Commit Graph

98 Commits

Author SHA1 Message Date
Matheus Izvekov 15f3cd6bfc
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could expose a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-27 11:10:54 +02:00
Jonas Devlieghere 888673b6e3
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit 7c51f02eff because it
stills breaks the LLDB tests. This was  re-landed without addressing the
issue or even agreement on how to address the issue. More details and
discussion in https://reviews.llvm.org/D112374.
2022-07-14 21:17:48 -07:00
Matheus Izvekov 7c51f02eff
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could exposed a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-15 04:16:55 +02:00
Jonas Devlieghere 3968936b92
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit bdc6974f92 because it
breaks all the LLDB tests that import the std module.

  import-std-module/array.TestArrayFromStdModule.py
  import-std-module/deque-basic.TestDequeFromStdModule.py
  import-std-module/deque-dbg-info-content.TestDbgInfoContentDequeFromStdModule.py
  import-std-module/forward_list.TestForwardListFromStdModule.py
  import-std-module/forward_list-dbg-info-content.TestDbgInfoContentForwardListFromStdModule.py
  import-std-module/list.TestListFromStdModule.py
  import-std-module/list-dbg-info-content.TestDbgInfoContentListFromStdModule.py
  import-std-module/queue.TestQueueFromStdModule.py
  import-std-module/stack.TestStackFromStdModule.py
  import-std-module/vector.TestVectorFromStdModule.py
  import-std-module/vector-bool.TestVectorBoolFromStdModule.py
  import-std-module/vector-dbg-info-content.TestDbgInfoContentVectorFromStdModule.py
  import-std-module/vector-of-vectors.TestVectorOfVectorsFromStdModule.py

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45301/
2022-07-13 09:20:30 -07:00
Matheus Izvekov bdc6974f92
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-13 02:10:09 +02:00
Nikita Popov 532dc62b90 [OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)
This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.

The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.

Differential Revision: https://reviews.llvm.org/D123115
2022-04-07 12:09:47 +02:00
hyeongyu kim 1b1c8d83d3 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2022-01-16 18:54:17 +09:00
James Y Knight fddc4e4116 Correct handling of the 'throw()' exception specifier in C++17.
Per C++17 [except.spec], 'throw()' has become equivalent to
'noexcept', and should therefore call std::terminate, not
std::unexpected.

Differential Revision: https://reviews.llvm.org/D113517
2021-11-10 17:40:16 -05:00
hyeongyu kim fd9b099906 Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit aacfbb953e.

Revert "Fix lit test failures in CodeGenCoroutines"

This reverts commit 63fff0f5bf.
2021-11-09 02:15:55 +09:00
hyeongyukim aacfbb953e [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453

Resolve lit failures in clang after 8ca4b3e's land

Fix lit test failures in clang-ppc* and clang-x64-windows-msvc

Fix missing failures in clang-ppc64be* and retry fixing clang-x64-windows-msvc

Fix internal_clone(aarch64) inline assembly
2021-11-06 19:19:22 +09:00
Juneyoung Lee 89ad2822af Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit 7584ef766a.
2021-11-06 15:39:19 +09:00
Juneyoung Lee 7584ef766a [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2021-11-06 15:36:42 +09:00
Juneyoung Lee f193bcc701 Revert D105169 due to the two-stage failure in ASAN
This reverts the following commits:
37ca7a795b
9aa6c72b92
705387c507
8ca4b3ef19
80dba72a66
2021-10-18 23:52:46 +09:00
Juneyoung Lee 8ca4b3ef19 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)
This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453
2021-10-16 12:01:41 +09:00
Corentin Jabot 3c8e94bc20 Disallow narrowing conversions to bool in noexcept specififers
Completes the support for P1401R5.
2021-08-06 10:26:39 -04:00
CJ Johnson 69cd776e1e [CodeGen] Apply 'nonnull' and 'dereferenceable(N)' to 'this' pointer
arguments.

* Adds 'nonnull' and 'dereferenceable(N)' to 'this' pointer arguments
* Gates 'nonnull' on -f(no-)delete-null-pointer-checks
* Introduces this-nonnull.cpp and microsoft-abi-this-nullable.cpp tests to
  explicitly test the behavior of this change
* Refactors hundreds of over-constrained clang tests to permit these
  attributes, where needed
* Updates Clang12 patch notes mentioning this change

Reviewed-by: rsmith, jdoerfert

Differential Revision: https://reviews.llvm.org/D17993
2020-11-16 17:39:17 -08:00
Richard Smith f7f2e4261a PR47805: Use a single object for a function parameter in the caller and
callee in constant evaluation.

We previously made a deep copy of function parameters of class type when
passing them, resulting in the destructor for the parameter applying to
the original argument value, ignoring any modifications made in the
function body. This also meant that the 'this' pointer of the function
parameter could be observed changing between the caller and the callee.

This change completely reimplements how we model function parameters
during constant evaluation. We now model them roughly as if they were
variables living in the caller, albeit with an artificially reduced
scope that covers only the duration of the function call, instead of
modeling them as temporaries in the caller that we partially "reparent"
into the callee at the point of the call. This brings some minor
diagnostic improvements, as well as significantly reduced stack usage
during constant evaluation.
2020-10-14 17:43:51 -07:00
Richard Smith 69f7c006ff Revert "PR47805: Use a single object for a function parameter in the caller and"
Breaks a clangd unit test.

This reverts commit 8f8b9f2cca.
2020-10-13 19:32:03 -07:00
Richard Smith 8f8b9f2cca PR47805: Use a single object for a function parameter in the caller and
callee in constant evaluation.

We previously made a deep copy of function parameters of class type when
passing them, resulting in the destructor for the parameter applying to
the original argument value, ignoring any modifications made in the
function body. This also meant that the 'this' pointer of the function
parameter could be observed changing between the caller and the callee.

This change completely reimplements how we model function parameters
during constant evaluation. We now model them roughly as if they were
variables living in the caller, albeit with an artificially reduced
scope that covers only the duration of the function call, instead of
modeling them as temporaries in the caller that we partially "reparent"
into the callee at the point of the call. This brings some minor
diagnostic improvements, as well as significantly reduced stack usage
during constant evaluation.
2020-10-13 18:50:46 -07:00
Richard Smith ab870f3030 Revert "PR47805: Use a single object for a function parameter in the caller and"
The buildbots are displeased.

This reverts commit 8d03a972ce.
2020-10-13 15:59:00 -07:00
Richard Smith 8d03a972ce PR47805: Use a single object for a function parameter in the caller and
callee in constant evaluation.

We previously made a deep copy of function parameters of class type when
passing them, resulting in the destructor for the parameter applying to
the original argument value, ignoring any modifications made in the
function body. This also meant that the 'this' pointer of the function
parameter could be observed changing between the caller and the callee.

This change completely reimplements how we model function parameters
during constant evaluation. We now model them roughly as if they were
variables living in the caller, albeit with an artificially reduced
scope that covers only the duration of the function call, instead of
modeling them as temporaries in the caller that we partially "reparent"
into the callee at the point of the call. This brings some minor
diagnostic improvements, as well as significantly reduced stack usage
during constant evaluation.
2020-10-13 15:45:04 -07:00
Eli Friedman 62f3ef2b53 [CGCall] Annotate references with "align" attribute.
If we're going to assume references are dereferenceable, we should also
assume they're aligned: otherwise, we can't actually dereference them.

See also D80072.

Differential Revision: https://reviews.llvm.org/D80166
2020-05-19 20:21:30 -07:00
Anastasia Stulova fa755d3e71 [Sema][C++] Propagate conversion kind to specialize the diagnostics
Compute and propagate conversion kind to diagnostics helper in C++
to provide more specific diagnostics about incorrect implicit
conversions in assignments, initializations, params, etc...

Duplicated some diagnostics as errors because C++ is more strict.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74116
2020-02-25 16:05:37 +00:00
Richard Smith 4a4e90a823 [c++20] Compute exception specifications for defaulted comparisons.
This requires us to essentially fully form the body of the defaulted
comparison, but from an unevaluated context. Naively this would require
generating the function definition twice; instead, we ensure that the
function body is implicitly defined before performing the check, and
walk the actual body where possible.
2019-12-15 22:02:31 -08:00
Tim Northover a009a60a91 IR: print value numbers for unnamed function arguments
For consistency with normal instructions and clarity when reading IR,
it's best to print the %0, %1, ... names of function arguments in
definitions.

Also modifies the parser to accept IR in that form for obvious reasons.

llvm-svn: 367755
2019-08-03 14:28:34 +00:00
Richard Smith 2b45b267da P1286R2: Remove restriction that the exception specification of a
defaulted special member matches the implicit exception specification.

llvm-svn: 360011
2019-05-06 05:04:56 +00:00
Sean Fertile d900dd0c23 Revert "[CodeGenCXX] Treat 'this' as noalias in constructors"
This reverts commit https://reviews.llvm.org/rL344150 which causes
MachineOutliner related failures on the ppc64le multistage buildbot.

llvm-svn: 344526
2018-10-15 15:43:00 +00:00
Anton Bikineev cc7e74753a [CodeGenCXX] Treat 'this' as noalias in constructors
This is currently a clang extension and a resolution
of the defect report in the C++ Standard.

Differential Revision: https://reviews.llvm.org/D46441

llvm-svn: 344150
2018-10-10 16:14:51 +00:00
Richard Smith b64764a30b PR38141: check whether noexcept-specifications are equivalent in redeclarations
llvm-svn: 336946
2018-07-12 21:11:25 +00:00
Erich Keane 883f22ef7e [Sema][Crash] Correctly handle an non-dependent noexcept expr in function template
It seems that all of the other templated cases are handled correctly,
however the function template case was not correctly handled. This
patch recovers from this condition by setting the function to noexcept
after diagnosing. Previously it simply set NoexceptExpr to null,
which caused an Assert when this was evaluated during substitution.

Differential Revision:https://reviews.llvm.org/D38700

llvm-svn: 315638
2017-10-12 23:01:53 +00:00
Erich Keane 7538b35cef Address comments that escaped D33333
Patch By: Jen Yu

Differential Revision:https://reviews.llvm.org/D34671

llvm-svn: 307172
2017-07-05 16:43:45 +00:00
Erich Keane 89fe9c269a Emit warning when throw exception in destruct or dealloc functions which has a
(possible implicit) noexcept specifier

Throwing in the destructor is not good (C++11 change try to not allow see below).
 But in reality, those codes are exist.
C++11 [class.dtor]p3:

A declaration of a destructor that does not have an exception-specification is 
implicitly considered to have the same exception specification as an implicit 
declaration.

With this change, the application worked before may now run into runtime 
termination. My goal here is to emit a warning to provide only possible info to 
where the code may need to be changed.

First there is no way, in compile time to identify the “throw” really throw out 
of the function. Things like the call which throw out… To keep this simple, 
when “throw” is seen, checking its enclosing function(only destructor and 
dealloc functions) with noexcept(true) specifier emit warning.

Here is implementation detail:
A new member function CheckCXXThrowInNonThrowingFunc is added for class Sema 
in Sema.h. It is used in the call to both BuildCXXThrow and 
TransformCXXThrowExpr.

The function basic check if the enclosing function with non-throwing noexcept 
specifer, if so emit warning for it.

The example of warning message like:
k1.cpp:18:3: warning: ''~dependent_warn'' has a (possible implicit) non-throwing

    noexcept specifier. Throwing exception may cause termination.
        [-Wthrow-in-dtor]
        throw 1;
        ^

        k1.cpp:43:30: note: in instantiation of member function

        'dependent_warn<noexcept_fun>::~dependent_warn' requested here

        dependent_warn<noexcept_fun> f; // cause warning

Differential Revision: https://reviews.llvm.org/D33333

llvm-svn: 306149
2017-06-23 20:22:19 +00:00
Richard Smith 3c4f8d2e96 P0012R1: Make exception specifications be part of the type system. This
implements the bulk of the change (modifying the type system to include
exception specifications), but not all the details just yet.

llvm-svn: 284337
2016-10-16 17:54:23 +00:00
Richard Smith e15a370084 PR25890: Fix incoherent error handling in PerformImplicitConversion and
CheckSingleAssignmentConstraints. These no longer produce ExprError() when they
have not emitted an error, and reliably inform the caller when they *have*
emitted an error.

This fixes some serious issues where we would fail to emit any diagnostic for
invalid code and then attempt to emit code for an invalid AST, and conversely
some issues where we would emit two diagnostics for the same problem.

llvm-svn: 283508
2016-10-06 23:12:58 +00:00
Richard Smith 5179eb7821 P0136R1, DR1573, DR1645, DR1715, DR1736, DR1903, DR1941, DR1959, DR1991:
Replace inheriting constructors implementation with new approach, voted into
C++ last year as a DR against C++11.

Instead of synthesizing a set of derived class constructors for each inherited
base class constructor, we make the constructors of the base class visible to
constructor lookup in the derived class, using the normal rules for
using-declarations.

For constructors, UsingShadowDecl now has a ConstructorUsingShadowDecl derived
class that tracks the requisite additional information. We create shadow
constructors (not found by name lookup) in the derived class to model the
actual initialization, and have a new expression node,
CXXInheritedCtorInitExpr, to model the initialization of a base class from such
a constructor. (This initialization is special because it performs real perfect
forwarding of arguments.)

In cases where argument forwarding is not possible (for inalloca calls,
variadic calls, and calls with callee parameter cleanup), the shadow inheriting
constructor is not emitted and instead we directly emit the initialization code
into the caller of the inherited constructor.

Note that this new model is not perfectly compatible with the old model in some
corner cases. In particular:
 * if B inherits a private constructor from A, and C uses that constructor to
   construct a B, then we previously required that A befriends B and B
   befriends C, but the new rules require A to befriend C directly, and
 * if a derived class has its own constructors (and so its implicit default
   constructor is suppressed), it may still inherit a default constructor from
   a base class

llvm-svn: 274049
2016-06-28 19:03:57 +00:00
Richard Smith a91de375f2 Promote a warning on ill-formed code (redeclaration missing an exception
specification) to an error. No compiler other than Clang seems to allow this,
and it doesn't seem like a useful thing to accept as an extension in general.

The current behavior was added for PR5957, where the problem was specifically
related to mismatches of the exception specification on the implicitly-declared
global operator new and delete. To retain that workaround, we downgrade the
error to an ExtWarn when the declaration is of a replaceable global allocation
function.

Now that this is an error, stop trying (and failing) to recover from a missing
computed noexcept specification. That recovery didn't work, and led to crashes
in code like the added testcase.

llvm-svn: 248867
2015-09-30 00:48:50 +00:00
David Majnemer fcbdb6ea58 Update clang to take into account the changes to personality fns
llvm-svn: 239941
2015-06-17 20:53:19 +00:00
Rafael Espindola e5df59ff78 Emit DeferredDeclsToEmit in a DFS order.
Currently we emit DeferredDeclsToEmit in reverse order. This patch changes that.

The advantages of the change are that

* The output order is a bit closer to the source order. The change to
test/CodeGenCXX/pod-member-memcpys.cpp is a good example.

* If we decide to deffer more, it will not cause as large changes in the
estcases as it would without this patch.

llvm-svn: 226751
2015-01-22 00:24:57 +00:00
Richard Smith 88f45490a0 Delay checking overrides for exception specifications if the overridden
specification has not yet been parsed.

llvm-svn: 222603
2014-11-22 03:09:05 +00:00
Richard Smith 2e32155b58 Instantiate exception specifications when instantiating function types (other
than the type of a function declaration). We previously didn't instantiate
these at all! This also covers the pathological case where the only mention of
a parameter pack is within the exception specification; this gives us a second
way (other than alias templates) to reach the horrible state where a type
contains an unexpanded pack, but its canonical type does not.


This is a re-commit of r219977:

r219977 was reverted in r220038 because it hit a wrong-code bug in GCC 4.7.2.
(That's gcc.gnu.org/PR56135, and affects any implicit lambda-capture of
'this' within a template.)


r219977 was a re-commit of r217995, r218011, and r218053:

r217995 was reverted in r218058 because it hit a rejects-valid bug in MSVC.
(Incorrect overload resolution in the presence of using-declarations.)
It was re-committed in r219977 with a workaround for the MSVC rejects-valid.

r218011 was a workaround for an MSVC parser bug. (Incorrect desugaring of
unbraced range-based for loop).

llvm-svn: 221750
2014-11-12 02:00:47 +00:00
NAKAMURA Takumi 23224155e1 Revert r219977, "Re-commit r217995 and follow-up patches (r217997, r218011, r218053). These were"
It broke some builders. I guess it'd be reproducible with --vg.

  Failing Tests (3):
      Clang :: CXX/except/except.spec/p1.cpp
      Clang :: SemaTemplate/instantiate-exception-spec-cxx11.cpp
      Clang :: SemaTemplate/instantiate-exception-spec.cpp

llvm-svn: 220038
2014-10-17 12:48:37 +00:00
Richard Smith 9c04bce1f1 Re-commit r217995 and follow-up patches (r217997, r218011, r218053). These were
reverted in r218058 because they triggered a rejects-valid bug in MSVC.

Original commit message from r217995:

Instantiate exception specifications when instantiating function types (other
than the type of a function declaration). We previously didn't instantiate
these at all! This also covers the pathological case where the only mention of
a parameter pack is within the exception specification; this gives us a second
way (other than alias templates) to reach the horrible state where a type
contains an unexpanded pack, but its canonical type does not.

llvm-svn: 219977
2014-10-16 23:00:46 +00:00
Hans Wennborg e113c20c1d Revert r217995 and follow-ups:
r218053: Use exceptions() instead of getNumExceptions()/getExceptionType() to avoid
r218011: Work around MSVC parser bug by putting redundant braces around the body of
r217997: Skip parens when detecting whether we're instantiating a function declaration.
r217995: Instantiate exception specifications when instantiating function types (other

The Windows build was broken for 16 hours and no one had any good ideas of how to
fix it. Reverting for now to make the builders green. See the cfe-commits thread [1] for
more info.

This was the build error (from [2]):

C:\bb-win7\ninja-clang-i686-msc17-R\llvm-project\clang\lib\Sema\SemaTemplateInstantiate.cpp(1590) : error C2668: '`anonymous-namespace'::TemplateInstantiator::TransformFunctionProtoType' : ambiguous call to overloaded function
        C:\bb-win7\ninja-clang-i686-msc17-R\llvm-project\clang\lib\Sema\SemaTemplateInstantiate.cpp(1313): could be 'clang::QualType `anonymous-namespace'::TemplateInstantiator::TransformFunctionProtoType<clang::Sema::SubstFunctionDeclType::<lambda_756edcbe7bd5c7584849a6e3a1491735>>(clang::TypeLocBuilder &,clang::FunctionProtoTypeLoc,clang::CXXRecordDecl *,unsigned int,Fn)'
        with
        [
            Fn=clang::Sema::SubstFunctionDeclType::<lambda_756edcbe7bd5c7584849a6e3a1491735>
        ]
        c:\bb-win7\ninja-clang-i686-msc17-r\llvm-project\clang\lib\sema\TreeTransform.h(4532): or       'clang::QualType clang::TreeTransform<Derived>::TransformFunctionProtoType<clang::Sema::SubstFunctionDeclType::<lambda_756edcbe7bd5c7584849a6e3a1491735>>(clang::TypeLocBuilder &,clang::FunctionProtoTypeLoc,clang::CXXRecordDecl *,unsigned int,Fn)'
        with
        [
            Derived=`anonymous-namespace'::TemplateInstantiator,
            Fn=clang::Sema::SubstFunctionDeclType::<lambda_756edcbe7bd5c7584849a6e3a1491735>
        ]
        while trying to match the argument list '(clang::TypeLocBuilder, clang::FunctionProtoTypeLoc, clang::CXXRecordDecl *, unsigned int, clang::Sema::SubstFunctionDeclType::<lambda_756edcbe7bd5c7584849a6e3a1491735>)'

 1. http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20140915/115011.html
 2. http://bb.pgr.jp/builders/ninja-clang-i686-msc17-R/builds/10515/steps/build_clang_tools_1/logs/stdio

llvm-svn: 218058
2014-09-18 16:01:32 +00:00
Richard Smith 4ff123860b Instantiate exception specifications when instantiating function types (other
than the type of a function declaration). We previously didn't instantiate
these at all! This also covers the pathological case where the only mention of
a parameter pack is within the exception specification; this gives us a second
way (other than alias templates) to reach the horrible state where a type
contains an unexpanded pack, but its canonical type does not.

llvm-svn: 217995
2014-09-17 23:57:05 +00:00
Hal Finkel a2347baaec Mark C++ reference parameters as dereferenceable
Because references must be initialized using some evaluated expression, they
must point to something, and a callee can assume the reference parameter is
dereferenceable. Taking advantage of a new attribute just added to LLVM, mark
them as such.

Because dereferenceability in addrspace(0) implies nonnull in the backend, we
don't need both attributes. However, we need to know the size of the object to
use the dereferenceable attribute, so for incomplete types we still emit only
nonnull.

llvm-svn: 213386
2014-07-18 15:52:10 +00:00
Nick Lewycky 9b46eb8112 Add 'nonnull' parameter or return attribute when producing an llvm pointer type in a function type where the C++ type is a reference. Update the tests.
llvm-svn: 209723
2014-05-28 09:56:42 +00:00
Eric Christopher c9e2a68905 Clean up language and grammar.
Based on a patch by jfcaron3@gmail.com!
PR19806

llvm-svn: 209215
2014-05-20 17:10:39 +00:00
Richard Smith c7fb225cdc PR16638, DR1552: the exception specification on an implicitly-declared
'operator delete' or 'operator delete[]' is an explicit exception
specification. Therefore we should diagnose 'void operator delete(void*)'
instead of 'void operator delete(void*) noexcept'.

This diagnostic remains an ExtWarn, since in practice people don't always
include the exception specification in such a declaration.

llvm-svn: 201002
2014-02-07 22:51:16 +00:00
Alp Toker 73287bfe40 MSVC 2013 type trait support
Implement type trait primitives used in the latest edition of the Microsoft
standard C++ library type_traits header.

With this change we can parse much of the Visual Studio 2013 standard headers,
particularly anything that includes <type_traits>.

Fully implemented, available in all language modes:

 * __is_constructible()
 * __is_nothrow_constructible()
 * __is_nothrow_assignable()

Partially implemented, semantic analysis WIP, available as MS extensions:

 * __is_destructible()
 * __is_nothrow_destructible()

llvm-svn: 199619
2014-01-20 00:24:09 +00:00
Richard Smith c91d12ce80 Take cv-qualifiers on fields of class type into account when determining
whether a defaulted special member function should be deleted.

llvm-svn: 195620
2013-11-25 07:07:05 +00:00