Commit Graph

763 Commits

Author SHA1 Message Date
Adrian Prantl 43580a5c5a Allow remapping Clang module skeleton CU references with -fdebug-prefix-map
Differential Revision: https://reviews.llvm.org/D76383
2020-03-20 15:15:56 -07:00
Adrian Prantl 079c6ddaf5 Correctly initialize the DW_AT_comp_dir attribute of Clang module skeleton CUs
Before this patch a Clang module skeleton CU would have a
DW_AT_comp_dir pointing to the directory of the module map file, and
this information was not used by anyone. Even worse, LLDB actually
resolves relative DWO paths by appending it to DW_AT_comp_dir. This
patch sets it to the same directory that is used as the main CU's
compilation directory, which would make the LLDB code work.

Differential Revision: https://reviews.llvm.org/D76377
2020-03-20 14:18:14 -07:00
Roman Lebedev d5edcb9064
[clang] Prune 'IsOMPStructuredBlock' Stmt bit
As discussed in https://reviews.llvm.org/D59214#1916596
and in some other reviews dealing with FPenv,
bits in Stmt are scarce, and i got so burnout with D59214
and https://bugs.llvm.org/show_bug.cgi?id=40563 specifically
that i never actually followed up with the usages for this bit.

So let's unhoard it, at least for now?
2020-03-12 14:48:57 +03:00
Akira Hatanaka 40568fec7e [CodeGen] Emit destructor calls to destruct compound literals
Fix a bug in IRGen where it wasn't destructing compound literals in C
that are ObjC pointer arrays or non-trivial structs. Also diagnose jumps
that enter or exit the lifetime of the compound literals.

rdar://problem/51867864

Differential Revision: https://reviews.llvm.org/D64464
2020-03-10 14:08:28 -07:00
Saar Raz 7fb562c1ab [Concepts] Add constraints checks to isSameEntity
isSameEntity was missing constraints checking, causing constrained overloads
to not travel well accross serialization. (bug #45115)

Add constraints checking to isSameEntity.
2020-03-10 22:05:36 +02:00
Sjoerd Meijer 3d9a0445cc Recommit #2 "[Driver] Default to -fno-common for all targets"
After a first attempt to fix the test-suite failures, my first recommit
caused the same failures again. I had updated CMakeList.txt files of
tests that needed -fcommon, but it turns out that there are also
Makefiles which are used by some bots, so I've updated these Makefiles
now too.

See the original commit message for more details on this change:
0a9fc9233e
2020-03-09 19:57:03 +00:00
Sjoerd Meijer f35d112efd Revert "Recommit "[Driver] Default to -fno-common for all targets""
This reverts commit 2c36c23f34.

Still problems in the test-suite, which I really thought I had fixed...
2020-03-09 10:37:28 +00:00
Sjoerd Meijer 2c36c23f34 Recommit "[Driver] Default to -fno-common for all targets"
This includes fixes for:
- test-suite: some benchmarks need to be compiled with -fcommon, see D75557.
- compiler-rt: one test needed -fcommon, and another a change, see D75520.
2020-03-09 10:07:37 +00:00
Sjoerd Meijer 4e363563fa Revert "[Driver] Default to -fno-common for all targets"
This reverts commit 0a9fc9233e.

Going to look at the asan failures.

I find the failures in the test suite weird, because they look
like compile time test and I don't understand how that can be
failing, but will have a brief look at that too.
2020-03-03 10:00:36 +00:00
Sjoerd Meijer 0a9fc9233e [Driver] Default to -fno-common for all targets
This makes -fno-common the default for all targets because this has performance
and code-size benefits and is more language conforming for C code.
Additionally, GCC10 also defaults to -fno-common and so we get consistent
behaviour with GCC.

With this change, C code that uses tentative definitions as definitions of a
variable in multiple translation units will trigger multiple-definition linker
errors. Generally, this occurs when the use of the extern keyword is neglected
in the declaration of a variable in a header file. In some cases, no specific
translation unit provides a definition of the variable. The previous behavior
can be restored by specifying -fcommon.

As GCC has switched already, we benefit from applications already being ported
and existing documentation how to do this. For example:
- https://gcc.gnu.org/gcc-10/porting_to.html
- https://wiki.gentoo.org/wiki/Gcc_10_porting_notes/fno_common

Differential revision: https://reviews.llvm.org/D75056
2020-03-03 09:15:07 +00:00
Hans Wennborg 7ea9a6e022 Revert "make -fmodules-codegen and -fmodules-debuginfo work also with PCHs"
This caused PR44953. See also the discussion on D74846.

This reverts commit cbc9d22e49.
2020-02-27 14:33:43 +01:00
Fangrui Song dbc96b518b Revert "[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition"
This reverts commit 789a46f2d7.

Accidentally committed.
2020-02-03 10:09:39 -08:00
Fangrui Song 789a46f2d7 [CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition
Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.

Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.

Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert

Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73865
2020-02-03 09:52:48 -08:00
Saar Raz 67c608a969 [Concepts] Deprecate -fconcepts-ts, enable Concepts under -std=c++2a
Now with concepts support merged and mostly complete, we do not need -fconcepts-ts
(which was also misleading as we were not implementing the TS) and can enable
concepts features under C++2a. A warning will be generated if users still attempt
to use -fconcepts-ts.
2020-01-24 00:48:59 +02:00
Saar Raz a0f50d7316 [Concepts] Requires Expressions
Implement support for C++2a requires-expressions.

Re-commit after compilation failure on some platforms due to alignment issues with PointerIntPair.

Differential Revision: https://reviews.llvm.org/D50360
2020-01-19 00:23:26 +02:00
Saar Raz baa84d8cde Revert "[Concepts] Requires Expressions"
This reverts commit 0279318997.

There have been some failing tests on some platforms, reverting while investigating.
2020-01-18 14:58:01 +02:00
Saar Raz 0279318997 [Concepts] Requires Expressions
Implement support for C++2a requires-expressions.

Differential Revision: https://reviews.llvm.org/D50360
2020-01-18 09:15:36 +02:00
Reid Kleckner c42116cc65 Fix up ms-pch-macro.c test to pass on non-Windows 2020-01-14 22:19:30 -08:00
Zachary Henkel 0f9cf42fac Allow /D flags absent during PCH creation under msvc-compat
Summary:
Before this patch adding a new /D flag when compiling a source file that consumed a PCH with clang-cl would issue a diagnostic and then fail.  With the patch, the diagnostic is still issued but the definition is accepted.  This matches the msvc behavior.  The fuzzy-pch-msvc.c is a clone of the existing fuzzy-pch.c tests with some msvc specific rework.

msvc diagnostic:
  warning C4605: '/DBAR=int' specified on current command line, but was not specified when precompiled header was built

Output of the CHECK-BAR test prior to the code change:
  <built-in>(1,9): warning: definition of macro 'BAR' does not match definition in precompiled header [-Wclang-cl-pch]
  #define BAR int
          ^
  D:\repos\llvm\llvm-project\clang\test\PCH\fuzzy-pch-msvc.c(12,1): error: unknown type name 'BAR'
  BAR bar = 17;
  ^
  D:\repos\llvm\llvm-project\clang\test\PCH\fuzzy-pch-msvc.c(23,4): error: BAR was not defined
  #  error BAR was not defined
     ^
  1 warning and 2 errors generated.

Reviewers: rnk, thakis, hans, zturner

Subscribers: mikerice, aganea, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D72405
2020-01-14 17:26:01 -08:00
Luboš Luňák cbc9d22e49 make -fmodules-codegen and -fmodules-debuginfo work also with PCHs
Allow to build PCH's (with -building-pch-with-obj and the extra .o file)
with -fmodules-codegen -fmodules-debuginfo to allow emitting shared code
into the extra .o file, similarly to how it works with modules. A bit of
a misnomer, but the underlying functionality is the same. This saves up
to 20% of build time here.

Differential Revision: https://reviews.llvm.org/D69778
2020-01-15 00:01:08 +01:00
Richard Smith 2519554134 When diagnosing the lack of a viable conversion function, also list
explicit functions that are not candidates.

It's not always obvious that the reason a conversion was not possible is
because the function you wanted to call is 'explicit', so explicitly say
if that's the case.

It would be nice to rank the explicit candidates higher in the
diagnostic if an implicit conversion sequence exists for their
arguments, but unfortunately we can't determine that without potentially
triggering non-immediate-context errors that we're not permitted to
produce.
2020-01-09 15:15:02 -08:00
Richard Smith f495de43bd [c++20] P1959R0: Remove support for std::*_equality. 2019-12-16 17:49:45 -08:00
John McCall 803403afc8 Fix a bug in the property-based serialization of
dependent template names.

Apparently we didn't test this in the test suite because we have
a lot of redundant ways of representing this situation that kick
in in the more common situations.  For example, DependentTST stores
a qualifier + identifier pair rather than a TemplateName.
2019-12-16 16:08:09 -05:00
Richard Smith 848934c67d [c++20] Fix handling of unqualified lookups from a defaulted comparison
function.

We need to perform unqualified lookups from the context of a defaulted
comparison, but not until we implicitly define the function, at which
point we can't do those lookups any more. So perform the lookup from the
end of the class containing the =default declaration and store the
lookup results on the defaulted function until we synthesize the body.
2019-12-09 17:40:36 -08:00
Eric Christopher fd39b1bb20 Revert "Revert "As a follow-up to my initial mail to llvm-dev here's a first pass at the O1 described there.""
This reapplies: 8ff85ed905

Original commit message:

As a follow-up to my initial mail to llvm-dev here's a first pass at the O1 described there.

This change doesn't include any change to move from selection dag to fast isel
and that will come with other numbers that should help inform that decision.
There also haven't been any real debuggability studies with this pipeline yet,
this is just the initial start done so that people could see it and we could start
tweaking after.

Test updates: Outside of the newpm tests most of the updates are coming from either
optimization passes not run anymore (and without a compelling argument at the moment)
that were largely used for canonicalization in clang.

Original post:

http://lists.llvm.org/pipermail/llvm-dev/2019-April/131494.html

Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65410

This reverts commit c9ddb02659.
2019-11-26 20:28:52 -08:00
Muhammad Omair Javaid c9ddb02659 Revert "As a follow-up to my initial mail to llvm-dev here's a first pass at the O1 described there."
This reverts commit 8ff85ed905.

This commit introduced 9 new failures on lldb buildbot host at http://lab.llvm.org:8014/builders/lldb-aarch64-ubuntu

Following tests were failing:
    lldb-api :: functionalities/tail_call_frames/ambiguous_tail_call_seq1/TestAmbiguousTailCallSeq1.py
    lldb-api :: functionalities/tail_call_frames/ambiguous_tail_call_seq2/TestAmbiguousTailCallSeq2.py
    lldb-api :: functionalities/tail_call_frames/disambiguate_call_site/TestDisambiguateCallSite.py
    lldb-api :: functionalities/tail_call_frames/disambiguate_paths_to_common_sink/TestDisambiguatePathsToCommonSink.py
    lldb-api :: functionalities/tail_call_frames/disambiguate_tail_call_seq/TestDisambiguateTailCallSeq.py
    lldb-api :: functionalities/tail_call_frames/inlining_and_tail_calls/TestInliningAndTailCalls.py
    lldb-api :: functionalities/tail_call_frames/sbapi_support/TestTailCallFrameSBAPI.py
    lldb-api :: functionalities/tail_call_frames/thread_step_out_message/TestArtificialFrameStepOutMessage.py
    lldb-api :: functionalities/tail_call_frames/thread_step_out_or_return/TestSteppingOutWithArtificialFrames.py
    lldb-api :: functionalities/tail_call_frames/unambiguous_sequence/TestUnambiguousTailCalls.py

Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65410
2019-11-26 09:32:13 +05:00
Eric Christopher 8ff85ed905 As a follow-up to my initial mail to llvm-dev here's a first pass at the O1 described there.
This change doesn't include any change to move from selection dag to fast isel
and that will come with other numbers that should help inform that decision.
There also haven't been any real debuggability studies with this pipeline yet,
this is just the initial start done so that people could see it and we could start
tweaking after.

Test updates: Outside of the newpm tests most of the updates are coming from either
optimization passes not run anymore (and without a compelling argument at the moment)
that were largely used for canonicalization in clang.

Original post:

http://lists.llvm.org/pipermail/llvm-dev/2019-April/131494.html

Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65410
2019-11-25 17:16:46 -08:00
Dávid Bolvanský 1da13237a4 [Diagnostics] Try to improve warning message for -Wreturn-type
Summary: I agree with https://easyaspi314.github.io/gcc-vs-clang.html?fbclid=IwAR1VA0qxiWVUusOQUv5z7JESS7ZpeJy-UqAI5mnJscofGLqXcqeErIUB2gU, current warning message is not very good. We should try to improve it..

Reviewers: rsmith, aaron.ballman, easyaspi314

Reviewed By: aaron.ballman

Subscribers: arphaman, Quuxplusone, mehdi_amini, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69762
2019-11-09 17:54:58 +01:00
Adrian Prantl 122e7af03d PCH debug info: Avoid appending the source directory to an absolute path
When building a precompiled header in -fmodule-format=obj (i.e.,
`-gmodules) in an absolute path, the locig in
CGDebugInfo::createCompileUnit would unconditionally append the source
directory to the -main-file-name. This patch avoids that behavior for
absolute paths.

rdar://problem/46045865

Differential Revision: https://reviews.llvm.org/D69213

llvm-svn: 375423
2019-10-21 16:44:37 +00:00
Richard Smith 974c8b7e2f [c++20] Add rewriting from comparison operators to <=> / ==.
This adds support for rewriting <, >, <=, and >= to a normal or reversed
call to operator<=>, for rewriting != to a normal or reversed call to
operator==, and for rewriting <=> and == to reversed forms of those same
operators.

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

llvm-svn: 375306
2019-10-19 00:04:43 +00:00
Saar Raz 5d98ba6077 [Concepts] Concept Specialization Expressions
Part of C++20 Concepts implementation effort. Added Concept Specialization Expressions that are created when a concept is refe$

D41217 on Phabricator.

(recommit after fixing failing Parser test on windows)

llvm-svn: 374903
2019-10-15 15:24:26 +00:00
Nico Weber b4638f9ff0 Revert 374882 "[Concepts] Concept Specialization Expressions"
This reverts commit ec87b00382.
The test fails on Windows, see e.g.
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/11533/steps/stage%201%20check/logs/stdio

Also revert follow-up r374893.

llvm-svn: 374899
2019-10-15 14:46:39 +00:00
Bruno Cardoso Lopes 1731fc88d1 Reapply: [Modules][PCH] Hash input files content
Summary:
When files often get touched during builds, the mtime based validation
leads to different problems in implicit modules builds, even when the
content doesn't actually change:

- Modules only: module invalidation due to out of date files. Usually causing rebuild traffic.
- Modules + PCH: build failures because clang cannot rebuild a module if it comes from building a PCH.
- PCH: build failures because clang cannot rebuild a PCH in case one of the input headers has different mtime.

This patch proposes hashing the content of input files (headers and
module maps), which is performed during serialization time. When looking
at input files for validation, clang only computes the hash in case
there's a mtime mismatch.

I've tested a couple of different hash algorithms availble in LLVM in
face of building modules+pch for `#import <Cocoa/Cocoa.h>`:
- `hash_code`: performace diff within the noise, total module cache increased by 0.07%.
- `SHA1`: 5% slowdown. Haven't done real size measurements, but it'd be BLOCK_ID+20 bytes per input file, instead of BLOCK_ID+8 bytes from `hash_code`.
- `MD5`: 3% slowdown. Like above, but BLOCK_ID+16 bytes per input file.

Given the numbers above, the patch uses `hash_code`. The patch also
improves invalidation error msgs to point out which type of problem the
user is facing: "mtime", "size" or "content".

rdar://problem/29320105

Reviewers: dexonsmith, arphaman, rsmith, aprantl

Subscribers: jkorous, cfe-commits, ributzka

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67249

> llvm-svn: 374841

llvm-svn: 374895
2019-10-15 14:23:55 +00:00
Saar Raz ec87b00382 [Concepts] Concept Specialization Expressions
Part of C++20 Concepts implementation effort. Added Concept Specialization Expressions that are created when a concept is referenced with arguments, and tests thereof.

llvm-svn: 374882
2019-10-15 11:48:58 +00:00
Eric Christopher 3be9169caa Temporarily Revert [Modules][PCH] Hash input files content
as it's breaking a few bots.

This reverts r374841 (git commit 2a1386c81d)

llvm-svn: 374842
2019-10-14 23:14:24 +00:00
Bruno Cardoso Lopes 2a1386c81d [Modules][PCH] Hash input files content
Summary:
When files often get touched during builds, the mtime based validation
leads to different problems in implicit modules builds, even when the
content doesn't actually change:

- Modules only: module invalidation due to out of date files. Usually causing rebuild traffic.
- Modules + PCH: build failures because clang cannot rebuild a module if it comes from building a PCH.
- PCH: build failures because clang cannot rebuild a PCH in case one of the input headers has different mtime.

This patch proposes hashing the content of input files (headers and
module maps), which is performed during serialization time. When looking
at input files for validation, clang only computes the hash in case
there's a mtime mismatch.

I've tested a couple of different hash algorithms availble in LLVM in
face of building modules+pch for `#import <Cocoa/Cocoa.h>`:
- `hash_code`: performace diff within the noise, total module cache increased by 0.07%.
- `SHA1`: 5% slowdown. Haven't done real size measurements, but it'd be BLOCK_ID+20 bytes per input file, instead of BLOCK_ID+8 bytes from `hash_code`.
- `MD5`: 3% slowdown. Like above, but BLOCK_ID+16 bytes per input file.

Given the numbers above, the patch uses `hash_code`. The patch also
improves invalidation error msgs to point out which type of problem the
user is facing: "mtime", "size" or "content".

rdar://problem/29320105

Reviewers: dexonsmith, arphaman, rsmith, aprantl

Subscribers: jkorous, cfe-commits, ributzka

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67249

llvm-svn: 374841
2019-10-14 23:02:03 +00:00
Reid Kleckner 38e033bf33 Re-land Remove REQUIRES:shell from tests that pass for me on Windows
This reverts r371497 (git commit 3d7e9ab7b9)

Reorder `not` with `env` in these two tests so they pass:
  Driver/rewrite-map-in-diagnostics.c
  Index/crash-recovery-modules.m.

This will not be necessary after D66531 lands.

llvm-svn: 371552
2019-09-10 20:15:45 +00:00
James Henderson 3d7e9ab7b9 Revert Remove REQUIRES:shell from tests that pass for me on Windows
This reverts r371478 (git commit a9980f60ce)

llvm-svn: 371497
2019-09-10 08:48:33 +00:00
Reid Kleckner a9980f60ce Remove REQUIRES:shell from tests that pass for me on Windows
I see in the history for some of these tests REQUIRES:shell was used as
a way to disable tests on Windows because they are flaky there. I tried
not to re-enable such tests, but it's possible that I missed some and
this will re-enable flaky tests on Windows. If so, we should disable
them with UNSUPPORTED:system-windows and add a comment that they are
flaky there. So far as I can tell, the lit internal shell is capable of
running all of these tests, and we shouldn't use REQUIRES:shell as a
proxy for Windows.

llvm-svn: 371478
2019-09-10 00:50:32 +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
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
Aaron Ballman 774bd6ef1c Diagnose use of _Thread_local as an extension when not in C11 mode.
llvm-svn: 369954
2019-08-26 19:44:07 +00:00
Sam McCall 0c1da4a796 Rename PCH/leakfiles test so it runs on bots.
llvm-svn: 368455
2019-08-09 17:13:56 +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
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
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
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
Richard Smith dcf17ded66 Convert MemberExpr creation and serialization to work the same way as
most / all other Expr subclasses.

This reinstates r362551, reverted in r362597, with a fix to a bug that
caused MemberExprs to sometimes have a null FoundDecl after a round-trip
through an AST file.

llvm-svn: 362756
2019-06-06 23:24:15 +00:00
Jennifer Yu b8fee677bf Re-check in clang support gun asm goto after fixing tests.
llvm-svn: 362410
2019-06-03 15:57:25 +00:00
Erich Keane d0f34fd198 Revert "clang support gnu asm goto."
This reverts commit 954ec09aed.

Reverting due to test failures as requested by Jennifer Yu.

Conflicts:
	clang/test/CodeGen/asm-goto.c

llvm-svn: 362106
2019-05-30 15:38:02 +00:00