Commit Graph

2787 Commits

Author SHA1 Message Date
Richard Trieu 637af4cc37 Add -Wbitwise-conditional-parentheses to warn on mixing '|' and '&' with "?:"
Extend -Wparentheses to cover mixing bitwise-and and bitwise-or with the
conditional operator. There's two main cases seen with this:

unsigned bits1 = 0xf0 | cond ? 0x4 : 0x1;
unsigned bits2 = cond1 ? 0xf0 : 0x10 | cond2 ? 0x5 : 0x2;

// Intended order of evaluation:
unsigned bits1 = 0xf0 | (cond ? 0x4 : 0x1);
unsigned bits2 = (cond1 ? 0xf0 : 0x10) | (cond2 ? 0x5 : 0x2);

// Actual order of evaluation:
unsigned bits1 = (0xf0 | cond) ? 0x4 : 0x1;
unsigned bits2 = cond1 ? 0xf0 : ((0x10 | cond2) ? 0x5 : 0x2);

Differential Revision: https://reviews.llvm.org/D66043

llvm-svn: 375326
2019-10-19 01:47:49 +00:00
Richard Smith 974c8b7e2f [c++20] Add rewriting from comparison operators to <=> / ==.
This adds support for rewriting <, >, <=, and >= to a normal or reversed
call to operator<=>, for rewriting != to a normal or reversed call to
operator==, and for rewriting <=> and == to reversed forms of those same
operators.

Note that this is a breaking change for various C++17 code patterns,
including some in use in LLVM. The most common patterns (where an
operator== becomes ambiguous with a reversed form of itself) are still
accepted under this patch, as an extension (with a warning). I'm hopeful
that we can get the language rules fixed before C++20 ships, and the
extension warning is aimed primarily at providing data to inform that
decision.

llvm-svn: 375306
2019-10-19 00:04:43 +00:00
James Y Knight ccc4d83cda [ObjC] Diagnose implicit type coercion from ObjC 'Class' to object
pointer types.

For example, in Objective-C mode, the initialization of 'x' in:
```
  @implementation MyType
  + (void)someClassMethod {
    MyType *x = self;
  }
  @end
```
is correctly diagnosed with an incompatible-pointer-types warning, but
in Objective-C++ mode, it is not diagnosed at all -- even though
incompatible pointer conversions generally become an error in C++.

This patch fixes that oversight, allowing implicit conversions
involving Class only to/from unqualified-id, and between qualified and
unqualified Class, where the protocols are compatible.

Note that this does change some behaviors in Objective-C, as well, as
shown by the modified tests.

Of particular note is that assignment from from 'Class<MyProtocol>' to
'id<MyProtocol>' now warns. (Despite appearances, those are not
compatible types. 'Class<MyProtocol>' is not expected to have instance
methods defined by 'MyProtocol', while 'id<MyProtocol>' is.)

Differential Revision: https://reviews.llvm.org/D67983

llvm-svn: 375125
2019-10-17 15:27:04 +00:00
Richard Smith 7e8fe67f0e PR43080: Do not build context-sensitive expressions during name classification.
Summary:
We don't know what context to use until the classification result is
consumed by the parser, which could happen in a different semantic
context. So don't build the expression that results from name
classification until we get to that point and can handle it properly.

This covers everything except C++ implicit class member access, which
is a little awkward to handle properly in the face of the protected
member access check. But it at least fixes all the currently-filed
instances of PR43080.

Reviewers: efriedma

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68896

llvm-svn: 374826
2019-10-14 21:53:03 +00:00
Alexey Bataev 0e100037d7 [OPENMP]Fix codegen for private variably length vars in combined
constructs.

If OpenMP construct includes several capturing regions and the variable
is declared as private, the length of the inner variable length array is
not captured in outer captured regions, only in the innermost region.
Patch fixes this bug.

llvm-svn: 374787
2019-10-14 16:44:01 +00:00
Michael Liao e398def943 [sema] Revise `getCurrentMangleNumberContext` interface. NFC.
- Prefer returning mulitple values using a tuple instead of
  additional pointers/references.

llvm-svn: 374274
2019-10-10 03:14:51 +00:00
Richard Smith 4a6861a7e5 [c++20] P1152R4: warn on any simple-assignment to a volatile lvalue
whose value is not ignored.

We don't warn on all the cases that are deprecated: specifically, we
choose to not warn for now if there are parentheses around the
assignment but its value is not actually used. This seems like a more
defensible rule, particularly for cases like sizeof(v = a), where the
parens are part of the operand rather than the sizeof syntax.

llvm-svn: 374135
2019-10-09 02:04:54 +00:00
Richard Smith 84ef9c6493 [c++20] Implement most of P1152R4.
Diagnose some now-deprecated uses of volatile types:
 * as function parameter types and return types
 * as the type of a structured binding declaration
 * as the type of the lvalue operand of an increment / decrement /
   compound assignment operator

This does not implement a check for the deprecation of simple
assignments whose results are used; that check requires somewhat
more complexity and will be addressed separately.

llvm-svn: 374133
2019-10-09 00:49:40 +00:00
James Clarke 67f542aba7 [Diagnostics] Silence -Wsizeof-array-div for character buffers
Summary:
Character buffers are sometimes used to represent a pool of memory that
contains non-character objects, due to them being synonymous with a stream of
bytes on almost all modern architectures. Often, when interacting with hardware
devices, byte buffers are therefore used as an intermediary and so we can end
Character buffers are sometimes used to represent a pool of memory that
contains non-character objects, due to them being synonymous with a stream of
bytes on almost all modern architectures. Often, when interacting with hardware
devices, byte buffers are therefore used as an intermediary and so we can end
up generating lots of false-positives.

Moreover, due to the ability of character pointers to alias non-character
pointers, the strict aliasing violations that would generally be implied by the
calculations caught by the warning (if the calculation itself is in fact
correct) do not apply here, and so although the length calculation may be
wrong, that is the only possible issue.

Reviewers: rsmith, xbolva00, thakis

Reviewed By: xbolva00, thakis

Subscribers: thakis, lebedev.ri, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68526

llvm-svn: 374035
2019-10-08 11:34:02 +00:00
David Bolvansky aaea76ba02 [Diagnostics] Emit better -Wbool-operation's warning message if we known that the result is always true
llvm-svn: 373973
2019-10-07 21:57:03 +00:00
David Bolvansky 83b81c1f6e [Diagnostics] Highlight expr's source range for -Wbool-operation
Warning message looks better; and GCC adds it too.

llvm-svn: 373828
2019-10-05 13:28:15 +00:00
David Bolvansky 559265c8da [Diagnostics] Use Expr::isKnownToHaveBooleanValue() to check bitwise negation of bool in languages without a bool type
Thanks for this advice, Richard Trieu!

llvm-svn: 373817
2019-10-05 08:02:11 +00:00
Richard Smith 772e266fbf Properly handle instantiation-dependent array bounds.
We previously failed to treat an array with an instantiation-dependent
but not value-dependent bound as being an instantiation-dependent type.
We now track the array bound expression as part of a constant array type
if it's an instantiation-dependent expression.

llvm-svn: 373685
2019-10-04 01:25:59 +00:00
David Bolvansky b4ee523ffc [Diagnostics] Bitwise negation of a boolean expr always evaluates to true; warn with -Wbool-operation
Requested here:
http://lists.llvm.org/pipermail/cfe-dev/2019-October/063452.html

llvm-svn: 373614
2019-10-03 15:17:59 +00:00
John McCall 36b12a861c Rename TypeNodes.def to TypeNodes.inc for consistency across all
our autogenerated files.  NFC.

As requested by Nico Weber.

llvm-svn: 373425
2019-10-02 06:35:23 +00:00
Simon Pilgrim 6891c72d0f SemaExpr - silence static analyzer getAs<> null dereference warnings. NFCI.
The static analyzer is warning about potential null dereferences, but in these cases we should be able to use castAs<> directly and if not assert will fire for us.

llvm-svn: 373150
2019-09-28 14:01:52 +00:00
Michael Liao 24337db616 [CUDA][HIP] Enable kernel function return type deduction.
Summary:
- Even though only `void` is still accepted as the deduced return type,
  enabling deduction/instantiation on the return type allows more
  consistent coding.

Reviewers: tra, jlebar

Subscribers: cfe-commits, yaxunl

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68031

llvm-svn: 372898
2019-09-25 16:51:45 +00:00
David Bolvansky 28b38c277a [Diagnostics] Warn for enum constants in bool context (-Wint-in-bool-context; GCC compatibility)
Extracted from D63082.

llvm-svn: 372664
2019-09-23 22:09:49 +00:00
David Bolvansky 116e6cf36e [Diagnostics] Avoid -Wsizeof-array-div when dividing the size of a nested array by the size of the deepest base type
llvm-svn: 372600
2019-09-23 12:54:35 +00:00
James Y Knight c2ca003baf NFC: Change ObjCQualified*TypesAreCompatible to take
ObjCObjectPointerType arguments.

All callers already had one, just creating a QualType to pass, after
which the function cast it right back.

llvm-svn: 372492
2019-09-21 22:31:28 +00:00
Richard Trieu 4c05de8c1d Merge and improve code that detects same value in comparisons.
-Wtautological-overlap-compare and self-comparison from -Wtautological-compare
relay on detecting the same operand in different locations.  Previously, each
warning had it's own operand checker.  Now, both are merged together into
one function that each can call.  The function also now looks through member
access and array accesses.

Differential Revision: https://reviews.llvm.org/D66045

llvm-svn: 372453
2019-09-21 03:02:26 +00:00
Alexey Bataev bf5d429094 [OPENMP5.0]Introduce attribute for declare variant directive.
Added attribute for declare variant directive. It will allow to handle
declare variant directive at the codegen and will allow to add extra
checks.

llvm-svn: 372147
2019-09-17 17:36:49 +00:00
David Bolvansky b8185153f3 [Diagnostics] Added silence note for -Wsizeof-array-div; suggest extra parens
llvm-svn: 371924
2019-09-14 19:38:55 +00:00
Richard Smith c624510f13 For PR17164: split -fno-lax-vector-conversion into three different
levels:

 -- none: no lax vector conversions [new GCC default]
 -- integer: only conversions between integer vectors [old GCC default]
 -- all: all conversions between same-size vectors [Clang default]

For now, Clang still defaults to "all" mode, but per my proposal on
cfe-dev (2019-04-10) the default will be changed to "integer" as soon as
that doesn't break lots of testcases. (Eventually I'd like to change the
default to "none" to match GCC and general sanity.)

Following GCC's behavior, the driver flag -flax-vector-conversions is
translated to -flax-vector-conversions=integer.

This reinstates r371805, reverted in r371813, with an additional fix for
lldb.

llvm-svn: 371817
2019-09-13 06:02:15 +00:00
Jonas Devlieghere 4aaa77e48d Revert "For PR17164: split -fno-lax-vector-conversion into three different"
This breaks the LLDB build. I tried reaching out to Richard, but haven't
gotten a reply yet.

llvm-svn: 371813
2019-09-13 05:16:59 +00:00
Richard Smith 49c4e58b75 For PR17164: split -fno-lax-vector-conversion into three different
levels:

 -- none: no lax vector conversions [new GCC default]
 -- integer: only conversions between integer vectors [old GCC default]
 -- all: all conversions between same-size vectors [Clang default]

For now, Clang still defaults to "all" mode, but per my proposal on
cfe-dev (2019-04-10) the default will be changed to "integer" as soon as
that doesn't break lots of testcases. (Eventually I'd like to change the
default to "none" to match GCC and general sanity.)

Following GCC's behavior, the driver flag -flax-vector-conversions is
translated to -flax-vector-conversions=integer.

llvm-svn: 371805
2019-09-13 02:20:00 +00:00
David Bolvansky 3240ad4ced [Diagnostics] Add -Wsizeof-array-div
Summary: Clang version of https://www.viva64.com/en/examples/v706/

Reviewers: rsmith

Differential Revision: https://reviews.llvm.org/D67287

llvm-svn: 371605
2019-09-11 10:59:47 +00:00
Richard Smith 245ba2c25f PR43242: Fix crash when typo-correcting to an operator() that should not
have been visible.

llvm-svn: 371468
2019-09-09 23:07:22 +00:00
Akira Hatanaka 3f2c9917a4 [Sema][ObjC] Mark C union fields that have non-trivial ObjC ownership
qualifications as unavailable if the union is declared in a system
header

r365985 stopped marking those fields as unavailable, which caused the
union's NonTrivialToPrimitive* bits to be set to true. This patch
restores the behavior prior to r365985, except that users can explicitly
specify the ownership qualification of the field to instruct the
compiler not to mark it as unavailable.

rdar://problem/53420753

Differential Revision: https://reviews.llvm.org/D65256

llvm-svn: 371276
2019-09-07 00:34:47 +00:00
Akira Hatanaka 090510608d [Sema] Diagnose default-initialization, destruction, and copying of
non-trivial C union types

This recommits r365985, which was reverted because it broke a few
projects using unions containing non-trivial ObjC pointer fields in
system headers. We now have a patch to fix the problem (see
https://reviews.llvm.org/D65256).

Original commit message:

This patch diagnoses uses of non-trivial C unions and structs/unions
containing non-trivial C unions in the following contexts, which require
default-initialization, destruction, or copying of the union objects,
instead of disallowing fields of non-trivial types in C unions, which is
what we currently do:

- function parameters.
- function returns.
- assignments.
- compound literals.
- block captures except capturing of `__block` variables by non-escaping blocks.
- local and global variable definitions.
- lvalue-to-rvalue conversions of volatile types.

See the discussion in https://reviews.llvm.org/D62988 for more background.

rdar://problem/50679094

Differential Revision: https://reviews.llvm.org/D63753

llvm-svn: 371275
2019-09-07 00:34:43 +00:00
David Bolvansky 454e40eaf3 [NFCI] Unbreak buildbots
llvm-svn: 371226
2019-09-06 16:30:44 +00:00
David Bolvansky fd07568074 [Diagnostics] Refactor code for -Wsizeof-pointer-div, catch more cases; also add -Wsizeof-array-div
Previously, -Wsizeof-pointer-div failed to catch:
const int *r;
sizeof(r) / sizeof(int);

Now fixed.
Also introduced -Wsizeof-array-div which catches bugs like:
sizeof(r) / sizeof(short);

(Array element type does not match type of sizeof operand).

llvm-svn: 371222
2019-09-06 16:12:48 +00:00
David Bolvansky 872108bea5 [Diagnostics] Minor improvements for -Wxor-used-as-pow
Extracted from D66397; implemented suggestion for 2^64; tests revisited.

llvm-svn: 371122
2019-09-05 20:50:48 +00:00
Richard Smith 5030928d60 [c++20] Implement semantic restrictions for C++20 designated
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
2019-08-30 22:52:55 +00:00
Richard Smith 26a92d5852 Improve behavior in the case of stack exhaustion.
Summary:
Clang performs various recursive operations (such as template instantiation),
and may use non-trivial amounts of stack space in each recursive step (for
instance, due to recursive AST walks). While we try to keep the stack space
used by such steps to a minimum and we have explicit limits on the number of
such steps we perform, it's impractical to guarantee that we won't blow out the
stack on deeply recursive template instantiations on complex ASTs, even with
only a moderately high instantiation depth limit.

The user experience in these cases is generally terrible: we crash with
no hint of what went wrong. Under this patch, we attempt to do better:

 * Detect when the stack is nearly exhausted, and produce a warning with a
   nice template instantiation backtrace, telling the user that we might
   run slowly or crash.

 * For cases where we're forced to trigger recursive template
   instantiation in arbitrarily-deeply-nested contexts, check whether
   we're nearly out of stack space and allocate a new stack (by spawning
   a new thread) after producing the warning.

Reviewers: rnk, aaron.ballman

Subscribers: mgorny, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66361

llvm-svn: 369940
2019-08-26 18:18:07 +00:00
Alexey Bataev 729e242a79 [OPENMP5.0]Add support for device_type clause in declare target
construct.

OpenMP 5.0 introduced new clause for declare target directive, device_type clause, which may accept values host, nohost, and any. Host means
that the function must be emitted only for the host, nohost - only for
the device, and any - for both, device and the host.

llvm-svn: 369775
2019-08-23 16:11:14 +00:00
Joel E. Denny 7d5bc55433 [OpenMP] Permit map with DSA on combined directive
For `map`, the following restriction changed in OpenMP 5.0:

* OpenMP 4.5 [2.15.5.1, Restrictions]: "A list item cannot appear in
  both a map clause and a data-sharing attribute clause on the same
  construct.

* OpenMP 5.0 [2.19.7.1, Restrictions]: "A list item cannot appear in
  both a map clause and a data-sharing attribute clause on the same
  construct unless the construct is a combined construct."

This patch removes this restriction in the case of combined constructs
and OpenMP 5.0, and it updates Sema not to capture a scalar by copy in
the target region when `firstprivate` and `map` appear for that scalar
on a combined target construct.

This patch also adds a fixme to a test that now reveals that a
diagnostic about loop iteration variables is dropped in the case of
OpenMP 5.0.  That bug exists regardless of this patch's changes.

Reviewed By: ABataev, jdoerfert, hfinkel, kkwli0

Differential Revision: https://reviews.llvm.org/D65835

llvm-svn: 369619
2019-08-22 03:34:30 +00:00
David Bolvansky 920890e268 [Diagnostics] Diagnose misused xor as pow
Summary:
Motivation:
https://twitter.com/jfbastien/status/1139298419988549632
https://twitter.com/mikemx7f/status/1139335901790625793
https://codesearch.isocpp.org/cgi-bin/cgi_ppsearch?q=10+%5E&search=Search

Reviewers: jfb, rsmith, regehr, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: lebedev.ri, Quuxplusone, erik.pilkington, riccibruno, dexonsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63423

llvm-svn: 369217
2019-08-18 19:14:14 +00:00
David Bolvansky b4806822d2 [Diagnostics] Improve -Wsizeof-pointer-div
Emit diag note with a location of pointer declaration.
Revisited/added tests.

llvm-svn: 369206
2019-08-18 10:10:09 +00:00
Jonas Devlieghere 2b3d49b610 [Clang] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

Differential revision: https://reviews.llvm.org/D66259

llvm-svn: 368942
2019-08-14 23:04:18 +00:00
Richard Sandiford eb485fbc71 Add SVE opaque built-in types
This patch adds the SVE built-in types defined by the Procedure Call
Standard for the Arm Architecture:

   https://developer.arm.com/docs/100986/0000

It handles the types in all relevant places that deal with built-in types.
At the moment, some of these places bail out with an error, including:

   (1) trying to generate LLVM IR for the types
   (2) trying to generate debug info for the types
   (3) trying to mangle the types using the Microsoft C++ ABI
   (4) trying to @encode the types in Objective C

(1) and (2) are fixed by follow-on patches but (unlike this patch)
they deal mostly with target-specific LLVM details, so seemed like
a logically separate change.  There is currently no spec for (3) and
(4), so reporting an error seems like the correct behaviour for now.

The intention is that the types will become sizeless types:

   http://lists.llvm.org/pipermail/cfe-dev/2019-June/062523.html

The main purpose of the sizeless type extension is to diagnose
impossible or dangerous uses of the types, such as any that would
require sizeof to have a meaningful defined value.

Until then, the patch sets the alignments of the types to the values
specified in the link above.  It also sets the sizes of the types to
zero, which is chosen to be consistently wrong and shouldn't affect
correctly-written code (i.e. code that would compile even with the
sizeless type extension).

The patch adds the common subset of functionality needed to test the
sizeless type extension on the one hand and to provide SVE intrinsic
functions on the other.  After this patch, the two pieces of work are
essentially independent.

The patch is based on one by Graham Hunter:

   https://reviews.llvm.org/D59245

Differential Revision: https://reviews.llvm.org/D62960

llvm-svn: 368413
2019-08-09 08:52:54 +00:00
Richard Trieu 07e6798baf Inline diagnostic text into .td file. NFC.
llvm-svn: 368244
2019-08-08 01:45:31 +00:00
George Burgess IV f708f0a243 [Sema] Add -Wpointer-compare
This patch adds a warning that diagnoses comparisons of pointers to
'\0'. This is often indicative of a bug (e.g. the user might've
forgotten to dereference the pointer).

Patch by Elaina Guan!

Differential Revision: https://reviews.llvm.org/D65595

llvm-svn: 367940
2019-08-05 22:15:40 +00:00
Akira Hatanaka 6f6156b9fc Revert "[Sema] Diagnose default-initialization, destruction, and copying of"
This reverts commit r365985.

Prior to r365985, clang used to mark C union fields that have
non-trivial ObjC ownership qualifiers as unavailable if the union was
declared in a system header. r365985 stopped doing so, which caused the
swift compiler to crash when it tried to import a non-trivial union.

I have a patch that fixes the crash (https://reviews.llvm.org/D65256),
but I'm temporarily reverting the original patch until we can decide on
whether it's taking the right approach.

llvm-svn: 367076
2019-07-26 00:02:17 +00:00
JF Bastien dbc0a5df8d Allow prefetching from non-zero address spaces
Summary:
This is useful for targets which have prefetch instructions for non-default address spaces.

<rdar://problem/42662136>

Subscribers: nemanjai, javed.absar, hiraditya, kbarton, jkorous, dexonsmith, cfe-commits, llvm-commits, RKSimon, hfinkel, t.p.northover, craig.topper, anemet

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D65254

llvm-svn: 367032
2019-07-25 16:11:57 +00:00
Richard Smith 6a38205039 [c++20] P1161R3: a[b,c] is deprecated.
llvm-svn: 366630
2019-07-20 09:32:27 +00:00
Rui Ueyama 49a3ad21d6 Fix parameter name comments using clang-tidy. NFC.
This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
2019-07-16 04:46:31 +00:00
Akira Hatanaka 81b03d4a08 [Sema] Diagnose default-initialization, destruction, and copying of
non-trivial C union types

This patch diagnoses uses of non-trivial C unions and structs/unions
containing non-trivial C unions in the following contexts, which require
default-initialization, destruction, or copying of the union objects,
instead of disallowing fields of non-trivial types in C unions, which is
what we currently do:

- function parameters.
- function returns.
- assignments.
- compound literals.
- block captures except capturing of `__block` variables by non-escaping
  blocks.
- local and global variable definitions.
- lvalue-to-rvalue conversions of volatile types.

See the discussion in https://reviews.llvm.org/D62988 for more background.

rdar://problem/50679094

Differential Revision: https://reviews.llvm.org/D63753

llvm-svn: 365985
2019-07-13 01:47:15 +00:00
Marco Antognini b00d5f732c [OpenCL][Sema] Fix builtin rewriting
This patch ensures built-in functions are rewritten using the proper
parent declaration.

Existing tests are modified to run in C++ mode to ensure the
functionality works also with C++ for OpenCL while not increasing the
testing runtime.

llvm-svn: 365499
2019-07-09 15:04:23 +00:00
Aaron Ballman b1e511bf5a Ignore trailing NullStmts in StmtExprs for GCC compatibility.
Ignore trailing NullStmts in compound expressions when determining the result type and value. This is to match the GCC behavior which ignores semicolons at the end of compound expressions.

Patch by Dominic Ferreira.

llvm-svn: 365498
2019-07-09 15:02:07 +00:00
Reid Kleckner 345708b681 Revert [Sema] Resolve placeholder types before type deduction to silence spurious `-Warc-repeated-use-of-weak` warnings
This reverts r365382 (git commit 8b1becf2e3)

Appears to regress this semi-reduced fragment of valid code from windows
SDK headers:

  #define InterlockedIncrement64 _InterlockedIncrement64
  extern "C" __int64 InterlockedIncrement64(__int64 volatile *Addend);
  #pragma intrinsic(_InterlockedIncrement64)
  unsigned __int64 InterlockedIncrement(unsigned __int64 volatile *Addend) {
    return (unsigned __int64)(InterlockedIncrement64)((volatile __int64 *)Addend);
  }

Found on a buildbot here, but no mail was sent due to it already being
red:
http://lab.llvm.org:8011/builders/sanitizer-windows/builds/48067

llvm-svn: 365393
2019-07-08 21:59:07 +00:00
Akira Hatanaka 8b1becf2e3 [Sema] Resolve placeholder types before type deduction to silence
spurious `-Warc-repeated-use-of-weak` warnings

The spurious -Warc-repeated-use-of-weak warnings are issued when an
initializer expression uses a weak ObjC pointer.

My first attempt to silence the warnings (r350917) caused clang to
reject code that is legal in C++17. The patch is based on the feedback I
received from Richard when the patch was reverted.

http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190422/268945.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190422/268943.html

Differential Revision: https://reviews.llvm.org/D62645

llvm-svn: 365382
2019-07-08 20:04:39 +00:00
Alexey Bataev b600ae37a5 [OPENMP]Fix handling of lambda captures in target regions.
Previously, lambda captures were processed in the function called during
capturing the variables. It leads to the recursive functions calls and
may result in the compiler crash.

llvm-svn: 364820
2019-07-01 17:46:52 +00:00
Richard Smith 7939ba08ab [cxx2a] P1236R1: the validity of a left shift does not depend on the
value of the LHS operand.

llvm-svn: 364265
2019-06-25 01:45:26 +00:00
George Burgess IV 67d1f8ae6d clang-format a block; NFC
The indentation of the return here was off, and confusing as a result.
Cleaned up a bit extra while I was in the area.

llvm-svn: 364104
2019-06-21 20:49:47 +00:00
Alexey Bataev 0f21507b44 [OPENMP]Fix PR42068: Vla type is not captured.
If the variably modified type is declared outside of the captured region
and then used in the cast expression along with array subscript
expression, the type is not captured and it leads to the compiler crash.

llvm-svn: 364080
2019-06-21 17:28:41 +00:00
Gauthier Harnisch dea9d57d95 [clang] Small improvments after Adding APValue to ConstantExpr
Summary:
this patch has multiple small improvements related to the APValue in ConstantExpr.

changes:
 - APValue in ConstantExpr are now cleaned up using ASTContext::addDestruction instead of there own system.
 - ConstantExprBits Stores the ValueKind of the result beaing stored.
 - VerifyIntegerConstantExpression now stores the evaluated value in ConstantExpr.
 - the Constant Evaluator uses the stored value of ConstantExpr when available.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63376

llvm-svn: 364011
2019-06-21 08:26:21 +00:00
Richard Smith 27252a1f95 PR23833, DR2140: an lvalue-to-rvalue conversion on a glvalue of type
nullptr_t does not access memory.

We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.

This reinstates r363337, reverted in r363352.

llvm-svn: 363429
2019-06-14 17:46:38 +00:00
Richard Smith 24cdcadcc5 C++ DR712 and others: handle non-odr-use resulting from an lvalue-to-rvalue conversion applied to a member access or similar not-quite-trivial lvalue expression.
Summary:
When a variable is named in a context where we can't directly emit a
reference to it (because we don't know for sure that it's going to be
defined, or it's from an enclosing function and not captured, or the
reference might not "work" for some reason), we emit a copy of the
variable as a global and use that for the known-to-be-read-only access.

This reinstates r363295, reverted in r363352, with a fix for PR42276:
we now produce a proper name for a non-odr-use reference to a static
constexpr data member. The name <mangled-name>.const is used in that
case; such names are reserved to the implementation for cases such as
this and should demangle nicely.

Reviewers: rjmccall

Subscribers: jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63157

llvm-svn: 363428
2019-06-14 17:46:37 +00:00
Gauthier Harnisch 796ed03b84 [C++20] add Basic consteval specifier
Summary:
this revision adds Lexing, Parsing and Basic Semantic for the consteval specifier as specified by http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1073r3.html

with this patch, the consteval specifier is treated as constexpr but can only be applied to function declaration.

Changes:
 - add the consteval keyword.
 - add parsing of consteval specifier for normal declarations and lambdas expressions.
 - add the whether a declaration is constexpr is now represented by and enum everywhere except for variable because they can't be consteval.
 - adapt diagnostic about constexpr to print constexpr or consteval depending on the case.
 - add tests for basic semantic.

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: eraman, efriedma, rnkovacs, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61790

llvm-svn: 363362
2019-06-14 08:56:20 +00:00
Nico Weber 3d02b895ed Revert 363295, it caused PR42276. Also revert follow-ups 363337, 363340.
Revert 363340 "Remove unused SK_LValueToRValue initialization step."
Revert 363337 "PR23833, DR2140: an lvalue-to-rvalue conversion on a glvalue of type"
Revert 363295 "C++ DR712 and others: handle non-odr-use resulting from an lvalue-to-rvalue conversion applied to a member access or similar not-quite-trivial lvalue expression."

llvm-svn: 363352
2019-06-14 04:05:17 +00:00
Richard Smith 0476d069e3 PR23833, DR2140: an lvalue-to-rvalue conversion on a glvalue of type
nullptr_t does not access memory.

We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.

This reinstates r345562, reverted in r346065, now that CodeGen's
handling of non-odr-used variables has been fixed.

llvm-svn: 363337
2019-06-13 23:31:04 +00:00
Richard Smith 17965d42f4 C++ DR712 and others: handle non-odr-use resulting from an lvalue-to-rvalue conversion applied to a member access or similar not-quite-trivial lvalue expression.
Summary:
When a variable is named in a context where we can't directly emit a
reference to it (because we don't know for sure that it's going to be
defined, or it's from an enclosing function and not captured, or the
reference might not "work" for some reason), we emit a copy of the
variable as a global and use that for the known-to-be-read-only access.

Reviewers: rjmccall

Subscribers: jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63157

llvm-svn: 363295
2019-06-13 19:00:16 +00:00
Richard Smith 7f61d44178 Mark declarations as referenced by a default argument in a
potentially-evaluated context.

This applies even if the use of the default argument is within an
unevaluated context.

llvm-svn: 363113
2019-06-11 23:51:46 +00:00
Richard Smith 1bbad59379 For DR712: store on a MemberExpr whether it constitutes an odr-use.
llvm-svn: 363087
2019-06-11 17:50:36 +00:00
Richard Smith 715f7a1bd0 For DR712: store on a DeclRefExpr whether it constitutes an odr-use.
Begin restructuring to support the forms of non-odr-use reference
permitted by DR712.

llvm-svn: 363086
2019-06-11 17:50:32 +00:00
Reid Kleckner e78333a010 Require stdcall etc parameters to be complete on ODR use
Functions using stdcall, fastcall, or vectorcall with C linkage mangle
in the size of the parameter pack. Calculating the size of the pack
requires the parameter types to complete, which may require template
instantiation.

Previously, we would crash during IRgen when requesting the size of
incomplete or uninstantiated types, as in this reduced example:
  struct Foo;
  void __fastcall bar(struct Foo o);
  void (__fastcall *fp)(struct Foo) = &bar;

Reported in Chromium here: https://crbug.com/971245

Differential Revision: https://reviews.llvm.org/D62975

llvm-svn: 363000
2019-06-10 22:53:12 +00:00
Richard Smith 7dcd73340b Factor out repeated code to build a DeclRefExpr and mark it referenced.
llvm-svn: 362537
2019-06-04 18:30:46 +00:00
Richard Smith 7bf8f6fa8a PR42104: Support instantiations of lambdas that implicitly capture
packs.

Two changes:
 * Track odr-use via FunctionParmPackExprs to properly handle dependent
   odr-uses of packs in generic lambdas.
 * Do not instantiate implicit captures; instead, regenerate them by
   instantiating the body of the lambda. This is necessary to
   distinguish between cases where only one element of a pack is
   captured and cases where the entire pack is captured.

This reinstates r362358 (reverted in r362375) with a fix for an
uninitialized variable use in UpdateMarkingForLValueToRValue.

llvm-svn: 362531
2019-06-04 17:17:20 +00:00
Simon Pilgrim c716e5d6de Revert rL362358 : PR42104: Support instantiations of lambdas that implicitly capture packs.
Two changes:
 * Track odr-use via FunctionParmPackExprs to properly handle dependent
   odr-uses of packs in generic lambdas.
 * Do not instantiate implicit captures; instead, regenerate them by
   instantiating the body of the lambda. This is necessary to
   distinguish between cases where only one element of a pack is
   captured and cases where the entire pack is captured.
........
Fixes http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win buildbot failures

llvm-svn: 362375
2019-06-03 09:56:09 +00:00
Richard Smith ea0c66be55 PR42104: Support instantiations of lambdas that implicitly capture
packs.

Two changes:
 * Track odr-use via FunctionParmPackExprs to properly handle dependent
   odr-uses of packs in generic lambdas.
 * Do not instantiate implicit captures; instead, regenerate them by
   instantiating the body of the lambda. This is necessary to
   distinguish between cases where only one element of a pack is
   captured and cases where the entire pack is captured.

llvm-svn: 362358
2019-06-03 06:02:10 +00:00
Richard Smith 87346a15db Transform lambda expression captures when transforming an expression to
potentially-evaluated.

This ensures that every potentially-evaluated expression is built in a
potentially-evaluated context. No functionality change intended.

llvm-svn: 362336
2019-06-02 18:53:44 +00:00
Richard Smith 0621a8f353 Defer capture initialization for captured regions until after we've left
the captured region scope.

This removes a case where we would build expressions (and mark
declarations odr-used) in the wrong scope.

Remove the now-unused 'capture initializer' field on sema::Capture
(except for 'this' captures, which still need to be cleaned up).

No functionality change intended (except that we now very slightly more
precisely determine whether we need to use a capture or not when another
captured region encloses an OpenMP captured region).

llvm-svn: 362179
2019-05-31 00:45:10 +00:00
Richard Smith 2fdd95c1c8 Defer capture initialization for blocks until after we've left the
function scope.

This removes one of the last few cases where we build expressions in the
wrong function scope context. No functionality change intended.

llvm-svn: 362178
2019-05-31 00:45:09 +00:00
Sven van Haastregt ce127bb60e [OpenCL] Support logical vector operators in C++ mode
Support logical operators on vectors in C++ for OpenCL mode, to
preserve backwards compatibility with OpenCL C.

Differential Revision: https://reviews.llvm.org/D62588

llvm-svn: 362087
2019-05-30 12:35:19 +00:00
Richard Smith 30116531b8 Defer creating fields for captures until we finish building the
capturing expression or statement.

No functionality change yet. The intent is that we will also delay
building the initialization expression until the enclosing context, so
that:
a) we build the initialization expression in the right context, and
b) we can elide captures that are not odr-used, as suggested by P0588R1.

This also consolidates some duplicated code building capture fields into
a single place.

llvm-svn: 361893
2019-05-28 23:09:46 +00:00
Richard Smith 8cb63232d9 If capturing a variable fails, add a capture anyway (and mark it
invalid) so that we can avoid repeated diagnostics for the same capture.

llvm-svn: 361891
2019-05-28 23:09:44 +00:00
Richard Smith 94ef686f57 Move code to mark a variable as odr-used adjacement to all the related
code.

No functional change intended.

llvm-svn: 361890
2019-05-28 23:09:42 +00:00
Richard Smith 0353e5a6cd Permit static local structured bindings to be named from arbitrary scopes inside their declaring scope.
llvm-svn: 361686
2019-05-25 01:04:17 +00:00
Richard Smith de47d66191 Default arguments are potentially constant evaluated.
We need to eagerly instantiate constexpr functions used in them even if
the default argument is never actually used, because we might evaluate
portions of it when performing semantic checks.

llvm-svn: 361670
2019-05-24 21:08:12 +00:00
Richard Smith 5c3b1fd9ef Refactor use-marking to better match standard terminology. No
functionality change intended.

llvm-svn: 361668
2019-05-24 20:42:25 +00:00
Sven van Haastregt 50434e8df0 Enable queue_t and clk_event_t comparisons in C++ mode
Support queue_t and clk_event_t comparisons in C++ for OpenCL mode, to
preserve backwards compatibility with OpenCL C.

Differential Revision: https://reviews.llvm.org/D62208

llvm-svn: 361467
2019-05-23 09:20:08 +00:00
Eric Fiselier 708afb56c1 Implement __builtin_LINE() et. al. to support source location capture.
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
2019-05-16 21:04:15 +00:00
Alexey Bataev 41ebe0ce64 [OPENMP]Fix PR41768: check DSA for globals with default(none) clauses.
If the default(none) was specified for the construct, we might miss
diagnostic for the globals without explicitly specified data-sharing
attributes. Patch fixes this problem.

llvm-svn: 360362
2019-05-09 18:14:57 +00:00
Richard Smith b23c5e8c3d [c++20] Implement P0846R0: allow (ADL-only) calls to template-ids whose
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
2019-05-09 03:31:27 +00:00
Richard Smith 2194fb6ed9 When typo-correcting a function name, consider correcting to a type name
for a function-style cast.

llvm-svn: 360302
2019-05-09 00:57:24 +00:00
Anastasia Stulova 5b6dda33d1 [Sema][OpenCL] Make address space conversions a bit stricter.
The semantics for converting nested pointers between address
spaces are not very well defined. Some conversions which do not
really carry any meaning only produce warnings, and in some cases
warnings hide invalid conversions, such as 'global int*' to
'local float*'!

This patch changes the logic in checkPointerTypesForAssignment
and checkAddressSpaceCast to fail properly on implicit conversions
that should definitely not be permitted. We also dig deeper into the
pointer types and warn on explicit conversions where the address
space in a nested pointer changes, regardless of whether the address
space is compatible with the corresponding pointer nesting level
on the destination type.

Fixes PR39674!

Patch by ebevhan (Bevin Hansson)!

Differential Revision: https://reviews.llvm.org/D58236

llvm-svn: 360258
2019-05-08 14:23:49 +00:00
Richard Smith 255b85f03c Split ActOnCallExpr into an ActOnCallExpr to be called by the parser,
and a BuildCallExpr to be called internally within Sema to build /
rebuild calls.

llvm-svn: 360217
2019-05-08 01:36:36 +00:00
Leonard Chan c72aaf62d3 Recommit r359859 "[Attribute/Diagnostics] Print macro if definition is an attribute declaration"
Updated with fix for read of uninitialized memory.

llvm-svn: 360109
2019-05-07 03:20:17 +00:00
Richard Smith 7d02ca4878 Use DiagRuntimeBehavior for -Wunsequenced to weed out false positives
where either the modification or the other access is unreachable.

This reverts r359984 (which reverted r359962). The bug in clang-tidy's
test suite exposed by the original commit was fixed in r360009.

llvm-svn: 360010
2019-05-06 04:14:01 +00:00
Simon Pilgrim 4c3fbbf635 Revert rL359962 : Use DiagRuntimeBehavior for -Wunsequenced to weed out false positives
where either the modification or the other access is unreachable.
........
Try to fix buildbots

llvm-svn: 359984
2019-05-05 17:10:05 +00:00
Richard Smith 5dbfa76334 Use DiagRuntimeBehavior for -Wunsequenced to weed out false positives
where either the modification or the other access is unreachable.

llvm-svn: 359962
2019-05-04 05:20:14 +00:00
Richard Smith a6b41d7c52 CWG issue 727: Fix numerous bugs in support for class-scope explicit
specializations for variable templates.

llvm-svn: 359947
2019-05-03 23:51:38 +00:00
Leonard Chan ef2dc25a96 Revert "[Attribute/Diagnostics] Print macro if definition is an attribute declaration"
This reverts commit fc40cbd9d8.

llvm-svn: 359859
2019-05-03 03:28:06 +00:00
Leonard Chan fc40cbd9d8 [Attribute/Diagnostics] Print macro if definition is an attribute declaration
If an address_space attribute is defined in a macro, print the macro instead
when diagnosing a warning or error for incompatible pointers with different
address_spaces.

We allow this for all attributes (not just address_space), and for multiple
attributes declared in the same macro.

Differential Revision: https://reviews.llvm.org/D51329

llvm-svn: 359826
2019-05-02 20:38:14 +00:00
Richard Smith f19a8b0517 Replace ad-hoc tracking of pattern for an instantiated class-scope
explicit function specialization with the MemberSpecializationInfo used
everywhere else.

Not NFC: the ad-hoc pattern tracking was not being serialized /
deserialized properly. That's fixed here.

llvm-svn: 359747
2019-05-02 00:49:14 +00:00
Akira Hatanaka ac57af3284 [Sema][ObjC] Don't warn about an implicitly retained self if the
retaining block and all of the enclosing blocks are non-escaping.

If the block implicitly retaining self doesn't escape, there is no risk
of creating retain cycles, so clang shouldn't diagnose it and force
users to add self-> to silence the diagnostic.

Also, fix a bug where clang was failing to diagnose an implicitly
retained self inside a c++ lambda nested inside a block.

rdar://problem/25059955

Differential Revision: https://reviews.llvm.org/D60736

llvm-svn: 358624
2019-04-17 23:14:44 +00:00
Fangrui Song 75e74e077c Range-style std::find{,_if} -> llvm::find{,_if}. NFC
llvm-svn: 357359
2019-03-31 08:48:19 +00:00
Erik Pilkington 14f6d1527c [Sema] Fix an assert when a block captures a constexpr local
MarkVarDeclODRUsed indirectly calls captureInBlock, which creates a copy
expression. The copy expression is insulated in it's own
ExpressionEvaluationContext, so it saves, mutates, and restores MaybeODRUseExprs
as CleanupVarDeclMarking is iterating through it, leading to a crash. Fix this
by iterating through a local copy of MaybeODRUseExprs.

rdar://47493525

https://reviews.llvm.org/D59670

llvm-svn: 357040
2019-03-26 23:21:19 +00:00
Bruno Ricci 70ad396bc4 [Sema][NFCI] Don't allocate storage for the various CorrectionCandidateCallback unless we are going to do some typo correction
The various CorrectionCandidateCallbacks are currently heap-allocated
unconditionally. This was needed because of delayed typo correction.
However these allocations represent currently 15.4% of all allocations
(number of allocations) when parsing all of Boost (!), mostly because
of ParseCastExpression, ParseStatementOrDeclarationAfterAttrtibutes
and isCXXDeclarationSpecifier. Note that all of these callback objects
are small. Let's not do this.

Instead initially allocate the callback on the stack, and only do a
heap allocation if we are going to do some typo correction. Do this by:

1. Adding a clone function to each callback, which will do a polymorphic
   clone of the callback. This clone function is required to be implemented
   by every callback (of which there is a fair amount). Make sure this is
   the case by making it pure virtual.

2. Use this clone function when we are going to try to correct a typo.

This additionally cut the time of -fsyntax-only on all of Boost by 0.5%
(not that much, but still something). No functional changes intended.

Differential Revision: https://reviews.llvm.org/D58827

Reviewed By: rnk

llvm-svn: 356925
2019-03-25 17:08:51 +00:00