Commit Graph

815 Commits

Author SHA1 Message Date
Mark de Wever 41fcd17250 [Sema] Avoid Wrange-loop-analysis false positives
When Wrange-loop-analysis issues a diagnostic on a dependent type in a
template the diagnostic may not be valid for all instantiations. Therefore
the diagnostic is suppressed during the instantiation. Non dependent types
still issue a diagnostic.

The same can happen when using macros. Therefore the diagnostic is
disabled for macros.

Fixes https://bugs.llvm.org/show_bug.cgi?id=44556

Differential Revision: https://reviews.llvm.org/D73007
2020-01-21 21:14:10 +01:00
Mark de Wever 9c74fb402e [Sema] Improve -Wrange-loop-analysis warnings.
No longer generate a diagnostic when a small trivially copyable type is
used without a reference. Before the test looked for a POD type and had no
size restriction. Since the range-based for loop is only available in
C++11 and POD types are trivially copyable in C++11 it's not required to
test for a POD type.

Since copying a large object will be expensive its size has been
restricted. 64 bytes is a common size of a cache line and if the object is
aligned the copy will be cheap. No performance impact testing has been
done.

Differential Revision: https://reviews.llvm.org/D72212
2020-01-11 15:34:02 +01:00
Mark de Wever e5ab1e49f9 Improve Wrange-loop-analyses for rvalue reference
The Wrange-loop-analyses warns if a copy is made. Suppress this warning when
a temporary is bound to a rvalue reference.

While fixing this issue also found a copy-paste error in test6, which is also
fixed.

Differential Revision: https://reviews.llvm.org/D71806
2020-01-01 20:02:18 +01:00
Mark de Wever f022a5a792 Adds fixit hints to the -Wrange-loop-analysis
Differential Revision: https://reviews.llvm.org/D68913
2020-01-01 20:02:00 +01:00
Tyker b0561b3346 [NFC] Refactor representation of materialized temporaries
Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: thakis, sammccall, ilya-biryukov, rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360
2019-11-19 18:20:45 +01:00
Nico Weber c9276fbfdf Revert "[NFC] Refactor representation of materialized temporaries"
This reverts commit 08ea1ee2db.
It broke ./ClangdTests/FindExplicitReferencesTest.All
on the bots, see comments on https://reviews.llvm.org/D69360
2019-11-17 02:09:25 -05:00
Tyker 08ea1ee2db [NFC] Refactor representation of materialized temporaries
Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360
2019-11-16 17:56:09 +01:00
Reid Kleckner 7177ce978e [SEH] Defer checking filter expression types until instantiaton
While here, wordsmith the error a bit. Now clang says:
  error: filter expression has non-integral type 'Foo'

Fixes PR43779

Reviewers: amccarth

Differential Revision: https://reviews.llvm.org/D69969
2019-11-07 14:52:04 -08:00
Alexey Bataev bef93a98cd [OPENMP50]Treat range-based for as canonical loop.
According to OpenMP 5.0, range-based for is also considered as a
canonical form of loops.

llvm-svn: 373939
2019-10-07 18:54:57 +00:00
Simon Pilgrim 0e82722f9a Remove redundant !HasDependentValue check. NFCI.
Fixes cppcheck warning.

llvm-svn: 373825
2019-10-05 13:20:51 +00:00
Simon Pilgrim 20692a0d3d SemaStmt - silence static analyzer getAs<> null dereference warnings. NFCI.
The static analyzer is warning about potential null dereferences, but we should be able to use castAs<> directly and if not assert will fire for us.

llvm-svn: 373824
2019-10-05 13:20:42 +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
Richard Smith 40c3d6e335 Model converted constant expressions as full-expressions.
This is groundwork for C++20's P0784R7, where non-trivial destructors
can be constexpr, so we need ExprWithCleanups markers in constant
expressions.

No functionality change intended.

llvm-svn: 372359
2019-09-19 22:00:16 +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
Erich Keane 46441fdb3c Implement P1771
As passed in the Cologne meeting and treated by Core as a DR,
[[nodiscard]] was applied to constructors so that they can be diagnosed
in cases where the user forgets a variable name for a type.

The intent is to enable the library to start using this on the
constructors of scope_guard/lock_guard.

Differential Revision: https://reviews.llvm.org/D64914

llvm-svn: 367027
2019-07-25 15:10:56 +00:00
Aaron Ballman 3bef014e7d Implement P1301R4, which allows specifying an optional message on the [[nodiscard]] attribute.
This also bumps the attribute feature test value and introduces the notion of a C++2a extension warning.

llvm-svn: 366626
2019-07-20 07:56:34 +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
Fangrui Song 7264a474b7 Change std::{lower,upper}_bound to llvm::{lower,upper}_bound or llvm::partition_point. NFC
llvm-svn: 365006
2019-07-03 08:13:17 +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
Richard Smith e518235aca Factor out commonality between variable capture initialization and
'this' capture initialization.

llvm-svn: 362317
2019-06-02 04:00:43 +00:00
Richard Smith b5a45bb77e Defer building 'this' captures until we have left the capturing region
and returned to the context in which 'this' should be captured.

This means we now always mark 'this' referenced from the context in
which it's actually referenced, rather than potentially from some
context nested within that.

llvm-svn: 362182
2019-05-31 01:17:04 +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 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
Sam McCall 835d67f6c7 [Sema] Correct typos in return statements so the return types of 'auto' functions are always deduced.
Summary:
e.g.
  auto foo() {
    return no_such_thing; // Return value is a TypoExpr
  }
  using T = decltype(foo()); // Uh-oh, undeduced auto.

Reviewers: rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61649

llvm-svn: 360224
2019-05-08 05:49:42 +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
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
David Blaikie 5e32805050 SemaOverload: Complete candidates before emitting the error, to ensure diagnostics emitted (or suppressed) during completion don't interfere with the overload notes
Because diagnostics and their notes are not connected at the API level,
if the error message for an overload is emitted, then the overload
candidates are completed - if a diagnostic is emitted during that work,
the notes related to overload candidates would be attached to the latter
diagnostic, not the original error. Sort of worse, if the latter
diagnostic was disabled, the notes are disabled.

Reviewers: rsmith

Differential Revision: https://reviews.llvm.org/D61357

llvm-svn: 359854
2019-05-03 00:44:50 +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
David Blaikie a558ee8105 Do not warn on switches over enums that do not use [[maybe_unused]] enumerators
PR36231, [dcl.attr.unused]p3

Reviewers: aaron.ballman

Differential Revision: https://reviews.llvm.org/D61444

llvm-svn: 359800
2019-05-02 16:30:49 +00:00
Fangrui Song 899d13926d Use llvm::stable_sort
llvm-svn: 359098
2019-04-24 14:43:05 +00:00
Alexey Bataev 3167b3035e [CUDA]Delayed diagnostics for the asm instructions.
Adapted targetDiag for the CUDA and used for the delayed diagnostics in
asm constructs. Works for both host and device compilation sides.

Differential Revision: https://reviews.llvm.org/D58463

llvm-svn: 354671
2019-02-22 14:42:48 +00:00
Alexey Bataev 12a21e4b69 Revert "[CUDA]Delayed diagnostics for the asm instructions."
This reverts commit r354593 to fix the problem with the crash on
windows.

llvm-svn: 354596
2019-02-21 16:40:21 +00:00
Alexey Bataev 16d3e1a4d2 [CUDA]Delayed diagnostics for the asm instructions.
Summary:
Adapted targetDiag for the CUDA and used for the delayed diagnostics in
asm constructs. Works for both host and device compilation sides.

Reviewers: tra, jlebar

Subscribers: jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58463

llvm-svn: 354593
2019-02-21 15:51:30 +00:00
Alexey Bataev 7feae05858 [OPENMP] Use targetDiag for diagnostics of unsupported exceptions, NFC.
llvm-svn: 354509
2019-02-20 19:37:17 +00:00
Richard Smith a6e8d5e554 PR40642: Fix determination of whether the final statement of a statement
expression is a discarded-value expression.

Summary:
We used to get this wrong in three ways:

1) During parsing, an expression-statement followed by the }) ending a
   statement expression was always treated as producing the value of the
   statement expression. That's wrong for ({ if (1) expr; })
2) During template instantiation, various kinds of statement (most
   statements not appearing directly in a compound-statement) were not
   treated as discarded-value expressions, resulting in missing volatile
   loads (etc).
3) In all contexts, an expression-statement with attributes was not
   treated as producing the value of the statement expression, eg
   ({ [[attr]] expr; }).

Also fix incorrect enforcement of OpenMP rule that directives can "only
be placed in the program at a position where ignoring or deleting the
directive would result in a program with correct syntax". In particular,
a label (be it goto, case, or default) should not affect whether
directives are permitted.

Reviewers: aaron.ballman, rjmccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D57984

llvm-svn: 354090
2019-02-15 00:27:53 +00:00
Alexey Bataev c416e64731 [OPENMP]Delay emission of the error messages for the exceptions.
Fixed diagnostic emission for the exceptions support in case of the
compilation of OpenMP code for the devices. From now on, it uses delayed
diagnostics mechanism, previously used for CUDA only. It allow to
diagnose not allowed used of exceptions only in functions that are going
to be codegen'ed.

llvm-svn: 353542
2019-02-08 18:02:25 +00:00
Alexey Bataev 346fb4bbcd Revert "[OPENMP]Initial support for the delayed diagnostics."
This reverts commit r353540. Erroneously committed, need to fix the
message and description.

llvm-svn: 353541
2019-02-08 17:42:00 +00:00
Alexey Bataev 5e62adad0d [OPENMP]Initial support for the delayed diagnostics.
It is important to delay the emission of the diagnostic messages for the
functions unless it is proved that the function is going to be used on
the device side. It is required to support compilation with some of the
target-specific system headers.

llvm-svn: 353540
2019-02-08 17:38:09 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Aaron Ballman fb6deeb984 Refactor the way we handle diagnosing unused expression results.
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
2019-01-04 16:58:14 +00:00
Aaron Ballman d23e9bc5af Diagnose an unused result from a call through a function pointer whose return type is marked [[nodiscard]].
When a function returns a type and that type was declared [[nodiscard]], we diagnose any unused results from that call as though the function were marked nodiscard. The same behavior should apply to calls through a function pointer.

This addresses PR31526.

llvm-svn: 350317
2019-01-03 14:24:31 +00:00
Aaron Ballman d914174d9b Switch from static_cast<> to cast<>, update identifier for coding conventions; NFC.
llvm-svn: 349955
2018-12-21 21:11:36 +00:00
Fangrui Song 407659ab0a Revert "Revert r347417 "Re-Reinstate 347294 with a fix for the failures.""
It seems the two failing tests can be simply fixed after r348037

Fix 3 cases in Analysis/builtin-functions.cpp
Delete the bad CodeGen/builtin-constant-p.c for now

llvm-svn: 348053
2018-11-30 23:41:18 +00:00
Fangrui Song f5d3335d75 Revert r347417 "Re-Reinstate 347294 with a fix for the failures."
Kept the "indirect_builtin_constant_p" test case in test/SemaCXX/constant-expression-cxx1y.cpp
while we are investigating why the following snippet fails:

  extern char extern_var;
  struct { int a; } a = {__builtin_constant_p(extern_var)};

llvm-svn: 348039
2018-11-30 21:26:09 +00:00
Hans Wennborg 48ee4ad325 Re-commit r347417 "Re-Reinstate 347294 with a fix for the failures."
This was reverted in r347656 due to me thinking it caused a miscompile of
Chromium. Turns out it was the Chromium code that was broken.

llvm-svn: 347756
2018-11-28 14:04:12 +00:00
Hans Wennborg 8c79706e89 Revert r347417 "Re-Reinstate 347294 with a fix for the failures."
This caused a miscompile in Chrome (see crbug.com/908372) that's
illustrated by this small reduction:

  static bool f(int *a, int *b) {
    return !__builtin_constant_p(b - a) || (!(b - a));
  }

  int arr[] = {1,2,3};

  bool g() {
    return f(arr, arr + 3);
  }

  $ clang -O2 -S -emit-llvm a.cc -o -

g() should return true, but after r347417 it became false for some reason.

This also reverts the follow-up commits.

r347417:
> Re-Reinstate 347294 with a fix for the failures.
>
> Don't try to emit a scalar expression for a non-scalar argument to
> __builtin_constant_p().
>
> Third time's a charm!

r347446:
> The result of is.constant() is unsigned.

r347480:
> A __builtin_constant_p() returns 0 with a function type.

r347512:
> isEvaluatable() implies a constant context.
>
> Assume that we're in a constant context if we're asking if the expression can
> be compiled into a constant initializer. This fixes the issue where a
> __builtin_constant_p() in a compound literal was diagnosed as not being
> constant, even though it's always possible to convert the builtin into a
> constant.

r347531:
> A "constexpr" is evaluated in a constant context. Make sure this is reflected
> if a __builtin_constant_p() is a part of a constexpr.

llvm-svn: 347656
2018-11-27 14:01:40 +00:00
Bill Wendling 6ff1751f7d Re-Reinstate 347294 with a fix for the failures.
Don't try to emit a scalar expression for a non-scalar argument to
__builtin_constant_p().

Third time's a charm!

llvm-svn: 347417
2018-11-21 20:44:18 +00:00
Nico Weber 9f0246d473 Revert r347364 again, the fix was incomplete.
llvm-svn: 347389
2018-11-21 12:47:43 +00:00
Bill Wendling 91549ed15f Reinstate 347294 with a fix for the failures.
EvaluateAsInt() is sometimes called in a constant context. When that's the
case, we need to specify it as so.

llvm-svn: 347364
2018-11-20 23:24:16 +00:00
Bill Wendling 7c44da279e Create ConstantExpr class
A ConstantExpr class represents a full expression that's in a context where a
constant expression is required. This class reflects the path the evaluator
took to reach the expression rather than the syntactic context in which the
expression occurs.

In the future, the class will be expanded to cache the result of the evaluated
expression so that it's not needlessly re-evaluated

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D53475

llvm-svn: 345692
2018-10-31 03:48:47 +00:00
Bruno Ricci 023b1d19f3 [AST] Only store data for the NRVO candidate in ReturnStmt if needed
Only store the NRVO candidate if needed in ReturnStmt.
A good chuck of all of the ReturnStmt have no NRVO candidate
(more than half when parsing all of Boost). For all of them
this saves one pointer. This has no impact on children().

Differential Revision: https://reviews.llvm.org/D53716

Reviewed By: rsmith

llvm-svn: 345605
2018-10-30 14:40:49 +00:00
Bruno Ricci bacf751add [AST] Only store the needed data in WhileStmt
Don't store the data for the condition variable if not needed.
This cuts the size of WhileStmt by up to a pointer.
The order of the children is kept the same.

Differential Revision: https://reviews.llvm.org/D53715

Reviewed By: rjmccall

llvm-svn: 345597
2018-10-30 13:42:41 +00:00
Bruno Ricci e2806f857b [AST] Only store the needed data in SwitchStmt
Don't store the data for the init statement and condition variable
if not needed. This cuts the size of SwitchStmt by up to 2 pointers.
The order of the children is intentionally kept the same.

Also use the newly available space in the bit-fields of Stmt
to store the bit representing whether all enums have been covered
instead of using a PointerIntPair.

Differential Revision: https://reviews.llvm.org/D53714

Reviewed By: rjmccall

llvm-svn: 345510
2018-10-29 16:12:37 +00:00
Bruno Ricci 5b30571753 [AST] Don't store data for GNU range case statement if not needed
Don't store the data for case statements of the form LHS ... RHS if not
needed. This cuts the size of CaseStmt by 1 pointer + 1 SourceLocation in
the common case.

Also use the newly available space in the bit-fields of Stmt to store the
keyword location of SwitchCase and move the small accessor
SwitchCase::getSubStmt to the header.

Differential Revision: https://reviews.llvm.org/D53609

Reviewed By: rjmccall

llvm-svn: 345472
2018-10-28 12:30:53 +00:00
Bruno Ricci b1cc94b2e5 [AST] Only store the needed data in IfStmt
Only store the needed data in IfStmt. This cuts the size of IfStmt
by up to 3 pointers + 1 SourceLocation. The order of the children
is intentionally kept the same even though it would be more
convenient to put the optional trailing objects last. Additionally
use the newly available space in the bit-fields of Stmt to store
the location of the "if".

The result of this is that for the common case of an
if statement of the form:

if (some_cond)
  some_statement

the size of IfStmt is brought down to 8 bytes + 2 pointers,
instead of 8 bytes + 5 pointers + 2 SourceLocation.

Differential Revision: https://reviews.llvm.org/D53607

Reviewed By: rjmccall

llvm-svn: 345464
2018-10-27 21:12:20 +00:00
Richard Trieu f371380fc9 [Sema] Fix -Wcomma for C89
There is a small difference in the scope flags for C89 versus the other C/C++
dialects.  This change ensures that the -Wcomma warning won't be duplicated or
issued in the wrong location.  Also, the test case is refactored into C and C++
parts, with the C++ parts guarded by a #ifdef to allow the test to run in both
modes.

https://bugs.llvm.org/show_bug.cgi?id=32370

llvm-svn: 345228
2018-10-25 01:08:00 +00:00
Richard Trieu 6b13e89ab8 Make -Wfor-loop-analysis work with C++17
For now, disable the "variable in loop condition not modified" warning to not
be emitted when there is a structured binding variable in the loop condition.

https://bugs.llvm.org/show_bug.cgi?id=39285

llvm-svn: 344828
2018-10-20 02:15:58 +00:00
Richard Smith 8baa50013c [cxx2a] P0614R1: Support init-statements in range-based for loops.
We don't yet support this for the case where a range-based for loop is
implicitly rewritten to an ObjC for..in statement.

llvm-svn: 343350
2018-09-28 18:44:09 +00:00
Richard Smith 236ffdeeb2 P0962R1: only use the member form of 'begin' and 'end' in a range-based
for loop if both members exist.

This resolves a DR whereby an errant 'begin' or 'end' member in a base
class could result in a derived class not being usable as a range with
non-member 'begin' and 'end'.

llvm-svn: 342925
2018-09-24 23:17:44 +00:00
Erik Pilkington 3e4e3b17c1 [Sema] Don't warn about omitting unavailable enum constants in a switch
rdar://42717026

Differential revision: https://reviews.llvm.org/D51649

llvm-svn: 341490
2018-09-05 19:13:27 +00:00
Stephen Kelly 1c301dcbc4 Port getLocEnd -> getEndLoc
Reviewers: teemperor!

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D50351

llvm-svn: 339386
2018-08-09 21:09:38 +00:00
Stephen Kelly f2ceec4811 Port getLocStart -> getBeginLoc
Reviewers: teemperor!

Subscribers: jholewinski, whisperity, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D50350

llvm-svn: 339385
2018-08-09 21:08:08 +00:00
Stephen Kelly a6e4358f07 Port getStartLoc -> getBeginLoc
Reviewers: teemperor!

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D50349

llvm-svn: 339384
2018-08-09 21:05:56 +00:00
Fangrui Song 6907ce2f8f Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338291
2018-07-30 19:24:48 +00:00
Richard Smith ef6c43dc0c Refactor checking of switch conditions and case values.
Check each case value in turn while parsing it, performing the
conversion to the switch type within the context of the expression
itself. This will become necessary in order to properly handle cleanups
for temporaries created as part of the case label (in an upcoming
patch). For now it's just good hygiene.

This necessitates moving the checking for the switch condition itself to
earlier, so that the destination type is available when checking the
case labels.

As a nice side-effect, we get slightly improved diagnostic quality and
error recovery by separating the case expression checking from the case
statement checking and from tracking whether there are discarded case
labels.

llvm-svn: 338056
2018-07-26 18:41:30 +00:00
Erich Keane c480f30580 AttributeList de-listifying:
Basically, "AttributeList" loses all list-like mechanisms, ParsedAttributes is
switched to use a TinyPtrVector (and a ParsedAttributesView is created to
have a non-allocating attributes list). DeclaratorChunk gets the later kind,
Declarator/DeclSpec keep ParsedAttributes.

Iterators are added to the ParsedAttribute types so that for-loops work.

llvm-svn: 336945
2018-07-12 21:09:05 +00:00
Taiju Tsuiki 3be68e162f Revert r335019 "Update NRVO logic to support early return (Attempt 2)"
llvm-svn: 335022
2018-06-19 05:35:30 +00:00
Taiju Tsuiki b000a8860e Update NRVO logic to support early return (Attempt 2)
Summary:
This is the second attempt of r333500 (Update NRVO logic to support early return).
The previous one was reverted for a miscompilation for an incorrect NRVO set up on templates such as:
```
struct Foo {};

template <typename T>
T bar() {
  T t;
  if (false)
    return T();
  return t;
}
```

Where, `t` is marked as non-NRVO variable before its instantiation. However, while its instantiation, it's left an NRVO candidate, turned into an NRVO variable later.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D47586

llvm-svn: 335019
2018-06-19 04:39:07 +00:00
Sam McCall 5429bd751c Revert "Update NRVO logic to support early return"
This reverts commit r333500, which causes stage2 compiler crashes.

llvm-svn: 333547
2018-05-30 14:14:58 +00:00
Taiju Tsuiki 44f9c585b9 Update NRVO logic to support early return
Summary:
The previous implementation misses an opportunity to apply NRVO (Named Return Value
Optimization) below. That discourages user to write early return code.

```
struct Foo {};

Foo f(bool b) {
  if (b)
    return Foo();
  Foo oo;
  return oo;
}
```
That is, we can/should apply RVO for a local variable if:
 * It's directly returned by at least one return statement.
 * And, all reachable return statements in its scope returns the variable directly.
While, the previous implementation disables the RVO in a scope if there are multiple return
statements that refers different variables.

On the new algorithm, local variables are in NRVO_Candidate state at first, and a return
statement changes it to NRVO_Disabled for all visible variables but the return statement refers.
Then, at the end of the function AST traversal, NRVO is enabled for variables in NRVO_Candidate
state and refers from at least one return statement.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: xbolva00, Quuxplusone, arthur.j.odwyer, cfe-commits

Differential Revision: https://reviews.llvm.org/D47067

llvm-svn: 333500
2018-05-30 03:53:16 +00:00
Adrian Prantl 9fc8faf9e6 Remove \brief commands from doxygen comments.
This is similar to the LLVM change https://reviews.llvm.org/D46290.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46320

llvm-svn: 331834
2018-05-09 01:00:01 +00:00
Alexey Bataev 1ab3457319 [OPENMP] Enable c++ exceptions outside of the target constructs iff they are
enabled for the host.

If the compilation for the host enables C++ exceptions, but they are not
supported by the device, we still need to allow the code with the
exception handling constructs outside of the target regions.

llvm-svn: 331372
2018-05-02 16:52:07 +00:00
Malcolm Parsons 321f24ec42 Diagnose cases of "return x" that should be "return std::move(x)" for efficiency
Summary:
This patch adds two new diagnostics, which are off by default:

**-Wreturn-std-move**

This diagnostic is enabled by `-Wreturn-std-move`, `-Wmove`, or `-Wall`.
Diagnose cases of `return x` or `throw x`, where `x` is the name of a local variable or parameter, in which a copy operation is performed when a move operation would have been available. The user probably expected a move, but they're not getting a move, perhaps because the type of "x" is different from the return type of the function.
A place where this comes up in the wild is `stdext::inplace_function<Sig, N>` which implements conversion via a conversion operator rather than a converting constructor; see https://github.com/WG21-SG14/SG14/issues/125#issue-297201412
Another place where this has come up in the wild, but where the fix ended up being different, was

    try { ... } catch (ExceptionType ex) {
        throw ex;
    }

where the appropriate fix in that case was to replace `throw ex;` with `throw;`, and incidentally to catch by reference instead of by value. (But one could contrive a scenario where the slicing was intentional, in which case throw-by-move would have been the appropriate fix after all.)
Another example (intentional slicing to a base class) is dissected in https://github.com/accuBayArea/Slides/blob/master/slides/2018-03-07.pdf

**-Wreturn-std-move-in-c++11**

This diagnostic is enabled only by the exact spelling `-Wreturn-std-move-in-c++11`.
Diagnose cases of "return x;" or "throw x;" which in this version of Clang *do* produce moves, but which prior to Clang 3.9 / GCC 5.1 produced copies instead. This is useful in codebases which care about portability to those older compilers.
The name "-in-c++11" is not technically correct; what caused the version-to-version change in behavior here was actually CWG 1579, not C++14. I think it's likely that codebases that need portability to GCC 4.9-and-earlier may understand "C++11" as a colloquialism for "older compilers." The wording of this diagnostic is based on feedback from @rsmith.

**Discussion**

Notice that this patch is kind of a negative-space version of Richard Trieu's `-Wpessimizing-move`. That diagnostic warns about cases of `return std::move(x)` that should be `return x` for speed. These diagnostics warn about cases of `return x` that should be `return std::move(x)` for speed. (The two diagnostics' bailiwicks do not overlap: we don't have to worry about a `return` statement flipping between the two states indefinitely.)

I propose to write a paper for San Diego that would relax the implicit-move rules so that in C++2a the user //would// see the moves they expect, and the diagnostic could be re-worded in a later version of Clang to suggest explicit `std::move` only "in C++17 and earlier." But in the meantime (and/or forever if that proposal is not well received), this diagnostic will be useful to detect accidental copy operations.

Reviewers: rtrieu, rsmith

Reviewed By: rsmith

Subscribers: lebedev.ri, Rakete1111, rsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D43322

Patch by Arthur O'Dwyer.

llvm-svn: 329914
2018-04-12 14:48:48 +00:00
Alexey Bataev c0f879bcec [OPENMP] Additional attributes for the pointer parameters.
Added attributes for better optimization of the OpenMP code.

llvm-svn: 329751
2018-04-10 20:10:53 +00:00
Alexander Kornienko 2a8c18d991 Fix typos in clang
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:

  archtype
  cas
  classs
  checkk
  compres
  definit
  frome
  iff
  inteval
  ith
  lod
  methode
  nd
  optin
  ot
  pres
  statics
  te
  thru

Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)

Differential revision: https://reviews.llvm.org/D44188

llvm-svn: 329399
2018-04-06 15:14:32 +00:00
Akira Hatanaka 673af7a688 Generalize NRVO to cover C structs.
This commit generalizes NRVO to cover C structs (both trivial and
non-trivial structs).

rdar://problem/33599681

Differential Revision: https://reviews.llvm.org/D44968

llvm-svn: 328809
2018-03-29 17:56:24 +00:00
Richard Trieu 09c163bb6b Refactoring code around move/copy initialization. NFC.
Use an enum parameter instead of a bool for more control on how the copy elision
functions work.  Extract the move initialization code from the move or copy
initialization block.

Patch by: Arthur O'Dwyer

Differential Revision: https://reviews.llvm.org/D43898

llvm-svn: 327598
2018-03-15 03:00:55 +00:00
Reid Kleckner 87a3180343 Re-land "[Sema] Make getCurFunction() return null outside function parsing"
This relands r326965.

There was a null dereference in typo correction that was triggered in
Sema/diagnose_if.c. We are not always in a function scope when doing
typo correction. The fix is to add a null check.

LLVM's optimizer made it hard to find this bug. I wrote it up in a
not-very-well-editted blog post here:
http://qinsb.blogspot.com/2018/03/ub-will-delete-your-null-checks.html

llvm-svn: 327334
2018-03-12 21:43:02 +00:00
Reid Kleckner 8d485b845b Revert "[Sema] Make getCurFunction() return null outside function parsing"
This reverts r326965. It seems to have caused repeating test failures in
clang/test/Sema/diagnose_if.c on some buildbots.

I cannot reproduce the problem, and it's not immediately obvious what
the problem is, so let's revert to green.

llvm-svn: 326974
2018-03-08 01:12:22 +00:00
Reid Kleckner c2fd352963 [Sema] Make getCurFunction() return null outside function parsing
Summary:
Before this patch, Sema pre-allocated a FunctionScopeInfo and kept it in
the first, always present element of the FunctionScopes stack. This
meant that Sema::getCurFunction would return a pointer to this
pre-allocated object when parsing code outside a function body. This is
pretty much always a bug, so this patch moves the pre-allocated object
into a separate unique_ptr. This should make bugs like PR36536 a lot
more obvious.

As you can see from this patch, there were a number of places that
unconditionally assumed they were always called inside a function.
However, there are also many places that null checked the result of
getCurFunction(), so I think this is a reasonable direction.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D44039

llvm-svn: 326965
2018-03-08 00:14:34 +00:00
Reid Kleckner 04f9bcaa6d Avoid including ScopeInfo.h from Sema.h
Summary:
This provides no measurable build speedup, but it reinstates an
optimization from r112038 that was lost in r179618.  It requires moving
CapturedScopeInfo::Capture out to clang::sema, which might be too
general since we have plenty of other Capture records in BlockDecl and
other AST nodes.

Reviewers: rjmccall

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D44221

llvm-svn: 326957
2018-03-07 22:48:35 +00:00
Matt Davis b8402ef658 [Debug] Annotate compiler generated range-for loop variables.
Summary:
This change aims to simplify debugging by annotating the range-for loop artificial variables (range, begin, end) with the scope depth. 


Reviewers: rsmith, dblaikie

Reviewed By: dblaikie

Subscribers: dblaikie, cfe-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D42813

llvm-svn: 325175
2018-02-14 21:22:11 +00:00
Richard Smith 6eb9b9e593 Fix crash when trying to pack-expand a GNU statement expression.
We could in principle support such pack expansion, using techniques similar to
what we do for pack expansion of lambdas, but it's not clear it's worthwhile.
For now at least, cleanly reject these cases rather than crashing.

llvm-svn: 324160
2018-02-03 00:44:57 +00:00
Richard Smith 50e291eaf2 Fix and simplify handling of return type for (generic) lambda conversion function to function pointer.
Previously, we would:
 * compute the type of the conversion function and static invoker as a
   side-effect of template argument deduction for a conversion
 * re-compute the type as part of deduced return type deduction when building
   the conversion function itself

Neither of these turns out to be quite correct. There are other ways to reach a
declaration of the conversion function than in a conversion (such as an
explicit call or friend declaration), and performing auto deduction causes the
function type to be rebuilt in the context of the lambda closure type (which is
different from the context in which it originally appeared, resulting in
spurious substitution failures for constructs that are valid in one context but
not the other, such as the use of an enclosing class's "this" pointer).

This patch switches us to use a different strategy: as before, we use the
declared type of the operator() to form the type of the conversion function and
invoker, but we now populate that type as part of return type deduction for the
conversion function. And the invoker is now treated as simply being an
implementation detail of building the conversion function, and isn't given
special treatment by template argument deduction for the conversion function
any more.

llvm-svn: 321683
2018-01-02 23:52:42 +00:00
Benjamin Kramer 0742090e3d [AST] Inline CompoundStmt contents into the parent allocation.
Saves a pointer on every CompoundStmt.

llvm-svn: 321429
2017-12-24 16:24:20 +00:00
Richard Smith c70f1d63f8 [c++20] P0515R3: Parsing support and basic AST construction for operator <=>.
Adding the new enumerator forced a bunch more changes into this patch than I
would have liked. The -Wtautological-compare warning was extended to properly
check the new comparison operator, clang-format needed updating because it uses
precedence levels as weights for determining where to break lines (and several
operators increased their precedence levels with this change), thread-safety
analysis needed changes to build its own IL properly for the new operator.

All "real" semantic checking for this operator has been deferred to a future
patch. For now, we use the relational comparison rules and arbitrarily give
the builtin form of the operator a return type of 'void'.

llvm-svn: 320707
2017-12-14 15:16:18 +00:00
Aaron Ballman c351fba69e Now that C++17 is official (https://www.iso.org/standard/68564.html), start changing the C++1z terminology over to C++17. NFC intended, these are all mechanical changes.
llvm-svn: 319688
2017-12-04 20:27:34 +00:00
Hans Wennborg 59ad150939 Revert r318456 "Issue -Wempty-body warnings for else blocks"
This caused warnings also when the if or else comes from macros. There was an
attempt to fix this in r318556, but that introduced new problems and was
reverted. Reverting this too until the whole issue is sorted.

> This looks like it was just an oversight.
>
> Fixes http://llvm.org/pr35319
>
> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@318456 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-svn: 318667
2017-11-20 17:48:54 +00:00
Hans Wennborg 9541975071 Revert r318556 "Loosen -Wempty-body warning"
It seems this somehow made -Wempty-body fire in some macro cases where
it didn't before, e.g.

  ../../third_party/ffmpeg/libavcodec/bitstream.c(169,5):  error: if statement has empty body [-Werror,-Wempty-body]
      ff_dlog(NULL, "new table index=%d size=%d\n", table_index, table_size);
      ^
  ../../third_party/ffmpeg\libavutil/internal.h(276,80):  note: expanded from macro 'ff_dlog'
  #   define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
                                                                                 ^
  ../../third_party/ffmpeg/libavcodec/bitstream.c(169,5):  note: put the
  semicolon on a separate line to silence this warning

Reverting until this can be figured out.

> Do not show it when `if` or `else` come from macros.
> E.g.,
>
>     #define USED(A) if (A); else
>     #define SOME_IF(A) if (A)
>
>     void test() {
>       // No warnings are shown in those cases now.
>       USED(0);
>       SOME_IF(0);
>     }
>
> Patch by Ilya Biryukov!
>
> Differential Revision: https://reviews.llvm.org/D40185

llvm-svn: 318665
2017-11-20 17:38:16 +00:00
Reid Kleckner c0a81071d3 Loosen -Wempty-body warning
Do not show it when `if` or `else` come from macros.
E.g.,

    #define USED(A) if (A); else
    #define SOME_IF(A) if (A)

    void test() {
      // No warnings are shown in those cases now.
      USED(0);
      SOME_IF(0);
    }

Patch by Ilya Biryukov!

Differential Revision: https://reviews.llvm.org/D40185

llvm-svn: 318556
2017-11-17 21:33:28 +00:00
Reid Kleckner adefb760a8 Issue -Wempty-body warnings for else blocks
This looks like it was just an oversight.

Fixes http://llvm.org/pr35319

llvm-svn: 318456
2017-11-16 21:26:18 +00:00
Richard Trieu 285c93666b Catch more cases with -Wenum-compare
Treat typedef enum as named enums instead of anonymous enums.  Anonymous enums
are ignored by the warning, so previously, typedef enums were ignored as well.

llvm-svn: 312842
2017-09-09 00:25:05 +00:00
Gabor Horvath 0284a20fba [Sema] Assign new flag -Wenum-compare-switch to switch-related parts of -Wenum-compare
Patch by: Reka Nikolett Kovacs

Differential Revision: https://reviews.llvm.org/D36526

llvm-svn: 310521
2017-08-09 20:56:43 +00:00
Gabor Horvath b57e264257 [Sema] -Wenum-compare no longer warn on anonymous enums in switch statements
Patch by: Reka Nikolett Kovacs

llvm-svn: 310468
2017-08-09 12:34:58 +00:00
Gabor Horvath 64c3241154 [Sema] Extend -Wenum-compare to handle mixed enum comparisons in switch statements
Patch by: Reka Nikolett Kovacs

Differential Revision: https://reviews.llvm.org/D36407

llvm-svn: 310449
2017-08-09 08:57:09 +00:00
Eli Friedman e91b2e682c [Sema] Make BreakContinueFinder handle nested loops.
We don't care about break or continue statements that aren't
associated with the current loop, so make sure the visitor
doesn't find them.

Fixes https://bugs.llvm.org/show_bug.cgi?id=32648 .

Differential Revision: https://reviews.llvm.org/D34568

llvm-svn: 307051
2017-07-04 00:52:24 +00:00
Eric Fiselier b936a393ee [coroutines] Fix co_await for range statement
Summary:
Currently we build the co_await expressions on the wrong implicit statements of the implicit ranged for; Specifically we build the co_await expression wrapping the range declaration, but it should wrap the begin expression.

This patch fixes co_await on range for.

Reviewers: rsmith, GorNishanov

Reviewed By: GorNishanov

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D34021

llvm-svn: 305363
2017-06-14 03:24:55 +00:00
Erik Pilkington 21ff345d64 [Sema][C++1z] Ensure binding in dependent range for have non-null type
Fixes PR32172

Differential revision: https://reviews.llvm.org/D34096

llvm-svn: 305195
2017-06-12 16:11:06 +00:00
Alexey Bataev 56223237b0 [DebugInfo] Add kind of ImplicitParamDecl for emission of FlagObjectPointer.
Summary:
If the first parameter of the function is the ImplicitParamDecl, codegen
automatically marks it as an implicit argument with `this` or `self`
pointer. Added internal kind of the ImplicitParamDecl to separate
'this', 'self', 'vtt' and other implicit parameters from other kind of
parameters.

Reviewers: rjmccall, aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D33735

llvm-svn: 305075
2017-06-09 13:40:18 +00:00