This patch rewords the static assert diagnostic output. Failing a
_Static_assert in C should not report that static_assert failed. This
changes the wording to be more like GCC and uses "static assertion"
when possible instead of hard coding the name. This also changes some
instances of 'static_assert' to instead be based on the token in the
source code.
Differential Revision: https://reviews.llvm.org/D129048
Looks like we again are going to have problems with libcxx tests that
are overly specific in their dependency on clang's diagnostics.
This reverts commit 6542cb55a3.
This patch is basically the rewording of the static assert statement's
output(error) on screen after failing. Failing a _Static_assert in C
should not report that static_assert failed. It’d probably be better to
reword the diagnostic to be more like GCC and say “static assertion”
failed in both C and C++.
consider a c file having code
_Static_assert(0, "oh no!");
In clang the output is like:
<source>:1:1: error: static_assert failed: oh no!
_Static_assert(0, "oh no!");
^ ~
1 error generated.
Compiler returned: 1
Thus here the "static_assert" is not much good, it will be better to
reword it to the "static assertion failed" to more generic. as the gcc
prints as:
<source>:1:1: error: static assertion failed: "oh no!"
1 | _Static_assert(0, "oh no!");
| ^~~~~~~~~~~~~~
Compiler returned: 1
The above can also be seen here. This patch is about rewording
the static_assert to static assertion.
Differential Revision: https://reviews.llvm.org/D129048
This reverts commit b7e77ff25f.
Reason: Broke sanitizer builds bots + libcxx. 'static assertion
expression is not an integral constant expression'. More details
available in the Phabricator review: https://reviews.llvm.org/D129048
This patch rewords the static assert diagnostic output. Failing a
_Static_assert in C should not report that static_assert failed. This
changes the wording to be more like GCC and uses "static assertion"
when possible instead of hard coding the name. This also changes some
instances of 'static_assert' to instead be based on the token in the
source code.
Differential Revision: https://reviews.llvm.org/D129048
This patch allows the same implicit conversions for vector-scalar
operations in SVE that are allowed for NEON.
Depends on D126377
Reviewed By: c-rhodes
Differential Revision: https://reviews.llvm.org/D126380
This patch enables shift operators on SVE vector types, as well as
supporting vector-scalar shift operations.
Shifts by a scalar that is wider than the contained type in the
vector are permitted but as in the C standard if the value is larger
than the width of the type the behavior is undefined.
Differential Revision: https://reviews.llvm.org/D123303
Comparison operators on SVE types return a signed integer vector
of the same width as the incoming SVE type. This matches the existing
behaviour for NEON types.
Differential Revision: https://reviews.llvm.org/D122404
This patch implements support for the +, -, *, / and % operators on sizeless SVE
types. Support for these operators on svbool_t is excluded.
Differential Revision: https://reviews.llvm.org/D120323
This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.
As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith, #libc, ldionne
Differential Revision: https://reviews.llvm.org/D110216
This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.
As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D110216
This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.
As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D110216
(This relands 59337263ab and makes sure comma operator
diagnostics are suppressed in a SFINAE context.)
While at it, add the diagnosis message "left operand of comma operator has no effect" (used by GCC) for comma operator.
This also makes Clang diagnose in the constant evaluation context which aligns with GCC/MSVC behavior. (https://godbolt.org/z/7zxb8Tx96)
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D103938
While at it, add the diagnosis message "left operand of comma operator has no effect" (used by GCC) for comma operator.
This also makes Clang diagnose in the constant evaluation context which aligns with GCC/MSVC behavior. (https://godbolt.org/z/7zxb8Tx96)
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D103938
While at it, add the diagnosis message "left operand of comma operator has no effect" (used by GCC) for comma operator.
This also makes Clang diagnose in the constant evaluation context which aligns with GCC/MSVC behavior. (https://godbolt.org/z/7zxb8Tx96)
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D103938
These are intended to mimic warnings available in gcc.
-Wunused-but-set-variable is triggered in the case of a variable which
appears on the LHS of an assignment but not otherwise used.
For instance:
void f() {
int x;
x = 0;
}
-Wunused-but-set-parameter works similarly, but for function parameters
instead of variables.
In C++, they are triggered only for scalar types; otherwise, they are
triggered for all types. This is gcc's behavior.
-Wunused-but-set-parameter is controlled by -Wextra, while
-Wunused-but-set-variable is controlled by -Wunused. This is slightly
different from gcc's behavior, but seems most consistent with clang's
behavior for -Wunused-parameter and -Wunused-variable.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D100581
This patch adds tests for things that happened to be fixed by previous
patches, but that should continue working if we do decide to treat
sizeless types as incomplete types.
Differential Revision: https://reviews.llvm.org/D79584
The built-in SVE types are supposed to be treated as opaque types.
This means that for initialisation purposes they should be treated
as a single unit, much like a scalar type.
However, as Eli pointed out, actually using "scalar" in the diagnostics
is likely to cause confusion, given the types are logically vectors.
The patch therefore uses custom diagnostics or generalises existing
ones. Some of the messages use the word "indivisible" to try to make
it clear(er) that these types can't be initialised elementwise.
I don't think it's possible to trigger warn_braces_around_(scalar_)init
for sizeless types as things stand, since the types can't be used as
members or elements of more complex types. But it seemed better to be
consistent with ext_many_braces_around_(scalar_)init, so the patch
changes it anyway.
Differential Revision: https://reviews.llvm.org/D76689
Built-in SVE types are trivial, since they're trivially copyable
and support default construction.
Differential Revision: https://reviews.llvm.org/D76692
SVE types are trivially copyable: they can be copied simply
by reproducing the byte representation of the source object.
Differential Revision: https://reviews.llvm.org/D76691
Sizeless types can't be used with "new", so it doesn't make sense
to use them with "delete" either. The SVE ACLE therefore doesn't
allow that.
This is slightly stronger than for normal incomplete types, since:
struct S;
void f(S *s) { delete s; }
is (by necessity) just a default-on warning rather than an error.
Differential Revision: https://reviews.llvm.org/D76219
new-expressions for a type T require sizeof(T) to be computable,
so the SVE ACLE does not allow them for sizeless types. At the moment:
auto f() { return new __SVInt8_t; }
creates a call to operator new with a zero size:
%call = call noalias nonnull i8* @_Znwm(i64 0)
This patch reports an appropriate error instead.
Differential Revision: https://reviews.llvm.org/D76218
In the current SVE ACLE spec, the usual rules for throwing and
catching incomplete types also apply to sizeless types. However,
throwing pointers to sizeless types should not pose any real difficulty,
so as an extension, the clang implementation allows that.
This patch enforces these rules for catch statements.
Differential Revision: https://reviews.llvm.org/D76090
Summary:
The same rules for throwing and catching incomplete types also apply
to sizeless types. This patch enforces that for throw statements.
It also make sure that we use "sizeless type" rather "incomplete type"
in the associated message. (Both are correct, but "sizeless type" is
more specific and hopefully more user-friendly.)
The SVE ACLE simply extends the rule for incomplete types to
sizeless types. However, throwing pointers to sizeless types
should not pose any real difficulty, so as an extension,
the clang implementation allows that.
Reviewers: sdesmalen, efriedma, rovka, rjmccall
Subscribers: tschuett, rkruppe, psnobl, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D76088
In the current SVE ACLE spec, the usual rules for throwing and
catching incomplete types also apply to sizeless types. However,
throwing pointers to sizeless types should not pose any real difficulty,
so as an extension, the clang implementation allows that.
This patch enforces these rules for explicit exception specs.
Differential Revision: https://reviews.llvm.org/D76087
This patch completes a trio of changes related to arrays of
sizeless types. It rejects various forms of arithmetic on
pointers to sizeless types, in the same way as for other
incomplete types.
Differential Revision: https://reviews.llvm.org/D76086
clang currently accepts:
__SVInt8_t &foo1(__SVInt8_t *x) { return *x; }
__SVInt8_t &foo2(__SVInt8_t *x) { return x[1]; }
The first function is valid ACLE code and generates correct LLVM IR
(and assembly code). But the second function is invalid for the
same reason that arrays of sizeless types are. Trying to code-generate
the function leads to:
llvm/include/llvm/Support/TypeSize.h:126: uint64_t llvm::TypeSize::getFixedSize() const: Assertion `!IsScalable && "Request for a fixed size on a s
calable object"' failed.
Another problem is that:
template<typename T>
constexpr __SIZE_TYPE__ f(T *x) { return &x[1] - x; }
typedef int arr1[f((int *)0) - 1];
typedef int arr2[f((__SVInt8_t *)0) - 1];
produces:
a.cpp:2:48: warning: subtraction of pointers to type '__SVInt8_t' of zero size has undefined behavior [-Wpointer-arith]
constexpr __SIZE_TYPE__ f(T *x) { return &x[1] - x; }
~~~~~ ^ ~
a.cpp:4:18: note: in instantiation of function template specialization 'f<__SVInt8_t>' requested here
typedef int arr2[f((__SVInt8_t *)0) - 1];
This patch reports an appropriate diagnostic instead.
Differential Revision: https://reviews.llvm.org/D76084
The SVE ACLE doesn't allow arrays of sizeless types. At the moment
clang accepts the TU:
__SVInt8_t x[2];
but trying to code-generate it triggers the LLVM assertion:
llvm/lib/IR/Type.cpp:588: static llvm::ArrayType* llvm::ArrayType::get(llvm::Type*, uint64_t): Assertion `isValidElementType(ElementType) && "Invalid type for array element!"' failed.
This patch reports an appropriate error instead.
The rules are slightly more restrictive than for general incomplete types.
For example:
struct s;
typedef struct s arr[2];
is valid as far as it goes, whereas arrays of sizeless types are
invalid in all contexts. BuildArrayType therefore needs a specific
check for isSizelessType in addition to the usual handling of
incomplete types.
Differential Revision: https://reviews.llvm.org/D76082
Since fields can't have sizeless type, it also doesn't make sense
to capture sizeless types by value in lambda expressions. This patch
makes sure that we diagnose that and that we use "sizeless type" rather
"incomplete type" in the associated message. (Both are correct, but
"sizeless type" is more specific and hopefully more user-friendly.)
Differential Revision: https://reviews.llvm.org/D75738
The SVE ACLE doesn't allow fields to have sizeless type. At the moment
clang accepts things like:
struct s { __SVInt8_t x; } y;
but trying to code-generate it leads to LLVM asserts like:
llvm/include/llvm/Support/TypeSize.h:126: uint64_t llvm::TypeSize::getFixedSize() const: Assertion `!IsScalable && "Request for a fixed size on a scalable object"' failed.
This patch adds an associated clang diagnostic.
Differential Revision: https://reviews.llvm.org/D75737
clang accepts a TU containing just:
__SVInt8_t x;
However, sizeless types are not allowed to have static or thread-local
storage duration and trying to code-generate the TU triggers an LLVM
fatal error:
Globals cannot contain scalable vectors
<vscale x 16 x i8>* @x
fatal error: error in backend: Broken module found, compilation aborted!
This patch adds an associated clang diagnostic.
Differential Revision: https://reviews.llvm.org/D75736
It would be difficult to guarantee atomicity for sizeless types,
so the SVE ACLE makes atomic sizeless types invalid. As it happens,
we already rejected them before the patch, but for the wrong reason:
error: _Atomic cannot be applied to type 'svint8_t' (aka '__SVInt8_t')
which is not trivially copyable
The SVE types should be treated as trivially copyable; a later
patch fixes that.
Differential Revision: https://reviews.llvm.org/D75734
A previous patch rejected alignof for sizeless types. This patch
extends that to cover the "aligned" attribute and _Alignas. Since
sizeless types are not meant to be used for long-term data, cannot
be used in aggregates, and cannot have static storage duration,
there shouldn't be any need to fiddle with their alignment.
Like with alignof, this is a conservative position that can be
relaxed in future if it turns out to be too restrictive.
Differential Revision: https://reviews.llvm.org/D75573
clang current accepts:
void foo1(__SVInt8_t *x, __SVInt8_t *y) { *x = *y; }
void foo2(__SVInt8_t *x, __SVInt8_t *y) {
memcpy(y, x, sizeof(__SVInt8_t));
}
The first function is valid ACLE code and generates correct LLVM IR.
However, the second function is invalid ACLE code and generates a
zero-length memcpy. The point of this patch is to reject the use
of sizeof in the second case instead.
There's no similar wrong-code bug for alignof. However, the SVE ACLE
conservatively treats alignof in the same way as sizeof, just as the
C++ standard does for incomplete types. The idea is that layout of
sizeless types is an implementation property and isn't defined at
the language level.
Implementation-wise, the patch adds a new CompleteTypeKind enum
that controls whether RequireCompleteType & friends accept sizeless
built-in types. For now the default is to maintain the status quo
and accept sizeless types. However, the end of the series will flip
the default and remove the Default enum value.
The patch also adds new ...CompleteSized... wrappers that callers can
use if they explicitly want to reject sizeless types. The callers then
use diagnostics that have an extra 0/1 parameter to indicats whether
the type is sizeless or not.
The idea is to have three cases:
1. calls that explicitly reject sizeless types, with a tweaked diagnostic
for the sizeless case
2. calls that explicitly allow sizeless types
3. normal/old-style calls that don't make an explicit choice either way
Once the default is flipped, the 3. calls will conservatively reject
sizeless types, using the same diagnostic as for other incomplete types.
Differential Revision: https://reviews.llvm.org/D75572
This patch adds C and C++ tests for various uses of SVE types.
The tests cover valid uses that are already (correctly) accepted and
invalid uses that are already (correctly) rejected. Later patches
will expand the tests as they fix other cases.[*]
Some of the tests for invalid uses aren't obviously related to
scalable vectors. Part of the reason for having them is to make
sure that the quality of the error message doesn't regress once/if
the types are treated as incomplete types.
[*] These later patches all fix invalid uses that are being incorrectly
accepted. I don't know of any cases in which valid uses are being
incorrectly rejected. In other words, this series is all about
diagnosing invalid code rather than enabling something new.
Differential Revision: https://reviews.llvm.org/D75571
David Truby