866 Commits

Author SHA1 Message Date
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
Lubos Lunak
ab8cde446b make -ftime-trace also print template arguments
Without this, I get e.g. 'PerformPendingInstantiations' -> 'std::fill',
now I get 'std::fill<unsigned long *, int>'.

Differential Revision: https://reviews.llvm.org/D61822

llvm-svn: 360539
2019-05-12 10:39:21 +00:00
Richard Smith
76b9027f35 [c++20] Add support for explicit(bool), as described in P0892R2.
Patch by Tyker!

Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 360311
2019-05-09 03:59:21 +00:00
Hans Wennborg
d2b9fc88c8 Revert r359949 "[clang] adding explicit(bool) from c++2a"
This caused Clang to start erroring on the following:

  struct S {
    template <typename = int> explicit S();
  };

  struct T : S {};

  struct U : T {
    U();
  };
  U::U() {}

  $ clang -c /tmp/x.cc
  /tmp/x.cc:10:4: error: call to implicitly-deleted default constructor of 'T'
  U::U() {}
     ^
  /tmp/x.cc:5:12: note: default constructor of 'T' is implicitly deleted
    because base class 'S' has no default constructor
  struct T : S {};
             ^
  1 error generated.

See discussion on the cfe-commits email thread.

This also reverts the follow-ups r359966 and r359968.

> this patch adds support for the explicit bool specifier.
>
> Changes:
> - The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
> - The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
> - Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
> - Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
> - The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
> - Test for Semantic and Serialization were added.
>
> This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
> Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
>
> Patch by Tyker
>
> Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 360024
2019-05-06 09:51:10 +00:00
Nicolas Lesser
5fe2ddbdf4 [clang] adding explicit(bool) from c++2a
this patch adds support for the explicit bool specifier.

Changes:
- The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
- The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
- Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
- Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
- The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
- Test for Semantic and Serialization were added.

This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.

Patch by Tyker

Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 359949
2019-05-04 00:09:00 +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
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
Anton Afanasyev
d880de2d19 Adds -ftime-trace option to clang that produces Chrome chrome://tracing compatible JSON profiling output dumps.
This change adds hierarchical "time trace" profiling blocks that can be visualized in Chrome, in a "flame chart" style. Each profiling block can have a "detail" string that for example indicates the file being processed, template name being instantiated, function being optimized etc.

This is taken from GitHub PR: https://github.com/aras-p/llvm-project-20170507/pull/2

Patch by Aras Pranckevičius.

Differential Revision: https://reviews.llvm.org/D58675

llvm-svn: 357340
2019-03-30 08:42:48 +00:00
Rafael Auler
9dde31ecc1 Recommit "Support attribute used in member funcs of class templates"
This diff previously exposed a bug in LLVM's IRLinker, breaking
buildbots that tried to self-host LLVM with monolithic LTO.
The bug is now in LLVM by D59552

Original commit message:
As PR17480 describes, clang does not support the used attribute
for member functions of class templates. This means that if the member
function is not used, its definition is never instantiated. This patch
changes clang to emit the definition if it has the used attribute.

Test Plan: Added a testcase

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D56928

llvm-svn: 356598
2019-03-20 19:22:24 +00:00
Richard Trieu
ef1e06df6f Remove an assert in template pack deduction during nested instantiation.
llvm-svn: 356231
2019-03-15 04:26:02 +00:00
Alexey Bataev
9cc10fc926 [OPENMP 5.0]Initial support for 'allocator' clause.
Added parsing/sema analysis/serialization/deserialization for the
'allocator' clause of the 'allocate' directive.

llvm-svn: 355952
2019-03-12 18:52:33 +00:00
Rafael Auler
94b575b23b Revert "Recommit "Support attribute used in member funcs of class templates""
There is nontrivial bug caused in lld that I need to further
investigate. Meanwhile, I'll revert this.

This reverts commit 8297e93480c636dc90fd14653c5a66406193363f.

llvm-svn: 355721
2019-03-08 20:23:57 +00:00
Rafael Auler
2ead8e8993 Recommit "Support attribute used in member funcs of class templates"
The patch originally broke code that was incompatible with GCC, but
we want to follow GCC behavior here according to the discussion in
https://reviews.llvm.org/D58216

Original commit message:
As PR17480 describes, clang does not support the used attribute
for member functions of class templates. This means that if the member
function is not used, its definition is never instantiated. This patch
changes clang to emit the definition if it has the used attribute.

Test Plan: Added a testcase

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D56928

llvm-svn: 355627
2019-03-07 19:14:30 +00:00
Alexey Bataev
25ed0c07c1 [OPENMP 5.0]Add initial support for 'allocate' directive.
Added parsing/sema analysis/serialization/deserialization support for
'allocate' directive.

llvm-svn: 355614
2019-03-07 17:54:44 +00:00
Michael Liao
7557afa000 [AMDGPU] Allow using integral non-type template parameters
Summary:
- Allow using integral non-type template parameters in the following
  attributes

  __attribute__((amdgpu_flat_work_group_size(<min>, <max>)))
  __attribute__((amdgpu_waves_per_eu(<min>[, <max>])))

Reviewers: kzhuravl, yaxunl

Subscribers: jvesely, wdng, nhaehnle, dstuttard, tpr, t-tye, jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58623

llvm-svn: 354909
2019-02-26 18:49:36 +00:00
Michael Kruse
4304e9d143 [OpenMP 5.0] Parsing/sema support for map clause with mapper modifier.
This patch implements the parsing and sema support for OpenMP map
clauses with potential user-defined mapper attached. User defined mapper
is a new feature in OpenMP 5.0. A map clause can have an explicit or
implicit associated mapper, which instructs the compiler to generate
extra data mapping. An example is shown below:

    struct S { int len; int *d; };
    #pragma omp declare mapper(id: struct S s) map(s, s.d[0:s.len])
    struct S ss;
    #pragma omp target map(mapper(id) tofrom: ss) // use the mapper with name 'id' to map ss

Contributed-by: Lingda Li <lildmh@gmail.com>

Differential Revision: https://reviews.llvm.org/D58074

llvm-svn: 354347
2019-02-19 16:38:20 +00:00
Michael Kruse
251e1488e1 [OpenMP 5.0] Parsing/sema support for "omp declare mapper" directive.
This patch implements parsing and sema for "omp declare mapper"
directive. User defined mapper, i.e., declare mapper directive, is a new
feature in OpenMP 5.0. It is introduced to extend existing map clauses
for the purpose of simplifying the copy of complex data structures
between host and device (i.e., deep copy). An example is shown below:

    struct S {  int len;  int *d; };
    #pragma omp declare mapper(struct S s) map(s, s.d[0:s.len]) // Memory region that d points to is also mapped using this mapper.

Contributed-by: Lingda Li <lildmh@gmail.com>

Differential Revision: https://reviews.llvm.org/D56326

llvm-svn: 352906
2019-02-01 20:25:04 +00:00
Rafael Auler
ea94c308ac Revert "Support attribute used in member funcs of class templates"
This reverts commit 352740: broke swift build

llvm-svn: 352748
2019-01-31 13:31:33 +00:00
Rafael Auler
4b70204588 Support attribute used in member funcs of class templates
Summary:
As PR17480 describes, clang does not support the used attribute
for member functions of class templates. This means that if the member
function is not used, its definition is never instantiated. This patch
changes clang to emit the definition if it has the used attribute.

Test Plan: Added a testcase

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D56928

llvm-svn: 352740
2019-01-31 09:38:31 +00:00
Anastasia Stulova
c61eaa5920 Rename getTypeQualifiers to getMethodQualifiers.
Use more descriptive name for the method qualifiers getter.

Differential Revision: https://reviews.llvm.org/D56792

llvm-svn: 352349
2019-01-28 11:37:49 +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
Richard Smith
64095fc07c Remember to instantiate explicit template argument lists in a friend
function declaration.

We'd previously often just drop these on the floor, and friend
redeclaration matching would usually (but not always) figure out the
right redeclaration anyway.

Also, don't try to match a dependent friend function template
specialization to a template until instantiation, and don't forget to
reject qualified friend declarations in dependent contexts that don't
name an already-declared entity.

llvm-svn: 350915
2019-01-11 01:59:33 +00:00
Mikael Nilsson
9d2872db74 [OpenCL] Add generic AS to 'this' pointer
Address spaces are cast into generic before invoking the constructor.

Added support for a trailing Qualifiers object in FunctionProtoType.

Note: This recommits the previously reverted patch, 
      but now it is commited together with a fix for lldb.

Differential Revision: https://reviews.llvm.org/D54862

llvm-svn: 349019
2018-12-13 10:15:27 +00:00
Mikael Nilsson
90646732bf Revert "[OpenCL] Add generic AS to 'this' pointer"
Reverting because the patch broke lldb.

llvm-svn: 348931
2018-12-12 15:06:16 +00:00
Mikael Nilsson
78de84719b [OpenCL] Add generic AS to 'this' pointer
Address spaces are cast into generic before invoking the constructor.

Added support for a trailing Qualifiers object in FunctionProtoType.

Differential Revision: https://reviews.llvm.org/D54862

llvm-svn: 348927
2018-12-12 14:11:59 +00:00
Serge Pavlov
acfcd78aec Diagnose friend function template redefinitions.
Friend function template defined in a class template becomes available if
the enclosing class template is instantiated. Until the function template
is used, it does not have a body, but still is considered a definition for
the purpose of redeclaration checks.

This change modifies redefinition check so that it can find the friend
function template definitions in instantiated classes.

Differential Revision: http://reviews.llvm.org/D21508

llvm-svn: 348473
2018-12-06 09:35:04 +00:00
Richard Smith
6e67142142 Fix crash if an in-class explicit function specialization has explicit
template arguments referring to template paramaeters.

llvm-svn: 348313
2018-12-04 22:26:32 +00:00
George Karpenkov
1657f36c7f [attributes] Add a family of OS_CONSUMED, OS_RETURNS and OS_RETURNS_RETAINED attributes
The addition adds three attributes for communicating ownership,
analogous to existing NS_ and CF_ attributes.
The attributes are meant to be used for communicating ownership of all
objects in XNU (Darwin kernel) and all of the kernel modules.
The ownership model there is very similar, but still different from the
Foundation model, so we think that introducing a new family of
attributes is appropriate.

The addition required a sizeable refactoring of the existing code for
CF_ and NS_ ownership attributes, due to tight coupling and the fact
that differentiating between the types was previously done using a
boolean.

Differential Revision: https://reviews.llvm.org/D54912

llvm-svn: 347947
2018-11-30 02:18:37 +00:00
Hans Wennborg
262baa4753 Follow-up to r345699: Call CheckStaticLocalForDllExport later for templates
Calling it too early might cause dllimport to get inherited onto the
VarDecl before the initializer got attached. See the test case for an
example where this broke things.

llvm-svn: 345709
2018-10-31 10:34:46 +00:00
Hans Wennborg
59f18f1b72 [clang-cl] Inherit dllexport to static locals also in template instantiations (PR39496)
In the course of D51340, @takuto.ikuta discovered that Clang fails to put
dllexport/import attributes on static locals during template instantiation.

For regular functions, this happens in Sema::FinalizeDeclaration(), however for
template instantiations we need to do something in or around
TemplateDeclInstantiator::VisitVarDecl(). This patch does that, and extracts
the code to a utility function.

Differential Revision: https://reviews.llvm.org/D53870

llvm-svn: 345699
2018-10-31 08:38:48 +00:00
Kelvin Li
1408f91a25 [OPENMP] Add support for OMP5 requires directive + unified_address clause
Add support for OMP5.0 requires directive and unified_address clause.
Patches to follow will include support for additional clauses.

Differential Revision: https://reviews.llvm.org/D52359

llvm-svn: 343063
2018-09-26 04:28:39 +00:00
Louis Dionne
3c011e1e3c [clang] Make sure attributes on member classes are applied properly
Summary:
Attributes on member classes of class templates and member class templates
of class templates are not currently instantiated. This was discovered by
Richard Smith here:

  http://lists.llvm.org/pipermail/cfe-dev/2018-September/059291.html

This commit makes sure that attributes are instantiated properly. This
commit does not fix the broken behavior for member partial and explicit
specializations of class templates.

PR38913

Reviewers: rsmith

Subscribers: dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D51997

llvm-svn: 342238
2018-09-14 14:07:16 +00:00
Alexey Bataev
e6aa4694de [OPENMP] Fix PR38903: Crash on instantiation of the non-dependent
declare reduction.

If the declare reduction construct with the non-dependent type is
defined in the template construct, the compiler might crash on the
template instantition. Reworked the whole instantiation scheme for the
declare reduction constructs to fix this problem correctly.

llvm-svn: 342151
2018-09-13 16:54:05 +00:00
Richard Smith
c457766c6d Consistently create a new declaration when merging a pre-existing but
hidden definition with a would-be-parsed redefinition.

This permits a bunch of cleanups. In particular, we no longer need to
take merged definitions into account when checking declaration
visibility, only when checking definition visibility, which makes
certain visibility checks take linear instead of quadratic time.

We could also now remove the UPD_DECL_EXPORTED update record and track
on each declaration whether it was demoted from a definition (as we
already do for variables), but I'm not doing that in this patch to keep
the changes here simpler.

llvm-svn: 342018
2018-09-12 02:13:47 +00:00
Richard Smith
5159bbad8b PR38627: Fix handling of exception specification adjustment for
destructors.

We previously tried to patch up the exception specification after
completing the class, which went wrong when the exception specification
was needed within the class body (in particular, by a friend
redeclaration of the destructor in a nested class). We now mark the
destructor as having a not-yet-computed exception specification
immediately after creating it.

This requires delaying various checks against the exception
specification (where we'd previously have just got the wrong exception
specification, and now find we have an exception specification that we
can't compute yet) when those checks fire while the class is being
defined.

This also exposed an issue that we were missing a CodeSynthesisContext
for computation of exception specifications (otherwise we'd fail to make
the module containing the definition of the class visible when computing
its members' exception specs). Adding that incidentally also gives us a
diagnostic quality improvement.

This has also exposed an pre-existing problem: making the exception
specification evaluation context a non-SFINAE context (as it should be)
results in a bootstrap failure; PR38850 filed for this.

llvm-svn: 341499
2018-09-05 22:30:37 +00:00
Erich Keane
0fb16483ac Enforce instantiation of template multiversion functions
Multiversioned member functions inside of a template type were 
not properly being emitted.  The solution to this is to simply 
ensure that their bodies are correctly evaluated/assigned during
template instantiation.

llvm-svn: 339597
2018-08-13 18:33:20 +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
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
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
Artem Belevich
e9fa53a09b [CUDA] Check initializers of instantiated template variables.
We were already performing checks on non-template variables,
but the checks on templated ones were missing.

Differential Revision: https://reviews.llvm.org/D45231

llvm-svn: 334143
2018-06-06 22:37:25 +00:00
Richard Smith
2600c63d96 PR34520: after instantiating a non-templated member deduction guide, don't forget to push it into the class scope.
llvm-svn: 333589
2018-05-30 20:24:10 +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
Faisal Vali
a534f07f8c Revert rC330794 and some dependent tiny bug fixes
See Richard's humbling feedback here: 
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226482.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226486.html

Wish I'd had the patience to solicit the feedback prior to committing :)

Sorry for the noise guys.

Thank you Richard for being the steward that clang deserves!

llvm-svn: 330888
2018-04-26 00:42:40 +00:00
Faisal Vali
936de9d666 [c++2a] [concepts] Add rudimentary parsing support for template concept declarations
This patch is a tweak of changyu's patch: https://reviews.llvm.org/D40381. It differs in that the recognition of the 'concept' token is moved into the machinery that recognizes declaration-specifiers - this allows us to leverage the attribute handling machinery more seamlessly.

See the test file to get a sense of the basic parsing that this patch supports. 

There is much more work to be done before concepts are usable...

Thanks Changyu!

llvm-svn: 330794
2018-04-25 02:42:26 +00:00
Artem Belevich
67d22c8a84 Revert "[CUDA] Check initializers of instantiated template variables."
This (temporarily) reverts commit r329127 due to the problems
it exposed in TensorFlow.

llvm-svn: 329229
2018-04-04 20:48:42 +00:00
Artem Belevich
d9189d1e76 [CUDA] Check initializers of instantiated template variables.
We were already performing checks on non-template variables,
but the checks on templated ones were missing.

Differential Revision: https://reviews.llvm.org/D45231

llvm-svn: 329127
2018-04-03 22:41:06 +00:00
George Karpenkov
ec38cf7aed [ast] Do not auto-initialize Objective-C for-loop variables in Objective-C++ in templatized code under ARC
The AST for the fragment

```
@interface I
@end

template <typename>
void decode(I *p) {
  for (I *k in p) {}
}

void decode(I *p) {
  decode<int>(p);
}
```

differs heavily when templatized and non-templatized:

```
|-FunctionTemplateDecl 0x7fbfe0863940 <line:4:1, line:7:1> line:5:6 decode
| |-TemplateTypeParmDecl 0x7fbfe0863690 <line:4:11> col:11 typename depth 0 index 0
| |-FunctionDecl 0x7fbfe08638a0 <line:5:1, line:7:1> line:5:6 decode 'void (I *__strong)'
| | |-ParmVarDecl 0x7fbfe08637a0 <col:13, col:16> col:16 referenced p 'I *__strong'
| | `-CompoundStmt 0x7fbfe0863b88 <col:19, line:7:1>
| |   `-ObjCForCollectionStmt 0x7fbfe0863b50 <line:6:3, col:20>
| |     |-DeclStmt 0x7fbfe0863a50 <col:8, col:13>
| |     | `-VarDecl 0x7fbfe08639f0 <col:8, col:11> col:11 k 'I *const __strong'
| |     |-ImplicitCastExpr 0x7fbfe0863a90 <col:16> 'I *' <LValueToRValue>
| |     | `-DeclRefExpr 0x7fbfe0863a68 <col:16> 'I *__strong' lvalue ParmVar 0x7fbfe08637a0 'p' 'I *__strong'
| |     `-CompoundStmt 0x7fbfe0863b78 <col:19, col:20>
| `-FunctionDecl 0x7fbfe0863f80 <line:5:1, line:7:1> line:5:6 used decode 'void (I *__strong)'
|   |-TemplateArgument type 'int'
|   |-ParmVarDecl 0x7fbfe0863ef8 <col:13, col:16> col:16 used p 'I *__strong'
|   `-CompoundStmt 0x7fbfe0890cf0 <col:19, line:7:1>
|     `-ObjCForCollectionStmt 0x7fbfe0890cc8 <line:6:3, col:20>
|       |-DeclStmt 0x7fbfe0890c70 <col:8, col:13>
|       | `-VarDecl 0x7fbfe0890c00 <col:8, col:11> col:11 k 'I *__strong' callinit
|       |   `-ImplicitValueInitExpr 0x7fbfe0890c60 <<invalid sloc>> 'I *__strong'
|       |-ImplicitCastExpr 0x7fbfe0890cb0 <col:16> 'I *' <LValueToRValue>
|       | `-DeclRefExpr 0x7fbfe0890c88 <col:16> 'I *__strong' lvalue ParmVar 0x7fbfe0863ef8 'p' 'I *__strong'
|       `-CompoundStmt 0x7fbfe0863b78 <col:19, col:20>
```

Note how in the instantiated version ImplicitValueInitExpr unexpectedly appears.

While objects are auto-initialized under ARC, it does not make sense to
have an initializer for a for-loop variable, and it makes even less
sense to have such a different AST for instantiated and non-instantiated
version.

Digging deeper, I have found that there are two separate Sema* files for
dealing with templates and for dealing with non-templatized code.
In a non-templatized version, an initialization was performed only for
variables which are not loop variables for an Objective-C loop and not
variables for a C++ for-in loop:

```
  if (FRI && (Tok.is(tok::colon) || isTokIdentifier_in())) {
    bool IsForRangeLoop = false;
    if (TryConsumeToken(tok::colon, FRI->ColonLoc)) {
      IsForRangeLoop = true;
      if (Tok.is(tok::l_brace))
        FRI->RangeExpr = ParseBraceInitializer();
      else
        FRI->RangeExpr = ParseExpression();
    }

    Decl *ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
    if (IsForRangeLoop)
      Actions.ActOnCXXForRangeDecl(ThisDecl);
    Actions.FinalizeDeclaration(ThisDecl);
    D.complete(ThisDecl);
    return Actions.FinalizeDeclaratorGroup(getCurScope(), DS, ThisDecl);
  }

  SmallVector<Decl *, 8> DeclsInGroup;
  Decl *FirstDecl = ParseDeclarationAfterDeclaratorAndAttributes(
      D, ParsedTemplateInfo(), FRI);
```

However the code in SemaTemplateInstantiateDecl was inconsistent,
guarding only against C++ for-in loops.

rdar://38391075

Differential Revision: https://reviews.llvm.org/D44989

llvm-svn: 328749
2018-03-29 00:56:24 +00:00