llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Oleksandr T. (a-tarasyuk) <details> <summary>Changes</summary> Fixes #<!-- -->101863 --- Full diff: https://github.com/llvm/llvm-project/pull/110761.diff 4 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+2) - (modified) clang/lib/Sema/TreeTransform.h (+8-1) - (modified) clang/test/SemaCXX/warn-assignment-condition.cpp (+24-15) - (modified) clang/test/SemaTemplate/instantiate-requires-expr.cpp (+1-1) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index b7d287fdf4cc61..850a857e11abff 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -378,6 +378,8 @@ Improvements to Clang's diagnostics - Clang now emits a diagnostic note at the class declaration when the method definition does not match any declaration (#GH110638). +- Clang now omits warnings for extra parentheses in fold expressions with single expansion. (#GH101863) + Improvements to Clang's time-trace ---------------------------------- diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h index 04308b2b57d8a0..6a78ecc1229b3a 100644 --- a/clang/lib/Sema/TreeTransform.h +++ b/clang/lib/Sema/TreeTransform.h @@ -15566,6 +15566,14 @@ TreeTransform<Derived>::TransformCXXFoldExpr(CXXFoldExpr *E) { return true; } + // When there's only one expansion, the parentheses can be safely eliminated + // to avoid any extra redundancy that may result in incorrect checks + // For example, transforming (((args == 0) || ...)) into (args == 0) + // allows the omission of parentheses while ensuring precise representation + // and avoiding warnings regarding redundant parentheses. + if (*NumExpansions == 1) + Pattern = Pattern->IgnoreParens(); + for (unsigned I = 0; I != *NumExpansions; ++I) { Sema::ArgumentPackSubstitutionIndexRAII SubstIndex( getSema(), LeftFold ? I : *NumExpansions - I - 1); @@ -15623,7 +15631,6 @@ TreeTransform<Derived>::TransformCXXFoldExpr(CXXFoldExpr *E) { if (Result.isUnset()) return getDerived().RebuildEmptyCXXFoldExpr(E->getEllipsisLoc(), E->getOperator()); - return Result; } diff --git a/clang/test/SemaCXX/warn-assignment-condition.cpp b/clang/test/SemaCXX/warn-assignment-condition.cpp index 09084e36bb4916..ea169e8f9fa49c 100644 --- a/clang/test/SemaCXX/warn-assignment-condition.cpp +++ b/clang/test/SemaCXX/warn-assignment-condition.cpp @@ -1,4 +1,4 @@ -// RUN: %clang_cc1 -fsyntax-only -Wparentheses -verify %s +// RUN: %clang_cc1 -fsyntax-only -Wparentheses -std=c++2a -verify %s struct A { int foo(); @@ -122,25 +122,34 @@ void test() { #undef EQ } -void (*fn)(); +namespace GH101863 { +void t1(auto... args) { + if (((args == 0) or ...)) { } +} + +template <typename... Args> +void t2(Args... args) { + if (((args == 0) or ...)) { } +} + +void t3(auto... args) { + if ((... && (args == 0))) { } +} -void test2() { - if ((fn == test2)) {} // expected-warning {{equality comparison with extraneous parentheses}} \ - // expected-note {{use '=' to turn this equality comparison into an assignment}} \ - // expected-note {{remove extraneous parentheses around the comparison to silence this warning}} - if ((test2 == fn)) {} +void t4(auto... a, auto... b) { + if (((a == 0) or ...) && ((b == 0) or ...)) { } } -namespace rdar9027658 { -template <typename T> -void f(T t) { - if ((t.g == 3)) { } // expected-warning {{equality comparison with extraneous parentheses}} \ - // expected-note {{use '=' to turn this equality comparison into an assignment}} \ - // expected-note {{remove extraneous parentheses around the comparison to silence this warning}} +void t5(auto... args) { + if ((((args == 0) or ...))) { } } -struct S { int g; }; void test() { - f(S()); // expected-note {{in instantiation}} + t1(0, 1); + t2<>(); + t3(1, 2, 3); + t3(0, 1); + t4(0, 1); + t5(0, 1); } } diff --git a/clang/test/SemaTemplate/instantiate-requires-expr.cpp b/clang/test/SemaTemplate/instantiate-requires-expr.cpp index 20a19d731ae169..ce2c060a176045 100644 --- a/clang/test/SemaTemplate/instantiate-requires-expr.cpp +++ b/clang/test/SemaTemplate/instantiate-requires-expr.cpp @@ -36,7 +36,7 @@ using r1i2 = r1<char>; // expected-error {{constraints not satisfied for class t template<typename... Ts> requires false_v<requires (Ts... ts) {requires ((sizeof(ts) == 2) && ...);}> // expected-note@-1 {{because 'false_v<requires (short ts, unsigned short ts) { requires (sizeof (ts) == 2) && (sizeof (ts) == 2); }>'}} -// expected-note@-2 {{because 'false_v<requires (short ts) { requires (sizeof (ts) == 2); }>' evaluated to false}} +// expected-note@-2 {{because 'false_v<requires (short ts) { requires sizeof (ts) == 2; }>' evaluated to false}} struct r2 {}; using r2i1 = r2<short, unsigned short>; // expected-error {{constraints not satisfied for class template 'r2' [with Ts = <short, unsigned short>]}} `````````` </details> https://github.com/llvm/llvm-project/pull/110761 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
