Author: Mythreya Kuricheti Date: 2025-12-21T05:33:00Z New Revision: 4fec70204fe99ce9dcb9eb34fbfb1b57f45d910f
URL: https://github.com/llvm/llvm-project/commit/4fec70204fe99ce9dcb9eb34fbfb1b57f45d910f DIFF: https://github.com/llvm/llvm-project/commit/4fec70204fe99ce9dcb9eb34fbfb1b57f45d910f.diff LOG: [clang] Add FixItHint for designated init order (#173136) Generate fix-it for C++20 designated initializers when the initializers do not match the declaration order in the structure. Added: clang/test/SemaCXX/cxx20-designated-initializer-fixits.cpp Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaInit.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 994ac444d4aa1..ba14a50c1f177 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -493,6 +493,9 @@ Improvements to Clang's diagnostics carries messages like 'In file included from ...' or 'In module ...'. Now the include/import locations are written into `sarif.run.result.relatedLocations`. +- Clang now generates a fix-it for C++20 designated initializers when the + initializers do not match the declaration order in the structure. + Improvements to Clang's time-trace ---------------------------------- diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp index cc6ddf568d346..ff278bc7471bd 100644 --- a/clang/lib/Sema/SemaInit.cpp +++ b/clang/lib/Sema/SemaInit.cpp @@ -31,8 +31,10 @@ #include "clang/Sema/SemaHLSL.h" #include "clang/Sema/SemaObjC.h" #include "llvm/ADT/APInt.h" +#include "llvm/ADT/DenseMap.h" #include "llvm/ADT/FoldingSet.h" #include "llvm/ADT/PointerIntPair.h" +#include "llvm/ADT/SmallString.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/StringExtras.h" #include "llvm/Support/ErrorHandling.h" @@ -3092,6 +3094,65 @@ InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, PrevField = *FI; } + const auto GenerateDesignatedInitReorderingFixit = + [&](SemaBase::SemaDiagnosticBuilder &Diag) { + struct ReorderInfo { + int Pos{}; + const Expr *InitExpr{}; + }; + + llvm::SmallDenseMap<IdentifierInfo *, int> MemberNameInx{}; + llvm::SmallVector<ReorderInfo, 16> ReorderedInitExprs{}; + + const auto *CxxRecord = + IList->getSemanticForm()->getType()->getAsCXXRecordDecl(); + + for (const FieldDecl *Field : CxxRecord->fields()) + MemberNameInx[Field->getIdentifier()] = Field->getFieldIndex(); + + for (const Expr *Init : IList->inits()) { + if (const auto *DI = + dyn_cast_if_present<DesignatedInitExpr>(Init)) { + // We expect only one Designator + if (DI->size() != 1) + return; + + const IdentifierInfo *const FieldName = + DI->getDesignator(0)->getFieldName(); + // In case we have an unknown initializer in the source, not in + // the record + if (MemberNameInx.contains(FieldName)) + ReorderedInitExprs.emplace_back( + ReorderInfo{MemberNameInx.at(FieldName), Init}); + } + } + + llvm::sort(ReorderedInitExprs, + [](const ReorderInfo &A, const ReorderInfo &B) { + return A.Pos < B.Pos; + }); + + llvm::SmallString<128> FixedInitList{}; + SourceManager &SM = SemaRef.getSourceManager(); + const LangOptions &LangOpts = SemaRef.getLangOpts(); + + // In a derived Record, first n base-classes are initialized first. + // They do not use designated init, so skip them + const ArrayRef<clang::Expr *> IListInits = + IList->inits().drop_front(CxxRecord->getNumBases()); + // loop over each existing expressions and apply replacement + for (const auto &[OrigExpr, Repl] : + llvm::zip(IListInits, ReorderedInitExprs)) { + CharSourceRange CharRange = CharSourceRange::getTokenRange( + Repl.InitExpr->getSourceRange()); + const StringRef InitText = + Lexer::getSourceText(CharRange, SM, LangOpts); + + Diag << FixItHint::CreateReplacement(OrigExpr->getSourceRange(), + InitText.str()); + } + }; + if (PrevField && PrevField->getFieldIndex() > KnownField->getFieldIndex()) { SemaRef.Diag(DIE->getInit()->getBeginLoc(), @@ -3101,9 +3162,10 @@ InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, unsigned OldIndex = StructuredIndex - 1; if (StructuredList && OldIndex <= StructuredList->getNumInits()) { if (Expr *PrevInit = StructuredList->getInit(OldIndex)) { - SemaRef.Diag(PrevInit->getBeginLoc(), - diag::note_previous_field_init) - << PrevField << PrevInit->getSourceRange(); + auto Diag = SemaRef.Diag(PrevInit->getBeginLoc(), + diag::note_previous_field_init) + << PrevField << PrevInit->getSourceRange(); + GenerateDesignatedInitReorderingFixit(Diag); } } } diff --git a/clang/test/SemaCXX/cxx20-designated-initializer-fixits.cpp b/clang/test/SemaCXX/cxx20-designated-initializer-fixits.cpp new file mode 100644 index 0000000000000..7dfdd62df292f --- /dev/null +++ b/clang/test/SemaCXX/cxx20-designated-initializer-fixits.cpp @@ -0,0 +1,105 @@ +// RUN: %clang_cc1 -std=c++20 %s -Wreorder-init-list -fdiagnostics-parseable-fixits 2>&1 | FileCheck %s + +// These tests are from clang/test/SemaCXX/cxx2a-initializer-aggregates.cpp +struct C { int :0, x, :0, y, :0; }; +C c = { + .x = 1, + .x = 1, + .y = 1, + .y = 1, + .x = 1, + .x = 1, +}; +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:3-[[@LINE-7]]:9}:".x = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:3-[[@LINE-7]]:9}:".x = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:3-[[@LINE-7]]:9}:".x = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:3-[[@LINE-7]]:9}:".x = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:3-[[@LINE-7]]:9}:".y = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:3-[[@LINE-7]]:9}:".y = 1" + +namespace GH63605 { +struct A { + unsigned x; + unsigned y; + unsigned z; +}; + +struct B { + unsigned a; + unsigned b; +}; + +struct : public A, public B { + unsigned : 2; + unsigned a : 6; + unsigned : 1; + unsigned b : 6; + unsigned : 2; + unsigned c : 6; + unsigned d : 1; + unsigned e : 2; +} data = { + {.z=0, + + + .y=1, + + .x=2}, + {.b=3, + .a=4}, + .e = 1, + + .d = 1, + + .c = 1, + .b = 1, + .a = 1, +}; +} +// CHECK: fix-it:"{{.*}}":{[[@LINE-17]]:4-[[@LINE-17]]:8}:".x=2" +// CHECK: fix-it:"{{.*}}":{[[@LINE-15]]:4-[[@LINE-15]]:8}:".y=1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-14]]:4-[[@LINE-14]]:8}:".z=0" +// CHECK: fix-it:"{{.*}}":{[[@LINE-14]]:4-[[@LINE-14]]:8}:".a=4" +// CHECK: fix-it:"{{.*}}":{[[@LINE-14]]:4-[[@LINE-14]]:8}:".b=3" +// CHECK: fix-it:"{{.*}}":{[[@LINE-14]]:5-[[@LINE-14]]:11}:".a = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-13]]:5-[[@LINE-13]]:11}:".b = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-12]]:5-[[@LINE-12]]:11}:".c = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-12]]:5-[[@LINE-12]]:11}:".d = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-12]]:5-[[@LINE-12]]:11}:".e = 1" +// END tests from clang/test/SemaCXX/cxx2a-initializer-aggregates.cpp + +namespace reorder_derived { +struct col { + int r; + int g; + int b; +}; + +struct point { + float x; + float y; + float z; +}; + +struct derived : public col, public point { + int z2; + int z1; +}; + +void test() { + derived a { + {.b = 1, .g = 2, .r = 3}, + { .z = 1, .y=2, .x = 3 }, + .z1 = 1, + .z2 = 2, + }; +} +// CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:6-[[@LINE-6]]:12}:".r = 3" +// CHECK: fix-it:"{{.*}}":{[[@LINE-7]]:14-[[@LINE-7]]:20}:".g = 2" +// CHECK: fix-it:"{{.*}}":{[[@LINE-8]]:22-[[@LINE-8]]:28}:".b = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-8]]:15-[[@LINE-8]]:19}:".y=2" +// CHECK: fix-it:"{{.*}}":{[[@LINE-9]]:21-[[@LINE-9]]:28}:".z = 1" +// CHECK: fix-it:"{{.*}}":{[[@LINE-10]]:7-[[@LINE-10]]:13}:".x = 3" +// CHECK: fix-it:"{{.*}}":{[[@LINE-10]]:5-[[@LINE-10]]:12}:".z2 = 2" +// CHECK: fix-it:"{{.*}}":{[[@LINE-10]]:5-[[@LINE-10]]:12}:".z1 = 1" +} // namespace reorder_derived _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
