llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Oleksandr T. (a-tarasyuk) <details> <summary>Changes</summary> Fixes #<!-- -->153745 --- This PR addresses a limitation in `-Wstring-concatenation`, where only the first missing comma in an initializer list was diagnosed. --- Full diff: https://github.com/llvm/llvm-project/pull/154018.diff 3 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+2) - (modified) clang/lib/Sema/SemaDecl.cpp (+26-19) - (modified) clang/test/Sema/string-concat.c (+14) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index b35f4ea42818a..48575b6e821f0 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -162,6 +162,8 @@ Improvements to Clang's diagnostics an override of a virtual method. - Fixed fix-it hint for fold expressions. Clang now correctly places the suggested right parenthesis when diagnosing malformed fold expressions. (#GH151787) +- ``-Wstring-concatenation`` now diagnoses every missing comma in an initializer list, + rather than stopping after the first. (#GH153745) - Fixed an issue where emitted format-signedness diagnostics were not associated with an appropriate diagnostic id. Besides being incorrect from an API standpoint, this was user visible, e.g.: diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index 8ddbaf34a7f47..b63c157d81dc8 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -14708,7 +14708,16 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { isa<InitListExpr>(var->getInit())) { const auto *ILE = cast<InitListExpr>(var->getInit()); unsigned NumInits = ILE->getNumInits(); - if (NumInits > 2) + if (NumInits > 2) { + auto concatenatedPartsAt = [&](unsigned Index) -> unsigned { + const Expr *E = ILE->getInit(Index); + if (E) { + if (const auto *S = dyn_cast<StringLiteral>(E->IgnoreImpCasts())) + return S->getNumConcatenated(); + } + return 0; + }; + for (unsigned I = 0; I < NumInits; ++I) { const auto *Init = ILE->getInit(I); if (!Init) @@ -14721,24 +14730,23 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { // Diagnose missing comma in string array initialization. // Do not warn when all the elements in the initializer are concatenated // together. Do not warn for macros too. - if (NumConcat == 2 && !SL->getBeginLoc().isMacroID()) { - bool OnlyOneMissingComma = true; - for (unsigned J = I + 1; J < NumInits; ++J) { - const auto *Init = ILE->getInit(J); - if (!Init) - break; - const auto *SLJ = dyn_cast<StringLiteral>(Init->IgnoreImpCasts()); - if (!SLJ || SLJ->getNumConcatenated() > 1) { - OnlyOneMissingComma = false; - break; - } - } + if (NumConcat == 2) { + if (SL->getBeginLoc().isMacroID()) + continue; + + unsigned L = I > 0 ? concatenatedPartsAt(I - 1) : 0; + unsigned R = I + 1 < NumInits ? concatenatedPartsAt(I + 1) : 0; + + // Skip neighbors with multi-part concatenations. + if (L > 1 || R > 1) + continue; - if (OnlyOneMissingComma) { + // Diagnose when at least one neighbor is a single literal. + if (L || R) { SmallVector<FixItHint, 1> Hints; - for (unsigned i = 0; i < NumConcat - 1; ++i) - Hints.push_back(FixItHint::CreateInsertion( - PP.getLocForEndOfToken(SL->getStrTokenLoc(i)), ",")); + // Insert a comma between the two tokens of this element. + Hints.push_back(FixItHint::CreateInsertion( + PP.getLocForEndOfToken(SL->getStrTokenLoc(0)), ", ")); Diag(SL->getStrTokenLoc(1), diag::warn_concatenated_literal_array_init) @@ -14746,10 +14754,9 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { Diag(SL->getBeginLoc(), diag::note_concatenated_string_literal_silence); } - // In any case, stop now. - break; } } + } } diff --git a/clang/test/Sema/string-concat.c b/clang/test/Sema/string-concat.c index 63abf100c020f..ae6c0897878a7 100644 --- a/clang/test/Sema/string-concat.c +++ b/clang/test/Sema/string-concat.c @@ -168,3 +168,17 @@ const char *extra_parens_to_suppress_warning[] = { "promise"), "shared_future" }; + +const char *multiple_missing_commas[] = { + "1", + "2" // expected-note {{place parentheses around the string literal to silence warning}} + "3", // expected-warning {{suspicious concatenation of string literals in an array initialization; did you mean to separate the elements with a comma?}} + "4", + "5", + "6" // expected-note {{place parentheses around the string literal to silence warning}} + "7", // expected-warning {{suspicious concatenation of string literals in an array initialization; did you mean to separate the elements with a comma?}} + "8", + "9", + "10", + "11", +}; `````````` </details> https://github.com/llvm/llvm-project/pull/154018 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
