llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang <details> <summary>Changes</summary> The checker EnumCastOutOfRange verifies the (helpful, but not standard-mandated) design rule that integer to enum casts should not produce values that don't have a corresponding enumerator. As it was improved and cleaned up by recent changes, this commit renames it from `alpha.cplusplus.EnumCastOutOfRange` to `optin.core.EnumCastOutOfRange` to reflect that it's no longer alpha quality. As this checker handles a basic language feature (which is also present in plain C), I moved it to a "core" subpackage within "optin". In addition to the renaming, this commit cleans up the documentation in `checkers.rst` and adds the new example code to a test file to ensure that it's indeed producing the behavior claimend in the documentation. --- Full diff: https://github.com/llvm/llvm-project/pull/67157.diff 6 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+3) - (modified) clang/docs/analyzer/checkers.rst (+22-17) - (modified) clang/include/clang/StaticAnalyzer/Checkers/Checkers.td (+13-4) - (modified) clang/test/Analysis/enum-cast-out-of-range.c (+1-1) - (modified) clang/test/Analysis/enum-cast-out-of-range.cpp (+12-1) - (modified) clang/www/analyzer/alpha_checks.html (-19) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 477a40630f11097..522272a81c088f1 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -491,6 +491,9 @@ Static Analyzer Read the PR for the details. (`#66086 <https://github.com/llvm/llvm-project/pull/66086>`_) +- Move checker ``alpha.cplusplus.EnumCastOutOfRange`` out of the ``alpha`` + package to ``optin.core.EnumCastOutOfRange``. + .. _release-notes-sanitizers: Sanitizers diff --git a/clang/docs/analyzer/checkers.rst b/clang/docs/analyzer/checkers.rst index dbd6d7787823530..552f7676a328371 100644 --- a/clang/docs/analyzer/checkers.rst +++ b/clang/docs/analyzer/checkers.rst @@ -535,6 +535,28 @@ optin Checkers for portability, performance or coding style specific rules. +.. _optin-core-EnumCastOutOfRange: + +optin.core.EnumCastOutOfRange (C, C++) +"""""""""""""""""""""""""""""""""""""" +Check for integer to enumeration casts that would produce a value with no +corresponding enumerator. This is not necessarily undefined behavior, but can +lead to nasty surprises, so projects may decide to use a coding standard that +disallows these "unusual" conversions. + +Note that no warnings are produced when the enum type (e.g. `std::byte`) has no +enumerators at all. + +.. code-block:: cpp + + enum WidgetKind { A=1, B, C, X=99 }; + + void foo() { + WidgetKind c = static_cast<WidgetKind>(3); // OK + WidgetKind x = static_cast<WidgetKind>(99); // OK + WidgetKind d = static_cast<WidgetKind>(4); // warn + } + .. _optin-cplusplus-UninitializedObject: optin.cplusplus.UninitializedObject (C++) @@ -1853,23 +1875,6 @@ Reports destructions of polymorphic objects with a non-virtual destructor in the // destructor } -.. _alpha-cplusplus-EnumCastOutOfRange: - -alpha.cplusplus.EnumCastOutOfRange (C++) -"""""""""""""""""""""""""""""""""""""""" -Check for integer to enumeration casts that could result in undefined values. - -.. code-block:: cpp - - enum TestEnum { - A = 0 - }; - - void foo() { - TestEnum t = static_cast(-1); - // warn: the value provided to the cast expression is not in - // the valid range of values for the enum - .. _alpha-cplusplus-InvalidatedIterator: alpha.cplusplus.InvalidatedIterator (C++) diff --git a/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td b/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td index 65c1595eb6245dd..1c859c39cf44d91 100644 --- a/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td +++ b/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td @@ -36,6 +36,7 @@ def CoreAlpha : Package<"core">, ParentPackage<Alpha>; // Note: OptIn is *not* intended for checkers that are too noisy to be on by // default. Such checkers belong in the alpha package. def OptIn : Package<"optin">; +def CoreOptIn : Package<"core">, ParentPackage<OptIn>; // In the Portability package reside checkers for finding code that relies on // implementation-defined behavior. Such checks are wanted for cross-platform @@ -433,6 +434,18 @@ def UndefinedNewArraySizeChecker : Checker<"NewArraySize">, } // end "core.uninitialized" +//===----------------------------------------------------------------------===// +// Optin checkers for core language features +//===----------------------------------------------------------------------===// + +let ParentPackage = CoreOptIn in { + +def EnumCastOutOfRangeChecker : Checker<"EnumCastOutOfRange">, + HelpText<"Check integer to enumeration casts for out of range values">, + Documentation<HasDocumentation>; + +} // end "optin.core" + //===----------------------------------------------------------------------===// // Unix API checkers. //===----------------------------------------------------------------------===// @@ -763,10 +776,6 @@ def DeleteWithNonVirtualDtorChecker : Checker<"DeleteWithNonVirtualDtor">, "destructor in their base class">, Documentation<HasDocumentation>; -def EnumCastOutOfRangeChecker : Checker<"EnumCastOutOfRange">, - HelpText<"Check integer to enumeration casts for out of range values">, - Documentation<HasDocumentation>; - def IteratorModeling : Checker<"IteratorModeling">, HelpText<"Models iterators of C++ containers">, Dependencies<[ContainerModeling]>, diff --git a/clang/test/Analysis/enum-cast-out-of-range.c b/clang/test/Analysis/enum-cast-out-of-range.c index 3282cba653d7125..328b8b28ca70003 100644 --- a/clang/test/Analysis/enum-cast-out-of-range.c +++ b/clang/test/Analysis/enum-cast-out-of-range.c @@ -1,5 +1,5 @@ // RUN: %clang_analyze_cc1 \ -// RUN: -analyzer-checker=core,alpha.cplusplus.EnumCastOutOfRange \ +// RUN: -analyzer-checker=core,optin.core.EnumCastOutOfRange \ // RUN: -verify %s enum En_t { diff --git a/clang/test/Analysis/enum-cast-out-of-range.cpp b/clang/test/Analysis/enum-cast-out-of-range.cpp index abc1431e5be140f..33790f726c5ff8a 100644 --- a/clang/test/Analysis/enum-cast-out-of-range.cpp +++ b/clang/test/Analysis/enum-cast-out-of-range.cpp @@ -1,5 +1,5 @@ // RUN: %clang_analyze_cc1 \ -// RUN: -analyzer-checker=core,alpha.cplusplus.EnumCastOutOfRange \ +// RUN: -analyzer-checker=core,optin.core.EnumCastOutOfRange \ // RUN: -std=c++11 -verify %s enum unscoped_unspecified_t { @@ -215,3 +215,14 @@ void empty_enums_init_with_zero_should_not_warn() { ignore_unused(eu, ef, efu); } + +//Test the example from checkers.rst: +enum WidgetKind { A=1, B, C, X=99 }; + +void foo() { + WidgetKind c = static_cast<WidgetKind>(3); // OK + WidgetKind x = static_cast<WidgetKind>(99); // OK + WidgetKind d = static_cast<WidgetKind>(4); // expected-warning {{The value provided to the cast expression is not in the valid range of values for the enum}} + + ignore_unused(c, x, d); +} diff --git a/clang/www/analyzer/alpha_checks.html b/clang/www/analyzer/alpha_checks.html index 181ce1b9de591b3..a00e330a4e99579 100644 --- a/clang/www/analyzer/alpha_checks.html +++ b/clang/www/analyzer/alpha_checks.html @@ -350,25 +350,6 @@ <h3 id="cplusplus_alpha_checkers">C++ Alpha Checkers</h3> } </pre></div></div></td></tr> -<tr><td><a id="alpha.cplusplus.EnumCastOutOfRange"><div class="namedescr expandable"><span class="name"> -alpha.cplusplus.EnumCastOutOfRange</span><span class="lang"> -(C++)</span><div class="descr"> - Check for integer to enumeration casts that could result in undefined values. -</div></div></a></td> - <td><div class="exampleContainer expandable"> - <div class="example"><pre> -enum TestEnum { - A = 0 -}; - -void foo() { - TestEnum t = static_cast<TestEnum>(-1); - // warn: the value provided to the cast expression is not in - the valid range of values for the enum -} -</pre></div></div></td></tr> - - <tr><td><a id="alpha.cplusplus.InvalidatedIterator"><div class="namedescr expandable"><span class="name"> alpha.cplusplus.InvalidatedIterator</span><span class="lang"> (C++)</span><div class="descr"> `````````` </details> https://github.com/llvm/llvm-project/pull/67157 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
