Based on the discussion at [1], this patch adds a Clang flag called
-fexperimental-library that controls whether experimental library
features are provided in libc++. In essence, it links against the
experimental static archive provided by libc++ and defines a feature
that can be picked up by libc++ to enable experimental features.
This ensures that users don't start depending on experimental
(and hence unstable) features unknowingly.
[1]: https://discourse.llvm.org/t/rfc-a-compiler-flag-to-enable-experimental-unstable-language-and-library-features
Differential Revision: https://reviews.llvm.org/D121141
WG21 approved delimited escape sequences and named escape
sequences.
Adjust the extension warnings accordingly, and update
the release notes.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D129664
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.
Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.
The warning is off by default as its likely to be somewhat disruptive
otherwise.
This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D128059
This reverts commit cc309721d2 because it
breaks the following tests on GreenDragon:
TestDataFormatterObjCCF.py
TestDataFormatterObjCExpr.py
TestDataFormatterObjCKVO.py
TestDataFormatterObjCNSBundle.py
TestDataFormatterObjCNSData.py
TestDataFormatterObjCNSError.py
TestDataFormatterObjCNSNumber.py
TestDataFormatterObjCNSURL.py
TestDataFormatterObjCPlain.py
TestDataFormatterObjNSException.py
https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45288/
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.
Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.
The warning is off by default as its likely to be somewhat disruptive
otherwise.
This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D128059
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.
Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.
The warning is off by default as its likely to be somewhat disruptive
otherwise.
This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D128059
This reverts commit 4174f0ca61.
Also revert follow-up "[Clang] Fix invalid utf-8 detection"
This reverts commit bf45e27a67.
The second commit broke tests, see comments on
https://reviews.llvm.org/D129223, and it sounds like the first
commit isn't valid without the second one. So reverting both for now.
The length of valid codepoints was incorrectly
calculated which was not caught before because the
absence of tests for the valid codepoints scenario.
Differential Revision: https://reviews.llvm.org/D129223
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.
Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.
The warning is off by default as its likely to be somewhat disruptive
otherwise.
This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D128059
Introduce an off-by default `-Winvalid-utf8` warning
that detects invalid UTF-8 code units sequences in comments.
Invalid UTF-8 in other places is already diagnosed,
as that cannot appear in identifiers and other grammar constructs.
The warning is off by default as its likely to be somewhat disruptive
otherwise.
This warning allows clang to conform to the yet-to be approved WG21
"P2295R5 Support for UTF-8 as a portable source file encoding"
paper.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D128059
Instead of dumping the string literal (which
quotes it and escape every non-ascii symbol),
we can use the content of the string when it is a
8 byte string.
Wide, UTF-8/UTF-16/32 strings are still completely
escaped, until we clarify how these entities should
behave (cf https://wg21.link/p2361).
`FormatDiagnostic` is modified to escape
non printable characters and invalid UTF-8.
This ensures that unicode characters, spaces and new
lines are properly rendered in static messages.
This make clang more consistent with other implementation
and fixes this tweet
https://twitter.com/jfbastien/status/1298307325443231744 :)
Of note, `PaddingChecker` did print out new lines that were
later removed by the diagnostic printing code.
To be consistent with its tests, the new lines are removed
from the diagnostic.
Unicode tables updated to both use the Unicode definitions
and the Unicode 14.0 data.
U+00AD SOFT HYPHEN is still considered a print character
to match existing practices in terminals, in addition of
being considered a formatting character as per Unicode.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D108469
Instead of dumping the string literal (which
quotes it and escape every non-ascii symbol),
we can use the content of the string when it is a
8 byte string.
Wide, UTF-8/UTF-16/32 strings are still completely
escaped, until we clarify how these entities should
behave (cf https://wg21.link/p2361).
`FormatDiagnostic` is modified to escape
non printable characters and invalid UTF-8.
This ensures that unicode characters, spaces and new
lines are properly rendered in static messages.
This make clang more consistent with other implementation
and fixes this tweet
https://twitter.com/jfbastien/status/1298307325443231744 :)
Of note, `PaddingChecker` did print out new lines that were
later removed by the diagnostic printing code.
To be consistent with its tests, the new lines are removed
from the diagnostic.
Unicode tables updated to both use the Unicode definitions
and the Unicode 14.0 data.
U+00AD SOFT HYPHEN is still considered a print character
to match existing practices in terminals, in addition of
being considered a formatting character as per Unicode.
Reviewed By: aaron.ballman, #clang-language-wg
Differential Revision: https://reviews.llvm.org/D108469
Implements [[ https://wg21.link/p2071r1 | P2071 Named Universal Character Escapes ]] - as an extension in all language mode, the patch not warn in c++23 mode will be done later once this paper is plenary approved (in July).
We add
* A code generator that transforms `UnicodeData.txt` and `NameAliases.txt` to a space efficient data structure that can be queried in `O(NameLength)`
* A set of functions in `Unicode.h` to query that data, including
* A function to find an exact match of a given Unicode character name
* A function to perform a loose (ignoring case, space, underscore, medial hyphen) matching
* A function returning the best matching codepoint for a given string per edit distance
* Support of `\N{}` escape sequences in String and character Literals, with loose and typos diagnostics/fixits
* Support of `\N{}` as UCN with loose matching diagnostics/fixits.
Loose matching is considered an error to match closely the semantics of P2071.
The generated data contributes to 280kB of data to the binaries.
`UnicodeData.txt` and `NameAliases.txt` are not committed to the repository in this patch, and regenerating the data is a manual process.
Reviewed By: tahonermann
Differential Revision: https://reviews.llvm.org/D123064
This is a commit with the following changes:
* Remove `ExcludedPreprocessorDirectiveSkipMapping` and related functionality
Removes `ExcludedPreprocessorDirectiveSkipMapping`; its intended benefit for fast skipping of excluded directived blocks
will be superseded by a follow-up patch in the series that will use dependency scanning lexing for the same purpose.
* Refactor dependency scanning to produce pre-lexed preprocessor directive tokens, instead of minimized sources
Replaces the "source minimization" mechanism with a mechanism that produces lexed dependency directives tokens.
* Make the special lexing for dependency scanning a first-class feature of the `Preprocessor` and `Lexer`
This is bringing the following benefits:
* Full access to the preprocessor state during dependency scanning. E.g. a component can see what includes were taken and where they were located in the actual sources.
* Improved performance for dependency scanning. Measurements with a release+thin-LTO build shows ~ -11% reduction in wall time.
* Opportunity to use dependency scanning lexing to speed-up skipping of excluded conditional blocks during normal preprocessing (as follow-up, not part of this patch).
For normal preprocessing measurements show differences are below the noise level.
Since, after this change, we don't minimize sources and pass them in place of the real sources, `DependencyScanningFilesystem` is not technically necessary, but it has valuable performance benefits for caching file `stat`s along with the results of scanning the sources. So the setup of using the `DependencyScanningFilesystem` during a dependency scan remains.
Differential Revision: https://reviews.llvm.org/D125486
Differential Revision: https://reviews.llvm.org/D125487
Differential Revision: https://reviews.llvm.org/D125488
This adds an extension warning when using the preprocessor conditionals
in a language mode they're not officially supported in, and an opt-in
warning for compatibility with previous standards.
Fixes#55306
Differential Revision: https://reviews.llvm.org/D125178
CUDA/HIP programs use __noinline__ like a keyword e.g.
__noinline__ void foo() {} since __noinline__ is defined
as a macro __attribute__((noinline)) in CUDA/HIP runtime
header files.
However, gcc and clang supports __attribute__((__noinline__))
the same as __attribute__((noinline)). Some C++ libraries
use __attribute__((__noinline__)) in their header files.
When CUDA/HIP programs include such header files,
clang will emit error about invalid attributes.
This patch fixes this issue by supporting __noinline__ as
a keyword, so that CUDA/HIP runtime could remove
the macro definition.
Reviewed by: Aaron Ballman, Artem Belevich
Differential Revision: https://reviews.llvm.org/D124866
Currently if a lexically-valid UCN encodes an invalid codepoint, then we
diagnose that, and then hit an assertion while trying to decode it.
Since there isn't anything preventing us reaching this state, remove the
assertion. expandUCNs("X\UAAAAAAAAY") will produce "XY".
Differential Revision: https://reviews.llvm.org/D125059
This reverts commit f6dff93641.
This diagnostic is also in the -Wcomment group, which is in the -Wall
group, so the diagnostic is enabled in a wider context than GCC does.
That turns out to be disruptive for the Linux kernel builds still using
-std=gnu89 because the kernel requires C source files to start with //
comments: https://kernel.org/doc/html/v5.18-rc5/process/license-rules.html#license-identifier-syntax
GCC warns with a pedantic warning when -std=gnu89, but Clang would only
diagnose in -std=c89 mode. Clang now matches the GCC behavior in both
modes.
Fixes#18427
Currently, enablement of heap MTE on Android is specified by an ELF note, which
signals to the linker to enable heap MTE. This change allows
-fsanitize=memtag-heap to synthesize these notes, rather than adding them
through the build system. We need to extend this feature to also signal the
linker to do special work for MTE globals (in future) and MTE stack (currently
implemented in the toolchain, but not implemented in the loader).
Current Android uses a non-backwards-compatible ELF note, called
".note.android.memtag". Stack MTE is an ABI break anyway, so we don't mind that
we won't be able to run executables with stack MTE on Android 11/12 devices.
The current expectation is to support the verbiage used by Android, in
that "SYNC" means MTE Synchronous mode, and "ASYNC" effectively means
"fast", using the Kernel auto-upgrade feature that allows
hardware-specific and core-specific configuration as to whether "ASYNC"
would end up being Asynchronous, Asymmetric, or Synchronous on that
particular core, whichever has a reasonable performance delta. Of
course, this is platform and loader-specific.
Differential Revision: https://reviews.llvm.org/D118948
Allow goto, labelled statements as well as `static`, `thread_local`, and
non-literal variables in `constexpr` functions.
As specified. for all of the above (except labelled statements) constant
evaluation of the construct still fails.
For `constexpr` bodies, the proposal is implemented with diagnostics as
a language extension in older language modes. For determination of
whether a lambda body satisfies the requirements for a constexpr
function, the proposal is implemented only in C++2b mode to retain the
semantics of older modes for programs conforming to them.
Reviewed By: aaron.ballman, hubert.reinterpretcast, erichkeane
Differential Revision: https://reviews.llvm.org/D111400
@mgehre-amd pointed out the following post-commit review feedback on
the changes in 8cba72177dcd8de5d37177dbaf2347e5c1f0f1e8:
As an example, the paper says 3wb /* Yields an _BitInt(3); two value
bits, one sign bit */.
So I would expect that 0xFwb gives _BitInt(5); four value bits, one
sign bit, but with this implementation I get _BitInt(2).
This is because ResultVal as 4 bits, and getMinSignedBits() inteprets
it as negative and thus says that 1 bit is enough to represent -1.
This corrects the behavior for calculating the bit-width and adds some
test coverage.
WG14 adopted N2775 (http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2775.pdf)
at our Feb 2022 meeting. This paper adds a literal suffix for
bit-precise types that automatically sizes the bit-precise type to be
the smallest possible legal _BitInt type that can represent the literal
value. The suffix chosen is wb (for a signed bit-precise type) which
can be combined with the u suffix (for an unsigned bit-precise type).
The preprocessor continues to operate as-if all integer types were
intmax_t/uintmax_t, including bit-precise integer types. It is a
constraint violation if the bit-precise literal is too large to fit
within that type in the context of the preprocessor (when still using
a pp-number preprocessing token), but it is not a constraint violation
in other circumstances. This allows you to make bit-precise integer
literals that are wider than what the preprocessor currently supports
in order to initialize variables, etc.
This new flag enables `__has_feature(cxx_unstable)` that would replace libc++ macros for individual unstable/experimental features, e.g. `_LIBCPP_HAS_NO_INCOMPLETE_RANGES` or `_LIBCPP_HAS_NO_INCOMPLETE_FORMAT`.
This would make it easier and more convenient to opt-in into all libc++ unstable features at once.
Differential Revision: https://reviews.llvm.org/D120160
A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,
void func();
becomes
void func(void);
This is the sixth batch of tests being updated (there are a significant
number of other tests left to be updated).
When a -W<diag> option is given on the command line, and the corresponding diagnostic has
the NoWarnOnError flag set, prevent the flag from being dropped when the severity is reevaluated.
This fixes PR51837.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D109981
Now in libcxx and clang, all the coroutine components are defined in
std::experimental namespace.
And now the coroutine TS is merged into C++20. So in the working draft
like N4892, we could find the coroutine components is defined in std
namespace instead of std::experimental namespace.
And the coroutine support in clang seems to be relatively stable. So I
think it may be suitable to move the coroutine component into the
experiment namespace now.
This patch would make clang lookup coroutine_traits in std namespace
first. For the compatibility consideration, clang would lookup in
std::experimental namespace if it can't find definitions in std
namespace. So the existing codes wouldn't be break after update
compiler.
And in case the compiler found std::coroutine_traits and
std::experimental::coroutine_traits at the same time, it would emit an
error for it.
The support for looking up std::experimental::coroutine_traits would be
removed in Clang16.
Reviewed By: lxfind, Quuxplusone
Differential Revision: https://reviews.llvm.org/D108696
This reverts commit 2d7fba5f95.
The patch was reverted because it caused regression with rocThrust
due to ambiguity of template specialization.
For details please see https://reviews.llvm.org/D109496
The #pragma directives push_macro/pop_macro and include_alias may influence the #include / import directives encountered by dependency scanning tools like clang-scan-deps.
This patch ensures that those directives are not removed during source code minimization.
Differential Revision: https://reviews.llvm.org/D112088
A resolution to the ambiguity issues created by P0522, which is a DR solving
CWG 150, did not come as expected, so we are just going to accept the change,
and watch how users digest it.
For now we deprecate the flag with a warning, and make it on by default.
We don't remove the flag completely in order to give users a chance to
work around any problems by disabling it.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D109496
This patch adds a new preprocessor extension ``#pragma clang final``
which enables warning on undefinition and re-definition of macros.
The intent of this warning is to extend beyond ``-Wmacro-redefined`` to
warn against any and all alterations to macros that are marked `final`.
This warning is part of the ``-Wpedantic-macros`` diagnostics group.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D108567
Specify the C and C++ standards explicitly for this test. This avoids
failures for drivers that default to older standards.
Differential Revision: https://reviews.llvm.org/D109857
\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 patch adds `#pragma clang restrict_expansion ` to enable flagging
macros as unsafe for header use. This is to allow macros that may have
ABI implications to be avoided in headers that have ABI stability
promises.
Using macros in headers (particularly public headers) can cause a
variety of issues relating to ABI and modules. This new pragma logs
warnings when using annotated macros outside the main source file.
This warning is added under a new diagnostics group -Wpedantic-macros
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D107095
This implements P2362, which has not yet been approved by the
C++ committee, but because wide-multi character literals are
implementation defined, clang might not have to wait for WG21.
This change is also being applied in C mode as the behavior is
implementation-defined in C as well and there's no benefit to
having different rules between the languages.
The other part of P2362, making non-representable character
literals ill-formed, is already implemented by clang
The interesting bit about that triple isn't the architecture, it's the
fact that ps4 implies C99 as the standard rather than a newer C mode.
Specify the language standard rather than the triple so the test is a
bit more general.
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 adds `#pragma clang deprecated` to enable deprecation of
preprocessor macros.
The macro must be defined before `#pragma clang deprecated`. When
deprecating a macro a custom message may be optionally provided.
Warnings are emitted at the use site of a deprecated macro, and can be
controlled via the `-Wdeprecated` warning group.
This patch takes some rough inspiration and a few lines of code from
https://reviews.llvm.org/D67935.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D106732
The feature was implemented in D99005, but we forgot to add the test
macro.
Reviewed By: Quuxplusone
Differential Revision: https://reviews.llvm.org/D104984
Louis Dionne