2973 Commits

Author SHA1 Message Date
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 8b1becf2e31d9170ee356a19c7b6ea991d3a520f)

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