There was some confusion during the discussion of a patch as to whether
`any` can be used to blast an attribute with no subject list onto
basically everything in a program by not specifying a subrule. This
patch adds documentation and tests to make it clear that this situation
is not supported and will be diagnosed.
Based on post-commit review discussion on
2bd8493847 with Richard Smith.
Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).
This was originally committed in 277623f4d5
Reverted in f9ad1d1c77 due to breakages
outside of clang - lldb seems to have some strange/strong dependence on
"char [N]" versus "char[N]" when printing strings (not due to that name
appearing in DWARF, but probably due to using clang to stringify type
names) that'll need to be addressed, plus a few other odds and ends in
other subprojects (clang-tools-extra, compiler-rt, etc).
The clang behavior was poor before this patch:
```
void B::foo() override {}
// Before: clang emited "expcted function body after function
// declarator", and skiped all contents until it hits a ";", the
// following function f() is discarded.
// VS
// Now "override is not allowed" with a remove fixit, and following f()
// is retained.
void f();
```
Differential Revision: https://reviews.llvm.org/D111883
Looks like lldb has some issues with this - somehow it causes lldb to
treat a "char[N]" type as an array of chars (prints them out
individually) but a "char [N]" is printed as a string. (even though the
DWARF doesn't have this string in it - it's something to do with the
string lldb generates for itself using clang)
This reverts commit 277623f4d5.
Based on post-commit review discussion on
2bd8493847 with Richard Smith.
Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).
(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
C++17 permits using 'typename' or 'class' for a template template
parameter, but the error message in the parser only refers to 'class'.
This patch, in C++17 or newer modes, adds "or 'template'" to the
diagnostic.
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
\x{XXXX} \u{XXXX} and \o{OOOO} are accepted in all languages mode
in characters and string literals.
This is a feature proposed for both C++ (P2290R1) and C (N2785). The
papers have been seen by both committees but are not yet adopted into
either standard. However, they do have support from both committees.
This adds the Unicode 13 data for XID_Start and XID_Continue.
The definition of valid identifier is changed in all C++ modes
as P1949 (https://wg21.link/p1949) was accepted by WG21 as a defect
report.
This patch implements P2092
Simple requirements in requirement body shall not start with requires.
A warning was already in place so we just turn this warning into an error.
In addition, we add tests to make sure typename is optional in
requirement-parameter-list as per the same paper.
Currently, we prohibit this pragma from appearing within a language
linkage specification, but this is useful functionality that is
supported by MSVC (which is where we inherited this feature from).
This patch allows you to use the pragma within an extern "C" {} (etc)
block.
Set default version for OpenCL C to 1.2. This means that the
absence of any standard flag will be equivalent to passing
'-cl-std=CL1.2'.
Note that this patch also fixes incorrect version check for
the pointer to pointer kernel arguments diagnostic and
atomic test.
Differential Revision: https://reviews.llvm.org/D106504
This reverts commit 52aeacfbf5.
There isn't full agreement on a path forward yet, but there is agreement that
this shouldn't land as-is. See discussion on https://reviews.llvm.org/D105338
Also reverts unreviewed "[clang] Improve `-Wnull-dereference` diag to be more in-line with reality"
This reverts commit f4877c78c0.
And all the related changes to tests:
This reverts commit 9a0152799f.
This reverts commit 3f7c9cc274.
This reverts commit 329f8197ef.
This reverts commit aa9f58cc2c.
This reverts commit 2df37d5ddd.
This reverts commit a72a441812.
Word on the grapevine was that the committee had some discussion that
ended with unanimous agreement on eliminating relational function pointer comparisons.
We wanted to be bold and just ban all of them cold turkey.
But then we chickened out at the last second and are going for
eliminating just the spaceship overload candidate instead, for now.
See D104680 for reference.
This should be fine and "safe", because the only possible semantic change this
would cause is that overload resolution could possibly be ambiguous if
there was another viable candidate equally as good.
But to save face a little we are going to:
* Issue an "error" for three-way comparisons on function pointers.
But all this is doing really is changing one vague error message,
from an "invalid operands to binary expression" into an
"ordered comparison of function pointers", which sounds more like we mean business.
* Otherwise "warn" that comparing function pointers like that is totally
not cool (unless we are told to keep quiet about this).
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D104892
This attribute applies to a using declaration, and permits importing a
declaration without knowing if that declaration exists. This is useful
for libc++ C wrapper headers that re-export declarations in std::, in
cases where the base C library doesn't provide all declarations.
This attribute was proposed in http://lists.llvm.org/pipermail/cfe-dev/2020-June/066038.html.
rdar://69313357
Differential Revision: https://reviews.llvm.org/D90188
Currently clang and nvcc use c++14 as default std for C++.
gcc 11 even uses c++17 as default std for C++. However,
clang uses c++98 as default std for CUDA/HIP.
As c++14 has been well adopted and became default for
clang, it seems reasonable to use c++14 as default std
for CUDA/HIP.
Reviewed by: Artem Belevich
Differential Revision: https://reviews.llvm.org/D103221
This is a re-application of dc67299 which was reverted in f63adf5b because
it broke the build. The issue should now be fixed.
Attribution note: The original author of this patch is Erik Pilkington.
I'm only trying to land it after rebasing.
Differential Revision: https://reviews.llvm.org/D91630
this patch fixes Bug 27113 by adding support for string literals to the
implementation of the MS extension __identifier.
Differential revision: https://reviews.llvm.org/D100252
Summary:
Call TryAltiVecVectorToken when an identifier is seen in the parser before
annotating the token. This checks the next token where necessary to ensure
that vector is properly handled as the altivec token.
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: ZarkoCA (Zarko Todorovski)
Differential Revision: https://reviews.llvm.org/D100991
Remove requirements on extension pragma in atomic types
because it has not respected the spec wrt disabling types
and hasn't been useful either. With this change, the
developers can use atomic types from the extensions if they
are supported without enabling the pragma just like the builtin
functions
This patch does not break backward compatibility since the
extension pragma is still supported and it makes the behavior of
the compiler less strict by accepting code without needless and
inconsistent pragma statements.
Differential Revision: https://reviews.llvm.org/D100976
Currently when including stdbool.h and altivec.h declaration of `vector bool` leads to
errors due to `bool` being expanded to '_Bool`. This patch allows the parser
to recognize `_Bool`.
Reviewed By: hubert.reinterpretcast, Everybody0523
Differential Revision: https://reviews.llvm.org/D102064
Double square bracket attribute arguments can be arbitrarily complex,
and the attribute argument parsing logic recovers by skipping tokens.
As a fallback recovery mechanism, parse recovery stops before reading a
semicolon. This could lead to an infinite loop in the attribute list
parsing logic.
Clang currently has a bug where it allows you to write [[foo bar]] and
both attributes are silently accepted. This patch corrects the comma
parsing rules for such attributes and handles the test case fallout, as
a few tests were accidentally doing this.
Set the source ranges for parsed GNU-style attributes in
ParseGNUAttributes(), the same way that ParseCXX11Attributes() does it.
Differential Revision: https://reviews.llvm.org/D75844
... instantiations
They are currently not being diagnosed because ProhibitAttributes() does
not handle attribute lists with an invalid source range. But once it
does, we need to allow GNU attributes in this place.
Additionally, start optionally diagnosing empty attr lists in
ProhibitCXX11Attributes(), since ProhibitAttribute() does it.
Differential Revision: https://reviews.llvm.org/D97362
Clang currently automates a fair amount of diagnostic checking for
declaration attributes based on the declarations in Attr.td. It checks
for things like subject appertainment, number of arguments, language
options, etc. This patch uses the same machinery to perform diagnostic
checking on statement attributes.
The condition variable is in scope in the loop increment, so we need to
emit the jump destination from wthin the scope of the condition
variable.
For GCC compatibility (and compatibility with real-world 'FOR_EACH'
macros), 'continue' is permitted in a statement expression within the
condition of a for loop, though, so there are two cases here:
* If the for loop has no condition variable, we can emit the jump
destination before emitting the condition.
* If the for loop has a condition variable, we must defer emitting the
jump destination until after emitting the variable. We diagnose a
'continue' appearing in the initializer of the condition variable,
because it would jump past the initializer into the scope of that
variable.
Reviewed By: rjmccall
Differential Revision: https://reviews.llvm.org/D98816
As a follow-up to D95691, add new diagnostic groups named
pre-c++N-compat to replace the old diagnostic groups with the standards
listed out explicitly. The old group names are retained for backwards
compatibility.
There is no need to check for enabled pragma for core or optional core features,
thus this check is removed
Reviewed By: Anastasia
Differential Revision: https://reviews.llvm.org/D97058
Prior to this fix, constrained decltype(auto) behaves exactly the same
as constrained regular auto.
This fixes it so it deduces like decltype(auto).
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D98087
https://wg21.link/P2173 is making its way through WG21 currently and
has not been formally adopted yet. This feature provides very useful
functionality in that you can specify attributes on the various
function *declarations* generated by a lambda expression, where the
current C++ grammar only allows attributes which apply to the various
function *types* so generated.
This patch implements P2173 on the assumption that it will be adopted
by WG21 with this syntax for C++23.
Our diagnostics relating to static assertions were a bit confused. For
instance, when in MS compatibility mode in C (where we accept
static_assert even without including <assert.h>), we would fail
to warn the user that they were using the wrong spelling (even in
pedantic mode), we were missing a compatibility warning about using
_Static_assert in earlier standards modes, diagnostics for the optional
message were not reflected in C as they were in C++, etc.
Aaron Ballman