https://github.com/bjosv created https://github.com/llvm/llvm-project/pull/89990
C23 introduces the `nullptr` constant similar to C++11 which means that the checker `modernize-use-nullptr` can be used on C23 code as well. This PR enables the checker to be run on C23 and adds testcases. See N3042: https://open-std.org/JTC1/SC22/WG14/www/docs/n3042.htm From 6e4e72cc371a5607616546c7b2ed7bf8386acd4c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Svensson?= <bjorn.a.svens...@est.tech> Date: Wed, 24 Apr 2024 22:39:48 +0200 Subject: [PATCH] [clang-tidy] Enable C23 support in modernize-use-nullptr C23 introduces the nullptr constant similar to C++11 which means that the checker modernize-use-nullptr can be used on C23 code as well. See N3042: https://open-std.org/JTC1/SC22/WG14/www/docs/n3042.htm --- .../clang-tidy/modernize/UseNullptrCheck.h | 2 +- clang-tools-extra/docs/ReleaseNotes.rst | 4 + .../checks/modernize/use-nullptr.rst | 2 +- .../checkers/modernize/use-nullptr-c23.c | 139 ++++++++++++++++++ .../checkers/modernize/use-nullptr.c | 2 +- 5 files changed, 146 insertions(+), 3 deletions(-) create mode 100644 clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr-c23.c diff --git a/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.h b/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.h index 6c32a4edb4ff96..f1591bae446579 100644 --- a/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.h +++ b/clang-tools-extra/clang-tidy/modernize/UseNullptrCheck.h @@ -19,7 +19,7 @@ class UseNullptrCheck : public ClangTidyCheck { bool isLanguageVersionSupported(const LangOptions &LangOpts) const override { // FIXME this should be CPlusPlus11 but that causes test cases to // erroneously fail. - return LangOpts.CPlusPlus; + return LangOpts.CPlusPlus || LangOpts.C23; } void storeOptions(ClangTidyOptions::OptionMap &Opts) override; void registerMatchers(ast_matchers::MatchFinder *Finder) override; diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 7095c564444fe6..953453219221e8 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -253,6 +253,10 @@ Changes in existing checks <clang-tidy/checks/modernize/use-override>` check to also remove any trailing whitespace when deleting the ``virtual`` keyword. +- Improved :doc:`modernize-use-nullptr + <clang-tidy/checks/modernize/use-nullptr>` check to include support for + ``C23``, which also has introduced the ``nullptr`` keyword. + - Improved :doc:`modernize-use-using <clang-tidy/checks/modernize/use-using>` check by adding support for detection of typedefs declared on function level. diff --git a/clang-tools-extra/docs/clang-tidy/checks/modernize/use-nullptr.rst b/clang-tools-extra/docs/clang-tidy/checks/modernize/use-nullptr.rst index 5e1ba858adf3a9..25e17fee0a3d61 100644 --- a/clang-tools-extra/docs/clang-tidy/checks/modernize/use-nullptr.rst +++ b/clang-tools-extra/docs/clang-tidy/checks/modernize/use-nullptr.rst @@ -4,7 +4,7 @@ modernize-use-nullptr ===================== The check converts the usage of null pointer constants (e.g. ``NULL``, ``0``) -to use the new C++11 ``nullptr`` keyword. +to use the new C++11 and C23 ``nullptr`` keyword. Example ------- diff --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr-c23.c b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr-c23.c new file mode 100644 index 00000000000000..6fb879b91e41c1 --- /dev/null +++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr-c23.c @@ -0,0 +1,139 @@ +// RUN: %check_clang_tidy %s modernize-use-nullptr %t -- -- -std=c23 + +#define NULL 0 + +void test_assignment() { + int *p1 = 0; + // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: use nullptr [modernize-use-nullptr] + // CHECK-FIXES: int *p1 = nullptr; + p1 = 0; + // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: use nullptr + // CHECK-FIXES: p1 = nullptr; + + int *p2 = NULL; + // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: use nullptr + // CHECK-FIXES: int *p2 = nullptr; + + p2 = p1; + // CHECK-FIXES: p2 = p1; + + const int null = 0; + int *p3 = &null; + + p3 = NULL; + // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: use nullptr + // CHECK-FIXES: p3 = nullptr; + + int *p4 = p3; + + int i1 = 0; + + int i2 = NULL; + + int i3 = null; + + int *p5, *p6, *p7; + p5 = p6 = p7 = NULL; + // CHECK-MESSAGES: :[[@LINE-1]]:18: warning: use nullptr + // CHECK-FIXES: p5 = p6 = p7 = nullptr; +} + +void test_function(int *p) {} + +void test_function_no_ptr_param(int i) {} + +void test_function_call() { + test_function(0); + // CHECK-MESSAGES: :[[@LINE-1]]:17: warning: use nullptr + // CHECK-FIXES: test_function(nullptr); + + test_function(NULL); + // CHECK-MESSAGES: :[[@LINE-1]]:17: warning: use nullptr + // CHECK-FIXES: test_function(nullptr); + + test_function_no_ptr_param(0); +} + +char *test_function_return1() { + return 0; + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: use nullptr + // CHECK-FIXES: return nullptr; +} + +void *test_function_return2() { + return NULL; + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: use nullptr + // CHECK-FIXES: return nullptr; +} + +int test_function_return4() { + return 0; +} + +int test_function_return5() { + return NULL; +} + +int *test_function_return_cast1() { + return(int)0; + // CHECK-MESSAGES: :[[@LINE-1]]:9: warning: use nullptr + // CHECK-FIXES: return nullptr; +} + +int *test_function_return_cast2() { +#define RET return + RET(int)0; + // CHECK-MESSAGES: :[[@LINE-1]]:6: warning: use nullptr + // CHECK-FIXES: RET nullptr; +#undef RET +} + +// Test parentheses expressions resulting in a nullptr. +int *test_parentheses_expression1() { + return(0); + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: use nullptr + // CHECK-FIXES: return(nullptr); +} + +int *test_parentheses_expression2() { + return((int)(0.0f)); + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: use nullptr + // CHECK-FIXES: return(nullptr); +} + +int *test_nested_parentheses_expression() { + return((((0)))); + // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: use nullptr + // CHECK-FIXES: return((((nullptr)))); +} + +void test_const_pointers() { + const int *const_p1 = 0; + // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: use nullptr + // CHECK-FIXES: const int *const_p1 = nullptr; + const int *const_p2 = NULL; + // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: use nullptr + // CHECK-FIXES: const int *const_p2 = nullptr; + const int *const_p3 = (int)0; + // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: use nullptr + // CHECK-FIXES: const int *const_p3 = nullptr; + const int *const_p4 = (int)0.0f; + // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: use nullptr + // CHECK-FIXES: const int *const_p4 = nullptr; +} + +void test_nested_implicit_cast_expr() { + int func0(void*, void*); + int func1(int, void*, void*); + + (double)func1(0, 0, 0); + // CHECK-MESSAGES: :[[@LINE-1]]:20: warning: use nullptr + // CHECK-MESSAGES: :[[@LINE-2]]:23: warning: use nullptr + // CHECK-FIXES: (double)func1(0, nullptr, nullptr); + (double)func1(func0(0, 0), 0, 0); + // CHECK-MESSAGES: :[[@LINE-1]]:23: warning: use nullptr + // CHECK-MESSAGES: :[[@LINE-2]]:26: warning: use nullptr + // CHECK-MESSAGES: :[[@LINE-3]]:30: warning: use nullptr + // CHECK-MESSAGES: :[[@LINE-4]]:33: warning: use nullptr + // CHECK-FIXES: (double)func1(func0(nullptr, nullptr), nullptr, nullptr); +} diff --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.c b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.c index c2ccbbd8117152..1218b837199c0c 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.c +++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-nullptr.c @@ -1,4 +1,4 @@ -// RUN: clang-tidy %s -checks=-*,modernize-use-nullptr -- | count 0 +// RUN: clang-tidy %s -checks=-*,modernize-use-nullptr -- -std=c17 | count 0 // Note: this test expects no diagnostics, but FileCheck cannot handle that, // hence the use of | count 0. _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits