidator is disabled, but we need a replacement ASTReaderListener to initialize SuggestedPredefines. Class SimpleASTReaderListener is implemented for this purpose.
This change only affects -fno-validate-pch. There is no functional change if -fno-validate-pch is not set.
If -fno-validate-pch is not set, conflicts in predefined macros between pch and current compiler instance causes error.
If -fno-validate-pch is set, predefine macros in current compiler override those in pch so that compilation can continue.
Differential Revision: https://reviews.llvm.org/D24054
llvm-svn: 280842
Parse pragma intrinsic, display warning if the function isn't a builtin
function in clang and suggest including intrin.h.
Patch by Albert Gutowski!
Reviewers: aaron.ballman, rnk
Subscribers: aaron.ballman, cfe-commits
Differential Revision: https://reviews.llvm.org/D23944
llvm-svn: 280825
OpenCL requires __ENDIAN_LITTLE__ be set for little endian targets.
The default for targets was also apparently big endian, so AMDGPU
was incorrectly reported as big endian. Set this from the triple
so targets don't have another place to set the endianness.
llvm-svn: 280787
Some Windows SDK classes, for example
Windows::Storage::Streams::IBufferByteAccess, use the ATL way of spelling
attributes:
[uuid("....")] class IBufferByteAccess {};
To be able to use __uuidof() to grab the uuid off these types, clang needs to
support uuid as a Microsoft attribute. There was already code to skip Microsoft
attributes, extend that to look for uuid and parse it. Use the new "Microsoft"
attribute type added in r280575 (and r280574, r280576) for this.
Final part of https://reviews.llvm.org/D23895
llvm-svn: 280578
There was already a function that moved attributes off the declspec into
an attribute list for attributes applying to the type, teach that function to
also move Microsoft attributes around and rename it to match its new broader
role.
Nothing uses Microsoft attributes yet, so no behavior change.
Part of https://reviews.llvm.org/D23895
llvm-svn: 280576
This is for attributes in []-delimited lists preceding a class, like e.g.
`[uuid("...")] class Foo {};` Not used by anything yet, so no behavior change.
Part of https://reviews.llvm.org/D23895
llvm-svn: 280575
This patch allows us to perform incompatible pointer conversions when
resolving overloads in C. So, the following code will no longer fail to
compile (though it will still emit warnings, assuming the user hasn't
opted out of them):
```
void foo(char *) __attribute__((overloadable));
void foo(int) __attribute__((overloadable));
void callFoo() {
unsigned char bar[128];
foo(bar); // selects the char* overload.
}
```
These conversions are ranked below all others, so:
A. Any other viable conversion will win out
B. If we had another incompatible pointer conversion in the example
above (e.g. `void foo(int *)`), we would complain about
an ambiguity.
Differential Revision: https://reviews.llvm.org/D24113
llvm-svn: 280553
Summary:
This attribute specifies expectations about the initialization of static and
thread local variables. Specifically that the variable has a
[constant initializer](http://en.cppreference.com/w/cpp/language/constant_initialization)
according to the rules of [basic.start.static]. Failure to meet this expectation
will result in an error.
Static objects with constant initializers avoid hard-to-find bugs caused by
the indeterminate order of dynamic initialization. They can also be safely
used by other static constructors across translation units.
This attribute acts as a compile time assertion that the requirements
for constant initialization have been met. Since these requirements change
between dialects and have subtle pitfalls it's important to fail fast instead
of silently falling back on dynamic initialization.
```c++
// -std=c++14
#define SAFE_STATIC __attribute__((require_constant_initialization)) static
struct T {
constexpr T(int) {}
~T();
};
SAFE_STATIC T x = {42}; // OK.
SAFE_STATIC T y = 42; // error: variable does not have a constant initializer
// copy initialization is not a constant expression on a non-literal type.
```
This attribute can only be applied to objects with static or thread-local storage
duration.
Reviewers: majnemer, rsmith, aaron.ballman
Subscribers: jroelofs, cfe-commits
Differential Revision: https://reviews.llvm.org/D23385
llvm-svn: 280525
Summary:
This attribute specifies expectations about the initialization of static and
thread local variables. Specifically that the variable has a
[constant initializer](http://en.cppreference.com/w/cpp/language/constant_initialization)
according to the rules of [basic.start.static]. Failure to meet this expectation
will result in an error.
Static objects with constant initializers avoid hard-to-find bugs caused by
the indeterminate order of dynamic initialization. They can also be safely
used by other static constructors across translation units.
This attribute acts as a compile time assertion that the requirements
for constant initialization have been met. Since these requirements change
between dialects and have subtle pitfalls it's important to fail fast instead
of silently falling back on dynamic initialization.
```c++
// -std=c++14
#define SAFE_STATIC __attribute__((require_constant_initialization)) static
struct T {
constexpr T(int) {}
~T();
};
SAFE_STATIC T x = {42}; // OK.
SAFE_STATIC T y = 42; // error: variable does not have a constant initializer
// copy initialization is not a constant expression on a non-literal type.
```
This attribute can only be applied to objects with static or thread-local storage
duration.
Reviewers: majnemer, rsmith, aaron.ballman
Subscribers: jroelofs, cfe-commits
Differential Revision: https://reviews.llvm.org/D23385
llvm-svn: 280516