forked from OSchip/llvm-project
5030928d60
initializers.
This has some interesting interactions with our existing extensions to
support C99 designated initializers as an extension in C++. Those are
resolved as follows:
* We continue to permit the full breadth of C99 designated initializers
in C++, with the exception that we disallow a partial overwrite of an
initializer with a non-trivially-destructible type. (Full overwrite
is OK, because we won't run the first initializer at all.)
* The C99 extensions are disallowed in SFINAE contexts and during
overload resolution, where they could change the meaning of valid
programs.
* C++20 disallows reordering of initializers. We only check for that for
the simple cases that the C++20 rules permit (designators of the form
'.field_name =' and continue to allow reordering in other cases).
It would be nice to improve this behavior in future.
* All C99 designated initializer extensions produce a warning by
default in C++20 mode. People are going to learn the C++ rules based
on what Clang diagnoses, so it's important we diagnose these properly
by default.
* In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and
so still diagnose C99 extensions as described above. We continue to
accept designated C++20-compatible initializers in C++ <= 17 silently
by default (but naturally still reject under -pedantic-errors).
This is not a complete implementation of P0329R4. In particular, that
paper introduces new non-C99-compatible syntax { .field { init } }, and
we do not support that yet.
This is based on a previous patch by Don Hinton, though I've made
substantial changes when addressing the above interactions.
Differential Revision: https://reviews.llvm.org/D59754
llvm-svn: 370544
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| .. | ||
| Inputs | ||
| 2007-10-03-MetadataPointers.mm | ||
| 2010-08-04-Template.mm | ||
| 2010-08-06-X.Y-syntax.mm | ||
| address-safety-attr.mm | ||
| arc-attrs-abi.mm | ||
| arc-attrs.mm | ||
| arc-blocks.mm | ||
| arc-constexpr.mm | ||
| arc-cxx11-init-list.mm | ||
| arc-cxx11-member-init.mm | ||
| arc-exceptions.mm | ||
| arc-forwarded-lambda-call.mm | ||
| arc-globals.mm | ||
| arc-indirect.mm | ||
| arc-list-init-destruct.mm | ||
| arc-mangle.mm | ||
| arc-marker-funclet.mm | ||
| arc-move.mm | ||
| arc-new-delete.mm | ||
| arc-pseudo-destructors.mm | ||
| arc-references.mm | ||
| arc-returns-inner-reference-ptr.mm | ||
| arc-special-member-functions.mm | ||
| arc-weak.mm | ||
| arc.mm | ||
| auto-release-result-assert.mm | ||
| block-default-arg.mm | ||
| block-id.mm | ||
| block-in-template-inst.mm | ||
| block-nested-in-lambda.mm | ||
| block-var-layout.mm | ||
| blocks.mm | ||
| boxing.mm | ||
| catch-id-type.mm | ||
| copy.mm | ||
| copyable-property-object.mm | ||
| crash-function-type.mm | ||
| debug-info-block-capture-this.mm | ||
| debug-info-cyclic.mm | ||
| debug-info-line.mm | ||
| debug-info.mm | ||
| designated-initializers.mm | ||
| destroy.mm | ||
| encode.mm | ||
| exception-cxx.mm | ||
| exceptions-legacy.mm | ||
| exceptions.mm | ||
| externally-initialized-selectors.mm | ||
| foreach-statement.mm | ||
| gc.mm | ||
| implementation-in-extern-c.mm | ||
| implicit-copy-assign-operator.mm | ||
| implicit-copy-constructor.mm | ||
| inheriting-constructor-cleanup.mm | ||
| instantiate-return.mm | ||
| ivar-objects.mm | ||
| lambda-expressions.mm | ||
| lambda-to-block.mm | ||
| literals.mm | ||
| lvalue-reference-getter.mm | ||
| mangle-blocks.mm | ||
| mangle.mm | ||
| message-reference.mm | ||
| message.mm | ||
| method-local-extern-mangle.mm | ||
| microsoft-abi-arc-param-order.mm | ||
| mrc-weak.mm | ||
| msabi-objc-extensions.mm | ||
| msabi-objc-types.mm | ||
| msabi-stret.mm | ||
| nested-ehlocation.mm | ||
| nrvo.mm | ||
| objc-container-subscripting-1.mm | ||
| objc-container-subscripting.mm | ||
| objc-struct-cxx-abi.mm | ||
| objc-weak.mm | ||
| objfw-exceptions.mm | ||
| os_log.mm | ||
| personality-abuse.mm | ||
| personality.mm | ||
| pr14474-gline-tables-only.mm | ||
| property-derived-to-base-conv.mm | ||
| property-dot-copy-elision.mm | ||
| property-dot-copy.mm | ||
| property-dot-reference.mm | ||
| property-lvalue-capture.mm | ||
| property-lvalue-lambda.mm | ||
| property-object-conditional-exp.mm | ||
| property-object-reference-1.mm | ||
| property-object-reference-2.mm | ||
| property-object-reference.mm | ||
| property-objects.mm | ||
| property-reference.mm | ||
| refence-assign-write-barrier.mm | ||
| references.mm | ||
| return.mm | ||
| rtti.mm | ||
| selector-expr-lvalue.mm | ||
| subst-sel.mm | ||
| unknown-anytype.mm | ||
| write-barrier-global-assign.mm | ||