llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Rajveer Singh Bharadwaj (Rajveer100) <details> <summary>Changes</summary> Resolves #<!-- -->93066 --- Full diff: https://github.com/llvm/llvm-project/pull/94159.diff 3 Files Affected: - (modified) clang/include/clang/Basic/DiagnosticSemaKinds.td (+3) - (modified) clang/lib/Sema/SemaExpr.cpp (+13-2) - (added) clang/test/Sema/debug-93066.cpp (+14) ``````````diff diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index 270b0a1e01307..0f5445296e45f 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -8777,6 +8777,9 @@ def err_typecheck_incomplete_type_not_modifiable_lvalue : Error< def err_typecheck_lvalue_casts_not_supported : Error< "assignment to cast is illegal, lvalue casts are not supported">; +def note_typecheck_expression_not_modifiable_lvalue : Note< + "dereference the pointer to modify">; + def err_typecheck_duplicate_vector_components_not_mlvalue : Error< "vector is not assignable (contains duplicate components)">; def err_block_decl_ref_not_modifiable_lvalue : Error< diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index ff9c5ead36dcf..39e7962fcb2a6 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -13587,10 +13587,21 @@ static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { SourceRange Assign; if (Loc != OrigLoc) Assign = SourceRange(OrigLoc, OrigLoc); - if (NeedType) + if (NeedType) { S.Diag(Loc, DiagID) << E->getType() << E->getSourceRange() << Assign; - else + } else { + ExprResult Deref; + unsigned FixitDiagID = 0; + { + Sema::TentativeAnalysisScope Trap(S); + Deref = S.ActOnUnaryOp(S.getCurScope(), Loc, tok::star, E); + } S.Diag(Loc, DiagID) << E->getSourceRange() << Assign; + if (Deref.isUsable() && Deref.get()->isModifiableLvalue(S.Context, &Loc) == Expr::MLV_Valid) { + FixitDiagID = diag::note_typecheck_expression_not_modifiable_lvalue; + S.Diag(Loc, FixitDiagID) << E->getSourceRange() << Assign; + } + } return true; } diff --git a/clang/test/Sema/debug-93066.cpp b/clang/test/Sema/debug-93066.cpp new file mode 100644 index 0000000000000..7abedcd0d4d80 --- /dev/null +++ b/clang/test/Sema/debug-93066.cpp @@ -0,0 +1,14 @@ +// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify %s + +struct S { + void f() { + ++this; + // expected-error@-1 {{expression is not assignable}} + // expected-note@-2 {{dereference the pointer to modify}} + } + + void g() const { + ++this; + // expected-error@-1 {{expression is not assignable}} + } +}; `````````` </details> https://github.com/llvm/llvm-project/pull/94159 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
