Summary:
this revision adds Lexing, Parsing and Basic Semantic for the consteval specifier as specified by http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1073r3.html
with this patch, the consteval specifier is treated as constexpr but can only be applied to function declaration.
Changes:
- add the consteval keyword.
- add parsing of consteval specifier for normal declarations and lambdas expressions.
- add the whether a declaration is constexpr is now represented by and enum everywhere except for variable because they can't be consteval.
- adapt diagnostic about constexpr to print constexpr or consteval depending on the case.
- add tests for basic semantic.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: eraman, efriedma, rnkovacs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61790
llvm-svn: 363362
This caused Clang to start erroring on the following:
struct S {
template <typename = int> explicit S();
};
struct T : S {};
struct U : T {
U();
};
U::U() {}
$ clang -c /tmp/x.cc
/tmp/x.cc:10:4: error: call to implicitly-deleted default constructor of 'T'
U::U() {}
^
/tmp/x.cc:5:12: note: default constructor of 'T' is implicitly deleted
because base class 'S' has no default constructor
struct T : S {};
^
1 error generated.
See discussion on the cfe-commits email thread.
This also reverts the follow-ups r359966 and r359968.
> this patch adds support for the explicit bool specifier.
>
> Changes:
> - The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
> - The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
> - Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
> - Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
> - The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
> - Test for Semantic and Serialization were added.
>
> This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
> Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
>
> Patch by Tyker
>
> Differential Revision: https://reviews.llvm.org/D60934
llvm-svn: 360024
this patch adds support for the explicit bool specifier.
Changes:
- The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
- The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
- Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
- Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
- The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
- Test for Semantic and Serialization were added.
This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
Patch by Tyker
Differential Revision: https://reviews.llvm.org/D60934
llvm-svn: 359949
This unfortunately results in a substantial breaking change when
switching to C++20, but it's not yet clear what / how much we should
do about that. We may want to add a compatibility conversion from
u8 string literals to const char*, similar to how C++98 provided a
compatibility conversion from string literals to non-const char*,
but that's not handled by this patch.
The feature can be disabled in C++20 mode with -fno-char8_t.
llvm-svn: 346892