The original proposal was seen in Apr 2019 and we accidentally used
that date (201904L) as the feature testing value. However, WG14 N2408
was adopted at the Oct 2019 meeting and so that's the correct date for
the feature testing macro. The committee draft for C2x shows 201910L
for this value, so this changes brings us in line with the standard.
The original proposal was adopted in Apr 2019, but was subsequently
updated by WG14 N2662 in June 2021. We already supported the attribute
on a label and it behaved as expected, but we had not bumped the
feature test value.
The original proposal was adopted in Apr 2019 and so the previous value
was 201904L. However, a subsequent proposal (N2448) was adopted to add
an optional message argument to the attribute. We already support that
functionality, but had not bumped the feature test value.
This reverts commit d200db3863, which causes a
clang crash. See https://reviews.llvm.org/D111283#3785755
Test case for convenience:
```
template <typename T>
using P = int T::*;
template <typename T, typename... A>
void j(P<T>, T, A...);
template <typename T>
void j(P<T>, T);
struct S {
int b;
};
void g(P<S> k, S s) { j(k, s); }
```
Set the EmulatedTLS option based on `Triple::hasDefaultEmulatedTLS()`
if the user didn't specify it; set `ExplicitEmulatedTLS` to true
in `llvm::TargetOptions` and set `EmulatedTLS` to Clang's
opinion of what the default or preference is.
This avoids any risk of deviance between the two.
This affects one check of `getCodeGenOpts().EmulatedTLS` in
`shouldAssumeDSOLocal` in CodeGenModule, but as that check only
is done for `TT.isWindowsGNUEnvironment()`, and
`hasDefaultEmulatedTLS()` returns false for such environments
it doesn't make any current testable difference - thus NFC.
Some mingw distributions carry a downstream patch, that enables
emulated TLS by default for mingw targets in `hasDefaultEmulatedTLS()`
- and for such cases, this patch does make a difference and fixes the
detection of emulated TLS, if it is implicitly enabled.
Differential Revision: https://reviews.llvm.org/D132916
It turns out that in certain cases `SymbolRegions` are wrapped by
`ElementRegions`; in others, it's not. This discrepancy can cause the
analyzer not to recognize if the two regions are actually referring to
the same entity, which then can lead to unreachable paths discovered.
Consider this example:
```lang=C++
struct Node { int* ptr; };
void with_structs(Node* n1) {
Node c = *n1; // copy
Node* n2 = &c;
clang_analyzer_dump(*n1); // lazy...
clang_analyzer_dump(*n2); // lazy...
clang_analyzer_dump(n1->ptr); // rval(n1->ptr): reg_$2<int * SymRegion{reg_$0<struct Node * n1>}.ptr>
clang_analyzer_dump(n2->ptr); // rval(n2->ptr): reg_$1<int * Element{SymRegion{reg_$0<struct Node * n1>},0 S64b,struct Node}.ptr>
clang_analyzer_eval(n1->ptr != n2->ptr); // UNKNOWN, bad!
(void)(*n1);
(void)(*n2);
}
```
The copy of `n1` will insert a new binding to the store; but for doing
that it actually must create a `TypedValueRegion` which it could pass to
the `LazyCompoundVal`. Since the memregion in question is a
`SymbolicRegion` - which is untyped, it needs to first wrap it into an
`ElementRegion` basically implementing this untyped -> typed conversion
for the sake of passing it to the `LazyCompoundVal`.
So, this is why we have `Element{SymRegion{.}, 0,struct Node}` for `n1`.
The problem appears if the analyzer evaluates a read from the expression
`n1->ptr`. The same logic won't apply for `SymbolRegionValues`, since
they accept raw `SubRegions`, hence the `SymbolicRegion` won't be
wrapped into an `ElementRegion` in that case.
Later when we arrive at the equality comparison, we cannot prove that
they are equal.
For more details check the corresponding thread on discourse:
https://discourse.llvm.org/t/are-symbolicregions-really-untyped/64406
---
In this patch, I'm eagerly wrapping each `SymbolicRegion` by an
`ElementRegion`; basically canonicalizing to this form.
It seems reasonable to do so since any object can be thought of as a single
array of that object; so this should not make much of a difference.
The tests also underpin this assumption, as only a few were broken by
this change; and actually fixed a FIXME along the way.
About the second example, which does the same copy operation - but on
the heap - it will be fixed by the next patch.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D132142
Hidden visibility is incompatible with dllexport.
Hidden and protected visibilities are incompatible with dllimport.
(PlayStation uses dllexport protected.)
When an explicit visibility attribute applies on a dllexport/dllimport
declaration, report a Frontend error (Sema does not compute visibility).
Reviewed By: mstorsjo
Differential Revision: https://reviews.llvm.org/D133266
__declspec(safebuffers) is equivalent to
__attribute__((no_stack_protector)). This information is recorded in
CodeView.
While we are here, add support for strict_gs_check.
If the declaration of an identifier has block scope, and the identifier has
external or internal linkage, the declaration shall have no initializer for
the identifier.
Clang now gives a more suitable diagnosis for this case.
Fixes https://github.com/llvm/llvm-project/issues/57478
Signed-off-by: Jun Zhang <jun@junz.org>
Differential Revision: https://reviews.llvm.org/D133088
The diagnostics here are correct, but the note is really silly. It
talks about reinterpret_cast in C code. So rewording it for c mode by
using another %select{}.
```
int array[(long)(char *)0];
```
previous note:
```
cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
```
reworded note:
```
this conversion is not allowed in a constant expression
```
Differential Revision: https://reviews.llvm.org/D133194
HLSL doesn't have a runtime loader model that supports global
construction by a loader or runtime initializer. To allow us to leverage
global constructors with minimal code generation impact we put calls to
the global constructors inside the generated entry function.
Differential Revision: https://reviews.llvm.org/D132977
This option can be used to enable Control Flow Guard checks and
generation of address-taken function table. They are equivalent to
`/guard:cf` and `/guard:cf,nochecks` in clang-cl. Passing this flag to
the Clang driver will also pass `--guard-cf` to the MinGW linker.
This feature is disabled by default. The option `-mguard=none` is also
available to explicitly disable this feature.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D132810
LLVM contains a helpful function for getting the size of a C-style
array: `llvm::array_lengthof`. This is useful prior to C++17, but not as
helpful for C++17 or later: `std::size` already has support for C-style
arrays.
Change call sites to use `std::size` instead. Leave the few call sites that
use a locally defined `array_lengthof` that are meant to test previous bugs
with NTTPs in clang analyzer and SemaTemplate.
Differential Revision: https://reviews.llvm.org/D133520
This reverts commit 16e5d6d7f9.
There are multiple complaints on the review.
In addition, it may cause spurious
```
error: invalid operands to binary expression ('SinkPrinter' and 'char[cluster_name_length]')
note: candidate template ignored: substitution failure: variably modified type 'char *' cannot be used as a template argument SinkPrinter operator<<(const SinkPrinter &s, T) {
```
for some C++ code
This continues D111283 by extending the getCommonSugaredType
implementation to also merge non-canonical type nodes.
We merge these nodes by going up starting from the canonical
node, calculating their merged properties on the way.
If we reach a pair that is too different, or which we could not
otherwise unify, we bail out and don't try to keep going on to
the next pair, in effect striping out all the remaining top-level
sugar nodes. This avoids mismatching 'companion' nodes, such as
ElaboratedType, so that they don't end up elaborating some other
unrelated thing.
Depends on D111509
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D130308
After upgrading the type deduction machinery to retain type sugar in
D110216, we were left with a situation where there is no general
well behaved mechanism in Clang to unify the type sugar of multiple
deductions of the same type parameter.
So we ended up making an arbitrary choice: keep the sugar of the first
deduction, ignore subsequent ones.
In general, we already had this problem, but in a smaller scale.
The result of the conditional operator and many other binary ops
could benefit from such a mechanism.
This patch implements such a type sugar unification mechanism.
The basics:
This patch introduces a `getCommonSugaredType(QualType X, QualType Y)`
method to ASTContext which implements this functionality, and uses it
for unifying the results of type deduction and return type deduction.
This will return the most derived type sugar which occurs in both X and
Y.
Example:
Suppose we have these types:
```
using Animal = int;
using Cat = Animal;
using Dog = Animal;
using Tom = Cat;
using Spike = Dog;
using Tyke = Dog;
```
For `X = Tom, Y = Spike`, this will result in `Animal`.
For `X = Spike, Y = Tyke`, this will result in `Dog`.
How it works:
We take two types, X and Y, which we wish to unify as input.
These types must have the same (qualified or unqualified) canonical
type.
We dive down fast through top-level type sugar nodes, to the
underlying canonical node. If these canonical nodes differ, we
build a common one out of the two, unifying any sugar they had.
Note that this might involve a recursive call to unify any children
of those. We then return that canonical node, handling any qualifiers.
If they don't differ, we walk up the list of sugar type nodes we dived
through, finding the last identical pair, and returning that as the
result, again handling qualifiers.
Note that this patch will not unify sugar nodes if they are not
identical already. We will simply strip off top-level sugar nodes that
differ between X and Y. This sugar node unification will instead be
implemented in a subsequent patch.
This patch also implements a few users of this mechanism:
* Template argument deduction.
* Auto deduction, for functions returning auto / decltype(auto), with
special handling for initializer_list as well.
Further users will be implemented in a subsequent patch.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D111283
This reverts commit 91d8324366.
The combo dllexport protected makes sense and is used by PlayStation.
Will change the patch to allow dllexport protected.
Intend to use `ODRDiagsEmitter` during parsing to diagnose a parsed
definition differing from a definition with the same name from a hidden
[sub]module.
Differential Revision: https://reviews.llvm.org/D128695
Introduces the frontend flag -fexperimental-sanitize-metadata=, which
enables SanitizerBinaryMetadata instrumentation.
The first intended user of the binary metadata emitted will be a variant
of GWP-TSan [1]. The plan is to open source a stable and production
quality version of GWP-TSan. The development of which, however, requires
upstream compiler support.
[1] https://llvm.org/devmtg/2020-09/slides/Morehouse-GWP-Tsan.pdf
Until the tool has been open sourced, we mark this kind of
instrumentation as "experimental", and reserve the option to change
binary format, remove features, and similar.
Reviewed By: vitalybuka, MaskRay
Differential Revision: https://reviews.llvm.org/D130888
Directive `dependency_directives_scan::tokens_present_before_eof` is introduced to indicate there were tokens present before
the last scanned dependency directive and EOF.
This is useful to ensure we correctly identify the macro guards when lexing using the dependency directives.
Differential Revision: https://reviews.llvm.org/D133357
Per the documentation, these restrictions were intended to apply to textual headers but previously this didn't work because we decided there was no requesting module when the `#include` was in a textual header.
A `-cc1` flag is provided to restore the old behavior for transitionary purposes.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D132779
The backend now has a 32bit feature as part of the recent mtune
patch. We can now use that make our rv32-only builtin error checking
work the same way as rv64-only errors.
Reviewed By: kito-cheng
Differential Revision: https://reviews.llvm.org/D132192
This matches the behavior for all the other -fopenmp options,
as well as -frtlib-add-rpath.
For context, Fedora passes this flag by default in case OpenMP is
used, and this results in a warning if it (usually) isn't, which
causes build failures for some programs with unnecessarily strict
build systems (like Ruby).
Differential Revision: https://reviews.llvm.org/D133316
dllimport/dllexport is incompatible with protected/hidden visibilities.
(Arguably dllexport semantics is compatible with protected but let's reject the
combo for simplicity.)
When an explicit visibility attribute applies on a dllexport/dllimport
declaration, report a Frontend error (Sema does not compute visibility).
Reviewed By: mstorsjo
Differential Revision: https://reviews.llvm.org/D133266
Introduced by 23a5090c6, some style option markers indicated
'clang-format 4', though their respective options were available in
earlier releases.
Differential Revision: https://reviews.llvm.org/D129934
Previously we may call Sema::FindAllocationFunctions directly to lookup
allocation functions directly instead of using our wrapped lambda
LookupAllocationFunction, which is slightly incosnsistent. It will be
helpful to refactor this for further changes.
Also previously, when we lookup 'operator new(std::size_t, std::nothrow_t)' in
case we found `get_return_object_on_allocation_failure` in the
promise_type, the compiler will try to look at the allocation function
in promise_type. However, this is not wanted actually. According to
[dcl.fct.def.coroutine]p10:
> if a global allocation function is selected, the
> ::operator new(size_t, nothrow_t) form is used.
So we should only lookup for `::operator (size_t, nothrow_t)` for the
global allocation function. For the allocation function in the
promise_type, the requirement is that it shouldn't throw, which has
already been checked.
Given users generally include headers from standard libs so it will
generally include the <new> header, so this change should be a trivial
one and shouldn't affect almost any user.
This patch introduces a new checker, called NewArraySize checker,
which detects if the expression that yields the element count of
the array in new[], results in an Undefined value.
Differential Revision: https://reviews.llvm.org/D131299
They lead to -Wunused-command-line-argument and should be written as -Ttext=
instead, but the driver options end with a space. -Ttext=0 can be accepted by
the JoinedOrSeparate -T, so the JoinedOrSeparate -Ttext/etc are unneeded.
This change refactors the MuiltiplexExternalSemaSource to take ownership
of the underlying sources. As a result it makes a larger cleanup of
external source ownership in Sema and the ChainedIncludesSource.
Reviewed By: aaron.ballman, aprantl
Differential Revision: https://reviews.llvm.org/D133158
Someday we would like to support HLSL on a wider range of targets, but
today targeting anything other than `dxil` is likly to cause lots of
headaches. This adds an error and tests to validate that the expected
target is `dxil-?-shadermodel`.
We will continue to do a best effort to ensure the code we write makes
it easy to support other targets (like SPIR-V), but this error will
prevent users from hitting frustrating errors for unsupported cases.
Reviewed By: jcranmer-intel, Anastasia
Differential Revision: https://reviews.llvm.org/D132056
* If GCC is configured with `--disable-multi-arch`, `--print-multiarch` output is an empty line.
* If GCC is configured with `--enable-multi-arch`, `--print-multiarch` output may be a normalized triple or (on Debian, 'vendor' is omitted) `x86_64-linux-gnu`.
The Clang support D101400 just prints the Debian multiarch style triple
unconditionally, but the string is not really expected for non-Debian systems.
AIUI many Linux distributions and non-Linux OSes don't configure GCC with `--enable-multi-arch`.
Instead of getting us in the trouble of supporting all kinds of variants, drop the support as before D101400.
Close https://github.com/llvm/llvm-project/issues/51469
Reviewed By: phosek
Differential Revision: https://reviews.llvm.org/D133170
Aaron Ballman