user interface and documentation, and update __cplusplus for C++20.
WG21 considers the C++20 standard to be finished (even though it still
has some more steps to pass through in the ISO process).
The old flag names are accepted for compatibility, as usual, and we
still have lots of references to C++2a in comments and identifiers;
those can be cleaned up separately.
Also add extension warnings for the cases that are disallowed by the
current rules for destructor name lookup, refactor and simplify the
lookup code, and improve the diagnostic quality when lookup fails.
The special case we previously supported for converting
p->N::S<int>::~S() from naming a class template into naming a
specialization thereof is subsumed by a more general rule here (which is
also consistent with Clang's historical behavior and that of other
compilers): if we can't find a suitable S in N, also look in N::S<int>.
The extension warnings are off by default, except for a warning when
lookup for p->N::S::~T() looks for T in scope instead of in N (or N::S).
That seems sufficiently heinous to warn on by default, especially since
we can't support it for a dependent nested-name-specifier.
whether a call is to a builtin.
We already had a general mechanism to do this but for some reason
weren't using it. In passing, check for the other unary operators that
can intervene in a reasonably-direct function call (we already handled
'&' but missed '*' and '+').
This reverts commit aaae6b1b61,
reinstating af80b8ccc5, with a fix to
clang-tidy.
isDeclarationSpecifiers did not handle some cases of placeholder-type-specifiers with
type-constraints, causing parsing bugs in abbreviated constructor templates.
Add comprehensive handling of type-constraints to isDeclarationSpecifier.
whether a call is to a builtin.
We already had a general mechanism to do this but for some reason
weren't using it. In passing, check for the other unary operators that
can intervene in a reasonably-direct function call (we already handled
'&' but missed '*' and '+').
See
https://docs.google.com/document/d/1xMkTZMKx9llnMPgso0jrx3ankI4cv60xeZ0y4ksf4wc/preview
for background discussion.
This adds a warning, flags and pragmas to limit the number of
pre-processor tokens either at a certain point in a translation unit, or
overall.
The idea is that this would allow projects to limit the size of certain
widely included headers, or for translation units overall, as a way to
insert backstops for header bloat and prevent compile-time regressions.
Differential revision: https://reviews.llvm.org/D72703
The code for parsing of type-constraints in compound-requirements was not adapted for the new TryAnnotateTypeConstraint which
caused compound-requirements with scope specifiers to ignore them.
Also add regression tests for scope specifiers in type-constraints in more contexts.
Now with concepts support merged and mostly complete, we do not need -fconcepts-ts
(which was also misleading as we were not implementing the TS) and can enable
concepts features under C++2a. A warning will be generated if users still attempt
to use -fconcepts-ts.
This patch implements P1141R2 "Yet another approach for constrained declarations".
General strategy for this patch was:
- Expand AutoType to include optional type-constraint, reflecting the wording and easing the integration of constraints.
- Replace autos in parameter type specifiers with invented parameters in GetTypeSpecTypeForDeclarator, using the same logic
previously used for generic lambdas, now unified with abbreviated templates, by:
- Tracking the template parameter lists in the Declarator object
- Tracking the template parameter depth before parsing function declarators (at which point we can match template
parameters against scope specifiers to know if we have an explicit template parameter list to append invented parameters
to or not).
- When encountering an AutoType in a parameter context we check a stack of InventedTemplateParameterInfo structures that
contain the info required to create and accumulate invented template parameters (fields that were already present in
LambdaScopeInfo, which now inherits from this class and is looked up when an auto is encountered in a lambda context).
Resubmit after fixing MSAN failures caused by incomplete initialization of AutoTypeLocs in TypeSpecLocFiller.
Differential Revision: https://reviews.llvm.org/D65042
This patch implements P1141R2 "Yet another approach for constrained declarations".
General strategy for this patch was:
- Expand AutoType to include optional type-constraint, reflecting the wording and easing the integration of constraints.
- Replace autos in parameter type specifiers with invented parameters in GetTypeSpecTypeForDeclarator, using the same logic
previously used for generic lambdas, now unified with abbreviated templates, by:
- Tracking the template parameter lists in the Declarator object
- Tracking the template parameter depth before parsing function declarators (at which point we can match template
parameters against scope specifiers to know if we have an explicit template parameter list to append invented parameters
to or not).
- When encountering an AutoType in a parameter context we check a stack of InventedTemplateParameterInfo structures that
contain the info required to create and accumulate invented template parameters (fields that were already present in
LambdaScopeInfo, which now inherits from this class and is looked up when an auto is encountered in a lambda context).
Resubmit after incorrect check in NonTypeTemplateParmDecl broke lldb.
Differential Revision: https://reviews.llvm.org/D65042
This patch implements P1141R2 "Yet another approach for constrained declarations".
General strategy for this patch was:
- Expand AutoType to include optional type-constraint, reflecting the wording and easing the integration of constraints.
- Replace autos in parameter type specifiers with invented parameters in GetTypeSpecTypeForDeclarator, using the same logic
previously used for generic lambdas, now unified with abbreviated templates, by:
- Tracking the template parameter lists in the Declarator object
- Tracking the template parameter depth before parsing function declarators (at which point we can match template
parameters against scope specifiers to know if we have an explicit template parameter list to append invented parameters
to or not).
- When encountering an AutoType in a parameter context we check a stack of InventedTemplateParameterInfo structures that
contain the info required to create and accumulate invented template parameters (fields that were already present in
LambdaScopeInfo, which now inherits from this class and is looked up when an auto is encountered in a lambda context).
Differential Revision: https://reviews.llvm.org/D65042
Implement support for C++2a requires-expressions.
Re-commit after compilation failure on some platforms due to alignment issues with PointerIntPair.
Differential Revision: https://reviews.llvm.org/D50360
A TemplateIdAnnotation represents only a template-id, not a
nested-name-specifier plus a template-id. Don't make a redundant copy of
the CXXScopeSpec and store it on the template-id annotation.
This slightly improves error recovery by more properly handling the case
where we would form an invalid CXXScopeSpec while parsing a typename
specifier, instead of accidentally putting the token stream into a
broken "annot_template_id with a scope specifier, but with no preceding
annot_cxxscope token" state.
Add support for type-constraints in template type parameters.
Also add support for template type parameters as pack expansions (where the type constraint can now contain an unexpanded parameter pack).
Differential Revision: https://reviews.llvm.org/D44352
Function trailing requires clauses now parsed, supported in overload resolution and when calling, referencing and taking the address of functions or function templates.
Differential Revision: https://reviews.llvm.org/D43357
An empty string literal in an asm label does not make a whole lot of sense. GCC
does not diagnose such a construct, but it also generates code that cannot be
assembled by gas should two symbols have an empty asm label within the same TU.
This does not affect an asm statement with an empty string literal, which is
still a useful construct.
Summary:
this allow much better support of codebases like the linux kernel that mix tabs and spaces.
-ftabstop=//Width// allow specifying how large tabs are considered to be.
Reviewers: xbolva00, aaron.ballman, rsmith
Reviewed By: aaron.ballman
Subscribers: mstorsjo, cfe-commits, jyknight, riccibruno, rsmith, nathanchance
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71037
This reverts commit b47b35ff51.
This caused failed asserts (Assertion `FIDAndOffset.second >
ColNo && "Column number smaller than file offset?"' failed.)
on a source file with a single line containing
"int main (void) { for( int i = 0; i < 9; i++ ); return 0; }".
Summary:
Amend MS offset operator implementation, to more closely fit with its MS counterpart:
1. InlineAsm: evaluate non-local source entities to their (address) location
2. Provide a mean with which one may acquire the address of an assembly label via MS syntax, rather than yielding a memory reference (i.e. "offset asm_label" and "$asm_label" should be synonymous
3. address PR32530
Based on http://llvm.org/D37461
Fix broken test where the break appears unrelated.
- Set up appropriate memory-input rewrites for variable references.
- Intel-dialect assembly printing now correctly handles addresses by adding "offset".
- Pass offsets as immediate operands (using "r" constraint for offsets of locals).
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D71436
Summary:
this allow much better support of codebases like the linux kernel that mix tabs and spaces.
-ftabstop=//Width// allow specifying how large tabs are considered to be.
Reviewers: xbolva00, aaron.ballman, rsmith
Reviewed By: aaron.ballman
Subscribers: jyknight, riccibruno, rsmith, nathanchance
Differential Revision: https://reviews.llvm.org/D71037
Add printing of __private address space to TypePrinter to allow
it appears in diagnostics and AST dumps as all other language
addr spaces.
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71272
classification.
We were accidentally treating invalid scope specs as being empty,
resulting in our trying to form an ADL-only call with a qualified
callee, which tripped up an assert later on.
Before when the overflow occured an assertion was triggered. Now check
whether the maximum has been reached and warn properly.
This patch fixes the original submission of PR19607.
Differential Revision: https://reviews.llvm.org/D63975
Part of C++20 Concepts implementation effort. Added Concept Specialization Expressions that are created when a concept is refe$
D41217 on Phabricator.
(recommit after fixing failing Parser test on windows)
llvm-svn: 374903
Part of C++20 Concepts implementation effort. Added Concept Specialization Expressions that are created when a concept is referenced with arguments, and tests thereof.
llvm-svn: 374882
Summary:
C++ does not allow shadowing template parameters, but previously we
allowed it under -fms-extensions. Now this behavior is controlled by
-fms-compatibility, and we emit a -Wmicrosoft-template warning when it
happens.
Fixes PR43265
Reviewers: thakis, hans
Subscribers: amccarth, rsmith, STL_MSFT, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67463
llvm-svn: 371753
This reverts r371497 (git commit 3d7e9ab7b9)
Reorder `not` with `env` in these two tests so they pass:
Driver/rewrite-map-in-diagnostics.c
Index/crash-recovery-modules.m.
This will not be necessary after D66531 lands.
llvm-svn: 371552
I see in the history for some of these tests REQUIRES:shell was used as
a way to disable tests on Windows because they are flaky there. I tried
not to re-enable such tests, but it's possible that I missed some and
this will re-enable flaky tests on Windows. If so, we should disable
them with UNSUPPORTED:system-windows and add a comment that they are
flaky there. So far as I can tell, the lit internal shell is capable of
running all of these tests, and we shouldn't use REQUIRES:shell as a
proxy for Windows.
llvm-svn: 371478
This is mostly the same as the
[[clang::require_constant_initialization]] attribute, but has a couple
of additional syntactic and semantic restrictions.
In passing, I added a warning for the attribute form being added after
we have already seen the initialization of the variable (but before we
see the definition); that case previously slipped between the cracks and
the attribute was silently ignored.
llvm-svn: 370972
initializers.
This has some interesting interactions with our existing extensions to
support C99 designated initializers as an extension in C++. Those are
resolved as follows:
* We continue to permit the full breadth of C99 designated initializers
in C++, with the exception that we disallow a partial overwrite of an
initializer with a non-trivially-destructible type. (Full overwrite
is OK, because we won't run the first initializer at all.)
* The C99 extensions are disallowed in SFINAE contexts and during
overload resolution, where they could change the meaning of valid
programs.
* C++20 disallows reordering of initializers. We only check for that for
the simple cases that the C++20 rules permit (designators of the form
'.field_name =' and continue to allow reordering in other cases).
It would be nice to improve this behavior in future.
* All C99 designated initializer extensions produce a warning by
default in C++20 mode. People are going to learn the C++ rules based
on what Clang diagnoses, so it's important we diagnose these properly
by default.
* In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and
so still diagnose C99 extensions as described above. We continue to
accept designated C++20-compatible initializers in C++ <= 17 silently
by default (but naturally still reject under -pedantic-errors).
This is not a complete implementation of P0329R4. In particular, that
paper introduces new non-C99-compatible syntax { .field { init } }, and
we do not support that yet.
This is based on a previous patch by Don Hinton, though I've made
substantial changes when addressing the above interactions.
Differential Revision: https://reviews.llvm.org/D59754
llvm-svn: 370544
If a class or struct or union declaration contains a pragma that
is not valid in this context, compiler issues generic error like
"expected member name or ';' after declaration specifiers". With this
change the error tells that this pragma cannot appear in this declaration.
Differential Revision: https://reviews.llvm.org/D64932
llvm-svn: 367779
Rename lang mode flag to -cl-std=clc++/-cl-std=CLC++
or -std=clc++/-std=CLC++.
This aligns with OpenCL C conversion and removes ambiguity
with OpenCL C++.
Differential Revision: https://reviews.llvm.org/D65102
llvm-svn: 367008
This adds a new vectorize predication loop hint:
#pragma clang loop vectorize_predicate(enable)
that can be used to indicate to the vectoriser that all (load/store)
instructions should be predicated (masked). This allows, for example, folding
of the remainder loop into the main loop.
This patch will be followed up with D64916 and D65197. The former is a
refactoring in the loopvectorizer and the groundwork to make tail loop folding
a more general concept, and in the latter the actual tail loop folding
transformation will be implemented.
Differential Revision: https://reviews.llvm.org/D64744
llvm-svn: 366989
If the type didn't exist, we used to emit a really bad error:
t.m:3:12: error: expected ')'
-(nullable NoSuchType)foo3;
^
rdar://50925632
llvm-svn: 364489
Syntax:
asm [volatile] goto ( AssemblerTemplate
:
: InputOperands
: Clobbers
: GotoLabels)
https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html
New llvm IR is "callbr" for inline asm goto instead "call" for inline asm
For:
asm goto("testl %0, %0; jne %l1;" :: "r"(cond)::label_true, loop);
IR:
callbr void asm sideeffect "testl $0, $0; jne ${1:l};", "r,X,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@foo, %label_true), i8* blockaddress(@foo, %loop)) #1
to label %asm.fallthrough [label %label_true, label %loop], !srcloc !3
asm.fallthrough:
Compiler need to generate:
1> a dummy constarint 'X' for each label.
2> an unique fallthrough label for each asm goto stmt " asm.fallthrough%number".
Diagnostic
1> duplicate asm operand name are used in output, input and label.
2> goto out of scope.
llvm-svn: 362045
message sends, designators, and attributes.
Instead of having the tentative parsing phase sometimes return an
indicator to say what diagnostic to produce if parsing fails and
sometimes ask the caller to run it again, consistently ask the caller to
try parsing again if tentative parsing would fail or is otherwise unable
to completely parse the lambda-introducer without producing an
irreversible semantic effect.
Mostly NFC, but we should recover marginally better in some error cases
(avoiding duplicate diagnostics).
llvm-svn: 361182
Summary:
This adds a new error for missing parentheses around lambdas in delete operators.
```
int main() {
delete []() { return new int(); }();
}
```
This will result in:
```
test.cpp:2:3: error: '[]' after delete interpreted as 'delete[]'
delete []() { return new int(); }();
^~~~~~~~~
test.cpp:2:9: note: add parentheses around the lambda
delete []() { return new int(); }();
^
( )
```
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: riccibruno, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D36357
llvm-svn: 361119
object rather than tracking the originating expression.
This is groundwork for supporting polymorphic typeid expressions. (Note
that this somewhat regresses our support for DR1968, but it turns out
that that never actually worked anyway, at least in non-trivial cases.)
This reinstates r360974, reverted in r360988, with a fix for a
static_assert failure on 32-bit builds: force Type base class to have
8-byte alignment like the rest of Clang's AST nodes.
llvm-svn: 360995
object rather than tracking the originating expression.
This is groundwork for supporting polymorphic typeid expressions. (Note
that this somewhat regresses our support for DR1968, but it turns out
that that never actually worked anyway, at least in non-trivial cases.)
llvm-svn: 360974
Summary:
This patch implements the source location builtins `__builtin_LINE(), `__builtin_FUNCTION()`, `__builtin_FILE()` and `__builtin_COLUMN()`. These builtins are needed to implement [`std::experimental::source_location`](https://rawgit.com/cplusplus/fundamentals-ts/v2/main.html#reflection.src_loc.creation).
With the exception of `__builtin_COLUMN`, GCC also implements these builtins, and Clangs behavior is intended to match as closely as possible.
Reviewers: rsmith, joerg, aaron.ballman, bogner, majnemer, shafik, martong
Reviewed By: rsmith
Subscribers: rnkovacs, loskutov, riccibruno, mgorny, kunitoki, alexr, majnemer, hfinkel, cfe-commits
Differential Revision: https://reviews.llvm.org/D37035
llvm-svn: 360937
(and less wrong).
It's not correct to assume that X<something, Type> is always a
template-id; there are a few cases where the comma takes us into a
non-expression syntactic context in which 'Type' might be permissible.
Stop doing that.
This slightly regresses our error recovery on the cases where the
construct is intended to be a template-id. We typically do still manage
to diagnose a missing 'template' keyword, but we realize this too late
to properly recover from the error.
This fixes a regression introduced by r360308.
llvm-svn: 360827
This can be used for better support of `-fno-gnu-inline-asm` builds.
rdar://problem/49540880
Reviewers: aaron.ballman, rsmith
Reviewed By: aaron.ballman
Subscribers: eraman, jkorous, dexonsmith, craig.topper, cfe-commits
Differential Revision: https://reviews.llvm.org/D61619
llvm-svn: 360625
template name is not visible to unqualified lookup.
In order to support this without a severe degradation in our ability to
diagnose typos in template names, this change significantly restructures
the way we handle template-id-shaped syntax for which lookup of the
template name finds nothing.
Instead of eagerly diagnosing an undeclared template name, we now form a
placeholder template-name representing a name that is known to not find
any templates. When the parser sees such a name, it attempts to
disambiguate whether we have a less-than comparison or a template-id.
Any diagnostics or typo-correction for the name are delayed until its
point of use.
The upshot should be a small improvement of our diagostic quality
overall: we now take more syntactic context into account when trying to
resolve an undeclared identifier on the left hand side of a '<'. In
fact, this works well enough that the backwards-compatible portion (for
an undeclared identifier rather than a lookup that finds functions but
no function templates) is enabled in all language modes.
llvm-svn: 360308
Summary:
- For template arguments ending with `>>>`, we should cease lookahead
and treat it as type-id firstly, so that deduction could work
properly.
Reviewers: tra, yaxunl
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61396
llvm-svn: 360214
Keep looking for decl-specifiers after an unknown identifier. Don't
issue diagnostics about an error type specifier conflicting with later
type specifiers.
llvm-svn: 360117
The parser was dealing with unexpected "template" keywords after "using"
keywords too late and putting the parser into the wrong state, which could
lead to a crash down the line. This change allows the parser to consume the
bad "template" keywords earlier, and continue parsing as if "template" was
never there to begin with for better error recovery.
llvm-svn: 359740
Clang emits a warning when using a pure specifier =0 in a function definition
at class scope (a MS-specific construct), when using -fms-extensions.
However, to detect this, it was using FD->isCanonicalDecl() on function
declaration, which was also detecting out-of-class definition of member
functions of class templates. Fix this by using !FD->isOutOfLine() instead.
Fixes PR21334.
Differential Revision: https://reviews.llvm.org/D29707
Reviewed By: riccibruno
Reviewers: rnk, riccibruno
Patch By: Rudy Pons
llvm-svn: 358849
We want to make objc_nonlazy_class apply to implementations, but ran into this.
There doesn't seem to be any reason that this isn't supported.
Differential revision: https://reviews.llvm.org/D60542
llvm-svn: 358200
For backwards compatibility we allow alternative spelling of address
spaces - 'private', 'local', 'global', 'constant', 'generic'.
In order to accept 'private' correctly, parsing has been changed to
understand different use cases - access specifier vs address space.
Fixes PR40707 and PR41011!
Differential Revision: https://reviews.llvm.org/D59603
llvm-svn: 356888
This adds support for static_assert() (and _Static_assert()) in
@interface/@implementation ivar lists and in @interface method declarations.
It was already supported in @implementation blocks outside of the ivar lists.
The assert AST nodes are added at file scope, matching where other
(non-Objective-C) declarations at @interface / @implementation level go (cf
`allTUVariables`).
Also add a `__has_feature(objc_c_static_assert)` that's true in C11 (and
`__has_extension(objc_c_static_assert)` that's always true) and
`__has_feature(objc_cxx_static_assert)` that's true in C++11 modea fter this
patch, so it's possible to check if this is supported.
Differential Revision: https://reviews.llvm.org/D59223
llvm-svn: 356148
Previously, we parsed it only in the top level, which excludes namespaces and
extern "C" blocks.
rdar://problem/48818890
Differential revision: https://reviews.llvm.org/D59282
llvm-svn: 356075
This patch adds #pragma clang loop pipeline and #pragma clang loop pipeline_initiation_interval for debugging or reducing compile time purposes. It is possible to disable SWP for concrete loops to save compilation time or to find bugs by not doing SWP to certain loops. It is possible to set value of initiation interval to concrete number to save compilation time by not doing extra pipeliner passes or to check created schedule for specific initiation interval.
Patch by Alexey Lapshin.
llvm-svn: 350414
Rather than sprinkle calls to DiagnoseUnusedExprResult() around in places where we want diagnostics, we now diagnose unused expression statements and full expressions in a more generic way when acting on the final expression statement. This results in more appropriate diagnostics for [[nodiscard]] where we were previously lacking them, such as when the body of a for loop is not a compound statement.
This patch fixes PR39837.
llvm-svn: 350404
Namespaces are introduced by adding an "identifier." before a
push/pop directive. Pop directives with namespaces can only pop a
attribute group that was pushed with the same namespace. Push and pop
directives that don't opt into namespaces have the same semantics.
This is necessary to prevent a pitfall of using multiple #pragma
clang attribute directives spread out in a large file, particularly
when macros are involved. It isn't easy to see which pop corripsonds
to which push, so its easy to inadvertently pop the wrong group.
Differential revision: https://reviews.llvm.org/D55628
llvm-svn: 349845
This moves everything primarily testing the functionality of -ast-dump and -ast-print into their own directory, rather than leaving the tests spread around the testing directory.
llvm-svn: 348017
Only push the outermost record as a DeclContext when parsing a function
body. See the comments in Sema::getContainingDC about the way the parser
pushes contexts. This is intended to match the behavior the parser
normally displays where it parses all method bodies from all nested
classes at the end of the outermost class, when all nested classes are
complete.
Fixes PR38460.
llvm-svn: 347627
Summary:
clang has `-Wextra-semi` (D43162), which is not dictated by the currently selected standard.
While that is great, there is at least one more source of need-less semis - 'null statements'.
Sometimes, they are needed:
```
for(int x = 0; continueToDoWork(x); x++)
; // Ugly code, but the semi is needed here.
```
But sometimes they are just there for no reason:
```
switch(X) {
case 0:
return -2345;
case 5:
return 0;
default:
return 42;
}; // <- oops
;;;;;;;;;;; <- OOOOPS, still not diagnosed. Clearly this is junk.
```
Additionally:
```
if(; // <- empty init-statement
true)
;
switch (; // empty init-statement
x) {
...
}
for (; // <- empty init-statement
int y : S())
;
}
As usual, things may or may not go sideways in the presence of macros.
While evaluating this diag on my codebase of interest, it was unsurprisingly
discovered that Google Test macros are *very* prone to this.
And it seems many issues are deep within the GTest itself, not
in the snippets passed from the codebase that uses GTest.
So after some thought, i decided not do issue a diagnostic if the semi
is within *any* macro, be it either from the normal header, or system header.
Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=39111 | PR39111 ]]
Reviewers: rsmith, aaron.ballman, efriedma
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D52695
llvm-svn: 347339
Richard Smith