https://github.com/tkoeppe updated https://github.com/llvm/llvm-project/pull/109169
From d8a46761ef175194c7e7272313807d2ef25aa497 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20K=C3=B6ppe?= <tkoe...@google.com> Date: Wed, 18 Sep 2024 17:04:44 +0000 Subject: [PATCH] [clang-tidy] Make modernize-use-nullptr matcher also match "NULL", but not "0", when it appears on a substituted type of a template specialization. Previously, any matches on a substituted type were excluded, but this meant that a situation like the following is not diagnosed: ```c++ template <typename T> struct X { T val; X() { val = NULL; } // should diagnose }; ``` When the user says `NULL`, we expect that the destination type is always meant to be a pointer type, so this should be converted to `nullptr`. By contrast, we do not propose changing a literal `0` in that case, which appears as initializers of both pointer and integer specializations in reasonable real code. (If `NULL` is used erroneously in such a situation, it should be changed to `0` or `{}`.) --- .../clang-tidy/modernize/UseNullptrCheck.cpp | 4 +++- .../checkers/modernize/use-nullptr.cpp | 22 +++++++++++++++++++ 2 files changed, 25 insertions(+), 1 deletion(-) diff --git a/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.cpp b/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.cpp index 6a003a347badac..b2921690863b84 100644 --- a/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.cpp +++ b/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.cpp @@ -38,7 +38,9 @@ AST_MATCHER(Type, sugaredNullptrType) { StatementMatcher makeCastSequenceMatcher(llvm::ArrayRef<StringRef> NameList) { auto ImplicitCastToNull = implicitCastExpr( anyOf(hasCastKind(CK_NullToPointer), hasCastKind(CK_NullToMemberPointer)), - unless(hasImplicitDestinationType(qualType(substTemplateTypeParmType()))), + anyOf(hasSourceExpression(gnuNullExpr()), + unless(hasImplicitDestinationType( + qualType(substTemplateTypeParmType())))), unless(hasSourceExpression(hasType(sugaredNullptrType()))), unless(hasImplicitDestinationType( qualType(matchers::matchesAnyListedTypeName(NameList))))); diff --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.cpp b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.cpp index 7bc0925136aa86..c32524eee88bc8 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.cpp @@ -84,6 +84,28 @@ void test_macro_expansion4() { #undef MY_NULL } +template <typename T> struct pear { + // If you say __null (or NULL), we assume that T will always be a pointer + // type, so we suggest replacing it with nullptr. + void f() { x = __null; } + // CHECK-MESSAGES: :[[@LINE-1]]:18: warning: use nullptr [modernize-use-nullptr] + // CHECK-FIXES: x = nullptr; + + // But if you say 0, we allow the possibility that T can be used with integral + // and pointer types, and "0" is an acceptable initializer (even if "{}" might + // be even better). + void g() { y = 0; } + + T x; + T y; +}; +void test_templated() { + pear<int*> p; + p.f(); + p.g(); + dummy(p.x); +} + #define IS_EQ(x, y) if (x != y) return; void test_macro_args() { int i = 0; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits