39 Commits

Author SHA1 Message Date
Timm Bäder
a038f9758e [clang][Interp] Fix virtual calls with reference instance pointers
getCXXRecordType() on those types does not return the type we need.
Use getPointeeCXXRecordType() instead in those cases.
2024-03-01 16:19:45 +01:00
Aaron Ballman
0f1c1be196 [clang] Remove rdar links; NFC
We have a new policy in place making links to private resources
something we try to avoid in source and test files. Normally, we'd
organically switch to the new policy rather than make a sweeping change
across a project. However, Clang is in a somewhat special circumstance
currently: recently, I've had several new contributors run into rdar
links around test code which their patch was changing the behavior of.
This turns out to be a surprisingly bad experience, especially for
newer folks, for a handful of reasons: not understanding what the link
is and feeling intimidated by it, wondering whether their changes are
actually breaking something important to a downstream in some way,
having to hunt down strangers not involved with the patch to impose on
them for help, accidental pressure from asking for potentially private
IP to be made public, etc. Because folks run into these links entirely
by chance (through fixing bugs or working on new features), there's not
really a set of problematic links to focus on -- all of the links have
basically the same potential for causing these problems. As a result,
this is an omnibus patch to remove all such links.

This was not a mechanical change; it was done by manually searching for
rdar, radar, radr, and other variants to find all the various
problematic links. From there, I tried to retain or reword the
surrounding comments so that we would lose as little context as
possible. However, because most links were just a plain link with no
supporting context, the majority of the changes are simple removals.

Differential Review: https://reviews.llvm.org/D158071
2023-08-28 12:13:42 -04:00
Mehdi Amini
e0ac46e69d Revert "Remove rdar links; NFC"
This reverts commit d618f1c3b12effd0c2bdb7d02108d3551f389d3d.
This commit wasn't reviewed ahead of time and significant concerns were
raised immediately after it landed. According to our developer policy
this warrants immediate revert of the commit.

https://llvm.org/docs/DeveloperPolicy.html#patch-reversion-policy

Differential Revision: https://reviews.llvm.org/D155509
2023-07-17 18:08:04 -07:00
Aaron Ballman
d618f1c3b1 Remove rdar links; NFC
This removes links to rdar, which is an internal bug tracker that the
community doesn't have visibility into.

See further discussion at:
https://discourse.llvm.org/t/code-review-reminder-about-links-in-code-commit-messages/71847
2023-07-07 08:41:11 -04:00
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 7c51f02effdbd0d5e12bfd26f9c3b2ab5687c93f 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 bdc6974f92304f4ed542241b9b89ba58ba6b20aa 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
Richard Smith
7ae1b4a0ce Implement P1766R1: diagnose giving non-C-compatible classes a typedef name for linkage purposes.
Summary:
Due to a recent (but retroactive) C++ rule change, only sufficiently
C-compatible classes are permitted to be given a typedef name for
linkage purposes. Add an enabled-by-default warning for these cases, and
rephrase our existing error for the case where we encounter the typedef
name for linkage after we've already computed and used a wrong linkage
in terms of the new rule.

Reviewers: rjmccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74103
2020-02-07 11:47:37 -08:00
Richard Smith
df963a38a9 DR1113: anonymous namespaces formally give their contents internal linkage.
This doesn't affect our code generation in any material way -- we already give
such declarations internal linkage from a codegen perspective -- but it has
some subtle effects on code validity.

We suppress the 'L' (internal linkage) marker for mangled names in anonymous
namespaces, because it is redundant (the information is already carried by the
namespace); this deviates from GCC's behavior if a variable or function in an
anonymous namespace is redundantly declared 'static' (where GCC does include
the 'L'), but GCC's behavior is incoherent because such a declaration can be
validly declared with or without the 'static'.

We still deviate from the standard in one regard here: extern "C" declarations
in anonymous namespaces are still granted external linkage. Changing those does
not appear to have been an intentional consequence of the standard change in
DR1113.

llvm-svn: 314037
2017-09-22 22:21:44 +00:00
Richard Smith
e5945871cf Revisit PR10177: don't instantiate a variable if it's only referenced in a
dependent context and can't be used in a constant expression.

Per C++ [temp.inst]p2, "the instantiation of a static data member does not
occur unless the static data member is used in a way that requires the
definition to exist".

This doesn't /quite/ match that, as we still instantiate static data members
that are usable in constant expressions even if the use doesn't require a
definition. A followup patch will fix that for both variables and functions.

llvm-svn: 291295
2017-01-06 22:52:53 +00:00
Serge Pavlov
7dcc97e7ac Warn if function or variable cannot be implicitly instantiated
With this patch compiler emits warning if it tries to make implicit instantiation
of a template but cannot find the template definition. The warning can be suppressed
by explicit instantiation declaration or by command line options
-Wundefined-var-template and -Wundefined-func-template. The implementation follows
the discussion of http://reviews.llvm.org/D12326.

Differential Revision: http://reviews.llvm.org/D16396

llvm-svn: 266719
2016-04-19 06:19:52 +00:00
Charles Li
542f04cc4d [Lit Test] Updated 26 Lit tests to be C++11 compatible.
Expected diagnostics have been expanded to vary by C++ dialect.
RUN line has also been expanded to: default, C++98/03 and C++11.

llvm-svn: 252785
2015-11-11 19:34:47 +00:00
Aaron Ballman
6c93b3e29c Adding a -Wunused-value warning for expressions with side effects used in an unevaluated expression context, such as sizeof(), or decltype(). Also adds a similar warning when the expression passed to typeid() *is* evaluated, since it is equally likely that the user would expect the expression operand to be unevaluated in that case.
llvm-svn: 224465
2014-12-17 21:57:17 +00:00
Nico Weber
acb35c0272 Change -Wbind-to-temporary-copy from an ExtWarn to an Extension.
The reasoning is that this construct is accepted by all compilers and valid in
C++11, so it doesn't seem like a useful warning to have enabled by default.
Building with -pedantic, -Wbind-to-temporary-copy, or -Wc++98-compat still
shows the warning.

The motivation is that I built re2, and this was the only warning that was
emitted during the build. Both changing re2 to fix the warning and detecting
clang and suppressing the warning in re2's build seem inferior than just giving
the compiler a good default for this warning.

Also move the cxx98compat version of this warning to CXX98CompatPedantic, and
update tests accordingly.

llvm-svn: 218008
2014-09-18 02:09:53 +00:00
Hans Wennborg
80fb253fa7 test/SemaCXX/undefined-internal.cpp: Remove target triple.
This test seems to run fine in both MS and Itanium C++ ABI mode these days.

llvm-svn: 210357
2014-06-06 17:51:25 +00:00
Alp Toker
7f02e53f5a Revert "Fix the undefined-but-used odr-use marker (DR48)"
Wrong patch got committed (this one isn't ready for prime time).

This reverts commit r209996.

llvm-svn: 209997
2014-06-01 19:13:44 +00:00
Alp Toker
71c53d472f Fix the undefined-but-used odr-use marker (DR48)
We should treat tentative definitions as undefined for the purpose of
ODR-use linkage checking.

This broke somewhere around r149731 when tests were disabled.

Note that test coverage for these diagnostics is generally lacking due to a
separate issue (PR19910: Don't suppress unused/undefined warnings when there
are errors).

llvm-svn: 209996
2014-06-01 18:49:32 +00:00
David Blaikie
abe1a398e3 Render anonymous entities as '(anonymous <thing>)' (and lambdas as '(lambda at ... )')
For namespaces, this is consistent with mangling and GCC's debug info
behavior. For structs, GCC uses <anonymous struct> but we prefer
consistency between all anonymous entities but don't want to confuse
them with template arguments, etc, so we'll just go with parens in all
cases.

llvm-svn: 205398
2014-04-02 05:58:29 +00:00
David Blaikie
8972f4e966 Consistently print anonymous namespace names as "<anonymous namespace>"
For some reason we have two bits of code handling this printing:

lib/AST/Decl.cpp:        OS << "<anonymous namespace>";
lib/AST/TypePrinter.cpp:      OS << "<anonymous namespace>::";

it would be nice if we only had one...

llvm-svn: 201437
2014-02-14 22:12:54 +00:00
Richard Smith
e81daee21b When formatting a C++-only declaration name, enable C++ mode in the formatter's
language options. This is not really ideal -- we should require the right
language options to be passed in, or not require language options to format a
name -- but it fixes a number of *obviously* wrong formattings. Patch by
Olivier Goffart!

llvm-svn: 199778
2014-01-22 00:27:42 +00:00
Hans Wennborg
c9bd88e681 Remove the -cxx-abi command-line flag.
This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be able to run a test with a specific ABI without constraining it to a
specific triple, new substitutions are added to lit: %itanium_abi_triple and
%ms_abi_triple can be used to get the current target triple adjusted to the
desired ABI. For example, if the test suite is running with the i686-pc-win32
target, %itanium_abi_triple will expand to i686-pc-mingw32.

Differential Revision: http://llvm-reviews.chandlerc.com/D2545

llvm-svn: 199250
2014-01-14 19:35:09 +00:00
Hans Wennborg
9125b08b52 Update tests in preparation for using the MS ABI for Win32 targets
In preparation for making the Win32 triple imply MS ABI mode,
make all tests pass in this mode, or make them use the Itanium
mode explicitly.

Differential Revision: http://llvm-reviews.chandlerc.com/D2401

llvm-svn: 199130
2014-01-13 19:48:13 +00:00
Rafael Espindola
327be3cc20 Add r180263 back, but fix hasBraces() to be correct during parsing.
Original commit message:

Fix a case in linkage computation that should check for single line extern "C".

llvm-svn: 180591
2013-04-26 01:30:23 +00:00
Bill Wendling
afddaa4719 Revert r180263. It's causing failures.
llvm-svn: 180583
2013-04-25 23:15:02 +00:00
Rafael Espindola
7e2e4fafc0 Fix a case in linkage computation that should check for single line extern "C".
llvm-svn: 180263
2013-04-25 13:10:46 +00:00
Nick Lewycky
b7444cd11e When marking derived classes' virtual methods ODR-used in order to trigger
instantiation in order to permit devirtualization later in codegen, skip over
pure functions since those can't be devirtualization targets.

llvm-svn: 175116
2013-02-14 00:55:17 +00:00
Nick Lewycky
a096b14d1d The meat of this patch is in BuildCXXMemberCalLExpr where we make it use
MarkMemberReferenced instead of marking functions referenced directly. An audit
of callers to MarkFunctionReferenced and DiagnoseUseOfDecl also caused a few
other changes:
 * don't mark functions odr-used when considering them for an initialization
   sequence. Do mark them referenced though.
 * the function nominated by the cleanup attribute should be diagnosed.
 * operator new/delete should be diagnosed when building a 'new' expression.

llvm-svn: 174951
2013-02-12 08:08:54 +00:00
Nick Lewycky
134af91b06 Apply the pure-virtual odr rule to other constructs which can call overloaded
operators.

llvm-svn: 174584
2013-02-07 05:08:22 +00:00
Nick Lewycky
45b5052834 This patch makes "&Cls::purevfn" not an odr use. This isn't what the standard
says, but that's a defect (to be filed). "Cls::purevfn()" is still an odr use.

Also fixes a bug that caused us to not mark the function referenced just
because we didn't want to mark it odr used.

llvm-svn: 174242
2013-02-02 00:25:55 +00:00
Nick Lewycky
35d2359b1c Fix ODR-use of a MemberExpr to check before marking a pure function used. Remove
a workaround for this bug from the -Wundefined-internals warning.

llvm-svn: 174020
2013-01-31 01:34:31 +00:00
Rafael Espindola
9463dce9bf Don't warn for undefined but used decls that are external because of a typedef.
This fixes pr14736. It is fairly ugly, but I don't think we can do much better
as we have to wait at least until the end of the typedef to know if the
function will have external linkage or not.

llvm-svn: 171240
2012-12-29 23:43:00 +00:00
Eli Friedman
77dcc726de Make sure template argument deduction is consistently performed in an unevaluated context.
llvm-svn: 150049
2012-02-08 03:07:05 +00:00
Eli Friedman
130bbd0302 Suppress the used-but-not-defined warning for static data members while I look into a rather nasty bug in the new odr-use marking code.
llvm-svn: 149731
2012-02-04 00:54:05 +00:00
Eli Friedman
3bda6b1f8e Add some code to accurately perform odr-used marking for variables per the C++11 rules.
llvm-svn: 149641
2012-02-02 23:15:15 +00:00
Chandler Carruth
a28097da4f Rough fix for PR9323 that prevents Clang from marking copy constructor
declarations as referenced when in fact we're not going to even form
a call in the AST. This is significant because we attempt to allow as an
extension classes with intentionally private and undefined copy
constructors to have temporaries bound to references, and so shouldn't
warn about the lack of definition for that copy constructor when the
class is internal.

Doug, John wasn't really satisfied with the presence of overloading at
all. This is a stop-gap and there may be a better solution. If you can
give me some hints for how you'd prefer to see this solved, I'll happily
switch things over.

llvm-svn: 126480
2011-02-25 08:52:25 +00:00
John McCall
15dd404c46 Don't warn about static const integral data members with in-line constant
initializers just because they don't have a proper out-of-line definition.
Such code is technically ill-formed but is too common and too unlikely to be
a problem to be seriously worth worrying about.

llvm-svn: 126137
2011-02-21 19:25:48 +00:00
John McCall
8377967543 Warn about code that uses variables and functions with internal linkage
without defining them.  This should be an error, but I'm paranoid about
"uses" that end up not actually requiring a definition.  I'll revisit later.

Also, teach IR generation to not set internal linkage on variable
declarations, just for safety's sake.  Doing so produces an invalid module
if the variable is not ultimately defined.

Also, fix several places in the test suite where we were using internal
functions without definitions.

llvm-svn: 126016
2011-02-19 02:53:41 +00:00