Commit Graph

38 Commits

Author SHA1 Message Date
Shafik Yaghmour aa7ce60536 [Clang] Avoid crashes when parsing using enum declarations
In Parser::ParseUsingDeclaration(...) when we call ParseEnumSpecifier(...) it is
not calling SetTypeSpecError() on DS when it detects an error. That means that
DS is left set to TST_unspecified. When we then pass DS into
Sema::ActOnUsingEnumDeclaration(...) we hit an llvm_unreachable(...) since it
expects it to be one of three states TST_error, TST_enum or TST_typename.

This fixes https://github.com/llvm/llvm-project/issues/57347

Differential Revision: https://reviews.llvm.org/D132695
2022-08-27 15:18:36 -07:00
Shafik Yaghmour b364535304 [Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values
DR2338 clarified that it was undefined behavior to set the value outside the
range of the enumerations values for an enum without a fixed underlying type.

We should diagnose this with a constant expression context.

Differential Revision: https://reviews.llvm.org/D130058
2022-07-28 15:27:50 -07:00
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 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
Akira Hatanaka 66e08995b0 [Sema] Reject list-initialization of enumeration types from a
brace-init-list containing a single element of a different scoped
enumeration type

It is rejected because it doesn't satisfy the condition that the element
has to be implicitly convertible to the underlying type of the
enumeration.

http://eel.is/c++draft/dcl.init.list#3.8

Differential Revision: https://reviews.llvm.org/D126084
2022-06-02 17:25:11 -07:00
Nathan Sidwell 012898b92c [clang] p1099 using enum part 1
This adds support for p1099's 'using SCOPED_ENUM::MEMBER;'
functionality, bringing a member of an enumerator into the current
scope. The novel feature here, is that there need not be a class
hierarchical relationship between the current scope and the scope of
the SCOPED_ENUM. That's a new thing, the closest equivalent is a
typedef or alias declaration. But this means that
Sema::CheckUsingDeclQualifier needs adjustment. (a) one can't call it
until one knows the set of decls that are being referenced -- if
exactly one is an enumerator, we're in the new territory. Thus it
needs calling later in some cases. Also (b) there are two ways we hold
the set of such decls. During parsing (or instantiating a dependent
scope) we have a lookup result, and during instantiation we have a set
of shadow decls. Thus two optional arguments, at most one of which
should be non-null.

Differential Revision: https://reviews.llvm.org/D100276
2021-06-08 04:40:42 -07:00
Richard Smith d6425e2c14 Properly implement 'enum class' parsing.
The 'class' or 'struct' keyword is only permitted as part of either an
enum definition or a standalone opaque-enum-declaration, not as part of
an elaborated type specifier. We previously failed to diagnose this, and
generally didn't properly implement the restrictions on elaborated type
specifiers for enumeration types.

In passing, also fixed incorrect parsing for enum-bases, which we
previously parsed as a type-name, but are actually a type-specifier-seq.
This matters for cases like 'enum E : int *p;', which is valid as a
Microsoft extension.

Plus some minor parse diagnostic improvements.

Bumped the recently-added ExtWarn for 'enum E : int x;' to be
DefaultError; this is not an intentional extension, so producing an
error by default seems appropriate, but the warning flag to disable it
may still be useful for code written against old Clang. The same
treatment is given here to the diagnostic for 'enum class E x;', which
we similarly have incorrectly accepted for many years. These diagnostics
continue to be suppressed under -fms-extensions and when compiling
Objective-C code. We will need to decide separately whether Objective-C
should follow the C++ rules or the (older) MSVC rules.
2020-05-10 13:21:04 -07:00
Richard Smith c90e198107 Fix parsing of enum-base to follow C++11 rules.
Previously we implemented non-standard disambiguation rules to
distinguish an enum-base from a bit-field but otherwise treated a :
after an elaborated-enum-specifier as introducing an enum-base. That
misparses various examples (anywhere an elaborated-type-specifier can
appear followed by a colon, such as within a ternary operator or
_Generic).

We now implement the C++11 rules, with the old cases accepted as
extensions where that seemed reasonable. These amount to:
 * an enum-base must always be accompanied by an enum definition (except
   in a standalone declaration of the form 'enum E : T;')
 * in a member-declaration, 'enum E :' always introduces an enum-base,
   never a bit-field
 * in a type-specifier (or similar context), 'enum E :' is not
   permitted; the colon means whatever else it would mean in that
   context.

Fixed underlying types for enums are also permitted in Objective-C and
under MS extensions, plus as a language extension in all other modes.
The behavior in ObjC and MS extensions modes is unchanged (but the
bit-field disambiguation is a bit better); remaining language modes
follow the C++11 rules.

Fixes PR45726, PR39979, PR19810, PR44941, and most of PR24297, plus C++
core issues 1514 and 1966.
2020-05-08 19:32:00 -07:00
Erich Keane bf5fad86db PR35586: Relax two asserts that are overly restrictive
The two asserts are too aggressive.  In C++  mode, an
enum is NOT considered an integral type, but an enum value
is allowed to be an enum.  This patch relaxes the two asserts
to allow the enum value as well (as typechecking does).

llvm-svn: 320411
2017-12-11 19:44:28 +00:00
Alex Lorenz 76377dcf99 Print nested name specifiers for typedefs and type aliases
Printing typedefs or type aliases using clang_getTypeSpelling() is missing the
namespace they are defined in. This is in contrast to other types that always
yield the full typename including namespaces.

Patch by Michael Reiher!

Differential Revision: https://reviews.llvm.org/D29944

llvm-svn: 297465
2017-03-10 15:04:58 +00:00
Richard Smith 5cbeb75a99 Fix implementation of C++'s restrictions on using-declarations referring to enumerators:
* an unscoped enumerator whose enumeration is a class member is itself a class
   member, so can only be the subject of a class-scope using-declaration.

 * a scoped enumerator cannot be the subject of a class-scope using-declaration.

llvm-svn: 268594
2016-05-05 02:13:49 +00:00
Richard Smith 43d3f55072 Look through sugar when determining whether a type is a scoped enumeration
type. Patch by Stephan Bergmann!

llvm-svn: 225889
2015-01-14 00:33:10 +00:00
Alp Toker c620cab8c4 PR18551: accepts invalid strong enum to bool when operator! is used
llvm-svn: 199627
2014-01-20 07:20:22 +00:00
Alp Toker 8c44db50d6 Diagnose enum redeclarations properly
In all three checks, the note indicates a previous declaration and never a 'use'.

Before:

  enum-scoped.cpp:92:6: note: previous use is here
    enum Redeclare6 : int;
         ^

After:

  enum-scoped.cpp:92:6: note: previous declaration is here
    enum Redeclare6 : int;
         ^

llvm-svn: 198600
2014-01-06 11:31:06 +00:00
Richard Smith 8ac1c92df9 PR18044: Reject declarations of enumtype::X early to avoid an assertion in
downstream code.

llvm-svn: 195687
2013-11-25 21:30:29 +00:00
Richard Smith e952106164 Correctly skip type sugar when determining the width of an enum type. Derived
from a patch by Justin Bogner.

llvm-svn: 192671
2013-10-15 04:56:17 +00:00
Eli Friedman 9ee175d8f0 Don't allow unary negation on scoped enums.
PR16900.

llvm-svn: 188511
2013-08-16 00:09:18 +00:00
Richard Smith 1d4b2e16a2 PR15633: Note that we are EnteringContext when parsing the nested name
specifier for an enumeration. Also fix a crash-on-invalid if a non-dependent
name specifier is used to declare an enum template.

llvm-svn: 178502
2013-04-01 21:43:41 +00:00
Aaron Ballman 24a1047c8c Relaxed enumeration constant naming rules for scoped enumerators so they no longer emit a diagnostic when the enumeration's name matches that of the class. Fixes PR13128.
llvm-svn: 160490
2012-07-19 03:12:23 +00:00
Richard Smith 2e6610affd Handle instantiations of redeclarations of forward-declared enumerations within
templated functions. Build a redeclaration chain, and only instantiate the
definition of the enum when visiting the defining declaration.

llvm-svn: 153427
2012-03-26 04:58:10 +00:00
Richard Smith 258a744bbd Delay checking of dependent underlying types for redeclarations of member
enumerations in templates until the template is instantiated.

llvm-svn: 153426
2012-03-26 04:08:46 +00:00
Richard Smith b66d77793f When defining a forward-declared enum, don't try to attach the definition to
a previous declaration if the redeclaration is invalid. That way lies madness.
Fixes a crash-on-invalid reported by Abramo.

llvm-svn: 153349
2012-03-23 23:09:08 +00:00
Nick Lewycky f604212a44 Slightly tweak this condition. "isTransparentContext()" was checking whether an
enum is scoped or not, which is not relevant here. Instead, phrase the loop in
the same terms that the standard uses, instead of this awkward set of
conditions that is *nearly* equal.

llvm-svn: 152489
2012-03-10 07:47:07 +00:00
Douglas Gregor 3f28ec28d5 Loosen the precondition of isCXXInstanceMember() to simply return
"false" for declarations that aren't members of classes. Fixes PR12106.

llvm-svn: 152284
2012-03-08 02:08:05 +00:00
Richard Smith 8dd3425077 Don't allow a value of a scoped enumeration to be used as the first bound for an
array new expression. This lays some groundwork for the implicit conversion to
integral or unscoped enumeration which C++11 ICEs undergo.

llvm-svn: 149772
2012-02-04 07:07:42 +00:00
Richard Smith f8379a0fc3 constexpr: converted constant expression handling for enumerator values, case
values and non-type template arguments of integral and enumeration types.

This change causes some legal C++98 code to no longer compile in C++11 mode, by
enforcing the C++11 rule that narrowing integral conversions are not permitted
in the final implicit conversion sequence for the above cases.

llvm-svn: 148439
2012-01-18 23:55:52 +00:00
Richard Smith 0f8ee22655 Update C++11 scoped enumeration support to match the final proposal:
- reject definitions of enums within friend declarations
 - require 'enum', not 'enum class', for non-declaring references to scoped
   enumerations

llvm-svn: 147824
2012-01-10 01:33:14 +00:00
Eli Friedman 7c6515a653 Make sure we perform lvalue-to-rvalue conversions for enum initializers. PR11484.
llvm-svn: 145874
2011-12-06 00:10:34 +00:00
Richard Smith 9ca5c42582 Update all tests other than Driver/std.cpp to use -std=c++11 rather than
-std=c++0x. Patch by Ahmed Charles!

llvm-svn: 141900
2011-10-13 22:29:44 +00:00
John McCall 21878760a4 Fixed enum types can be complete without actually being valid to use
as scope specifiers;  diagnose the attempt, rather than letting it go
to an assert.  The rest of PR10264.

llvm-svn: 134479
2011-07-06 06:57:57 +00:00
John McCall cb432faf6d Properly protect colons when parsing a nested-name-specifier as part
of an enum specifier in dialects which permit fixed underlying types.
Fixes the rejects-valid part of PR10264.

llvm-svn: 134468
2011-07-06 05:58:41 +00:00
Douglas Gregor 21673c4e7e Scoped enumerations should not be treated as integer types (in the C
sense). Fixes <rdar://problem/9366066> by eliminating an inconsistency
between C++ overloading (which handled scoped enumerations correctly)
and C binary operator type-checking (which didn't).

llvm-svn: 130924
2011-05-05 16:13:52 +00:00
Douglas Gregor 48e6bbffa1 Implement comparison of C++0x scoped enumeration types. Fixes PR9333.
llvm-svn: 126752
2011-03-01 17:16:20 +00:00
Douglas Gregor 6cd5ae4dfa Fix a little bug in the handling of enumeration types with a fixed
underlying type: we weren't parsing unnamed enumeration types with a
fixed underlying type.

llvm-svn: 126184
2011-02-22 02:55:24 +00:00
Douglas Gregor 0bf3140424 Implement C++0x scoped enumerations, from Daniel Wallin! (and tweaked a
bit by me). 

llvm-svn: 116122
2010-10-08 23:50:27 +00:00