diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index de5f339cc7f0b..5e0352a7eaf6c 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -150,6 +150,10 @@ Non-comprehensive list of changes in this release New Compiler Flags ------------------ +- ``-Wmissing-designated-field-initializers``, grouped under ``-Wmissing-field-initializers``. + This diagnostic can be disabled to make ``-Wmissing-field-initializers`` behave + like it did before Clang 18.x. Fixes (`#56628 `_) + Deprecated Compiler Flags ------------------------- diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index e8b4139d7893c..0791a0002319d 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -517,7 +517,15 @@ def MethodSignatures : DiagGroup<"method-signatures">; def MismatchedParameterTypes : DiagGroup<"mismatched-parameter-types">; def MismatchedReturnTypes : DiagGroup<"mismatched-return-types">; def MismatchedTags : DiagGroup<"mismatched-tags">; -def MissingFieldInitializers : DiagGroup<"missing-field-initializers">; +def MissingDesignatedFieldInitializers : DiagGroup<"missing-designated-field-initializers">{ + code Documentation = [{ +Warn about designated initializers with some fields missing (only in C++). + }]; +} +// Default -Wmissing-field-initializers matches gcc behavior, +// but missing-designated-field-initializers can be turned off to match old clang behavior. +def MissingFieldInitializers : DiagGroup<"missing-field-initializers", + [MissingDesignatedFieldInitializers]>; def ModuleLock : DiagGroup<"module-lock">; def ModuleBuild : DiagGroup<"module-build">; def ModuleImport : DiagGroup<"module-import">; diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index b50a4895e171b..708b3c7f1ede0 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -6170,6 +6170,10 @@ def ext_initializer_string_for_char_array_too_long : ExtWarn< def warn_missing_field_initializers : Warning< "missing field %0 initializer">, InGroup, DefaultIgnore; +// The same warning, but another group is needed to disable it separately. +def warn_missing_designated_field_initializers : Warning< + warn_missing_field_initializers.Summary>, + InGroup, DefaultIgnore; def warn_braces_around_init : Warning< "braces around %select{scalar |}0initializer">, InGroup>; diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp index 93b125382b164..060fe35ad9680 100644 --- a/clang/lib/Sema/SemaInit.cpp +++ b/clang/lib/Sema/SemaInit.cpp @@ -2227,8 +2227,6 @@ void InitListChecker::CheckStructUnionTypes( size_t NumRecordDecls = llvm::count_if(RD->decls(), [&](const Decl *D) { return isa(D) || isa(D); }); - bool CheckForMissingFields = - !IList->isIdiomaticZeroInitializer(SemaRef.getLangOpts()); bool HasDesignatedInit = false; llvm::SmallPtrSet InitializedFields; @@ -2269,11 +2267,6 @@ void InitListChecker::CheckStructUnionTypes( } InitializedSomething = true; - - // Disable check for missing fields when designators are used. - // This matches gcc behaviour. - if (!SemaRef.getLangOpts().CPlusPlus) - CheckForMissingFields = false; continue; } @@ -2285,7 +2278,7 @@ void InitListChecker::CheckStructUnionTypes( // These are okay for randomized structures. [C99 6.7.8p19] // // Also, if there is only one element in the structure, we allow something - // like this, because it's really not randomized in the tranditional sense. + // like this, because it's really not randomized in the traditional sense. // // struct foo h = {bar}; auto IsZeroInitializer = [&](const Expr *I) { @@ -2363,8 +2356,13 @@ void InitListChecker::CheckStructUnionTypes( } // Emit warnings for missing struct field initializers. - if (!VerifyOnly && InitializedSomething && CheckForMissingFields && - !RD->isUnion()) { + // This check is disabled for designated initializers in C. + // This matches gcc behaviour. + bool IsCDesignatedInitializer = + HasDesignatedInit && !SemaRef.getLangOpts().CPlusPlus; + if (!VerifyOnly && InitializedSomething && !RD->isUnion() && + !IList->isIdiomaticZeroInitializer(SemaRef.getLangOpts()) && + !IsCDesignatedInitializer) { // It is possible we have one or more unnamed bitfields remaining. // Find first (if any) named field and emit warning. for (RecordDecl::field_iterator it = HasDesignatedInit ? RD->field_begin() @@ -2376,9 +2374,10 @@ void InitListChecker::CheckStructUnionTypes( if (!it->isUnnamedBitfield() && !it->hasInClassInitializer() && !it->getType()->isIncompleteArrayType()) { - SemaRef.Diag(IList->getSourceRange().getEnd(), - diag::warn_missing_field_initializers) - << *it; + auto Diag = HasDesignatedInit + ? diag::warn_missing_designated_field_initializers + : diag::warn_missing_field_initializers; + SemaRef.Diag(IList->getSourceRange().getEnd(), Diag) << *it; break; } } diff --git a/clang/test/SemaCXX/cxx2a-initializer-aggregates.cpp b/clang/test/SemaCXX/cxx2a-initializer-aggregates.cpp index 510ace58c35a6..1e9c5fa082d07 100644 --- a/clang/test/SemaCXX/cxx2a-initializer-aggregates.cpp +++ b/clang/test/SemaCXX/cxx2a-initializer-aggregates.cpp @@ -4,7 +4,8 @@ // RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,reorder -Wno-c99-designator -Werror=reorder-init-list -Wno-initializer-overrides // RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,override -Wno-c99-designator -Wno-reorder-init-list -Werror=initializer-overrides // RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides -// RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,wmissing -Wmissing-field-initializers -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides +// RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,wmissing,wmissing-designated -Wmissing-field-initializers -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides +// RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,wmissing -Wmissing-field-initializers -Wno-missing-designated-field-initializers -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides namespace class_with_ctor { @@ -50,11 +51,11 @@ A a3 = { A a4 = { .x = 1, // override-note {{previous}} .x = 1 // override-error {{overrides prior initialization}} -}; // wmissing-warning {{missing field 'y' initializer}} +}; // wmissing-designated-warning {{missing field 'y' initializer}} A a5 = { .y = 1, // override-note {{previous}} .y = 1 // override-error {{overrides prior initialization}} -}; // wmissing-warning {{missing field 'x' initializer}} +}; // wmissing-designated-warning {{missing field 'x' initializer}} B b2 = {.a = 1}; // pedantic-error {{brace elision for designated initializer is a C99 extension}} // wmissing-warning@-1 {{missing field 'y' initializer}} B b3 = {.a = 1, 2}; // pedantic-error {{mixture of designated and non-designated}} pedantic-note {{first non-designated}} pedantic-error {{brace elision}} @@ -74,8 +75,8 @@ C c = { struct Foo { int a, b; }; struct Foo foo0 = { 1 }; // wmissing-warning {{missing field 'b' initializer}} -struct Foo foo1 = { .a = 1 }; // wmissing-warning {{missing field 'b' initializer}} -struct Foo foo2 = { .b = 1 }; // wmissing-warning {{missing field 'a' initializer}} +struct Foo foo1 = { .a = 1 }; // wmissing-designated-warning {{missing field 'b' initializer}} +struct Foo foo2 = { .b = 1 }; // wmissing-designated-warning {{missing field 'a' initializer}} }