=?utf-8?q?Donát?= Nagy <donat.n...@ericsson.com>,NagyDonat <donat.n...@ericsson.com> Message-ID: In-Reply-To: <llvm.org/llvm/llvm-project/pull/83...@github.com>
================ @@ -27,20 +27,48 @@ class IdentifierInfo; namespace clang { namespace ento { - -enum CallDescriptionFlags : unsigned { - CDF_None = 0, - - /// Describes a C standard function that is sometimes implemented as a macro - /// that expands to a compiler builtin with some __builtin prefix. - /// The builtin may as well have a few extra arguments on top of the requested - /// number of arguments. - CDF_MaybeBuiltin = 1 << 0, -}; - -/// This class represents a description of a function call using the number of -/// arguments and the name of the function. +/// A `CallDescription` is a pattern that can be used to _match_ calls +/// based on the qualified name and the argument/parameter counts. class CallDescription { +public: + enum class Mode { + /// Match calls to functions from the C standard library. On some platforms + /// some functions may be implemented as macros that expand to calls to + /// built-in variants of the given functions, so in this mode we use some + /// heuristics to recognize these implementation-defined variants: + /// - We also accept calls where the name is derived from the specified + /// name by adding "__builtin" or similar prefixes/suffixes. + /// - We also accept calls where the number of arguments or parameters is + /// greater than the specified value. + /// For the exact heuristics, see CheckerContext::isCLibraryFunction(). + /// Note that functions whose declaration context is not a TU (e.g. + /// methods, functions in namespaces) are not accepted as C library + /// functions. + /// FIXME: If I understand it correctly, this discards calls where C++ code + /// refers a C library function through the namespace `std::` via headers + /// like <cstdlib>. + CLibrary, ---------------- NagyDonat wrote: > I saw cases at MallocChecker where it is not used, then it should be used in > these cases too. In fact that was the original reason why I started to work on `CallDescription`s: there was an open source bug report (https://github.com/llvm/llvm-project/issues/81597) where MallocChecker recognized a C++ method named `free` as if it was the well-known function `free`. Now I realize that it would've been possible to resolve that bug by just adding `CDF_MaybeBuiltin` to the `CallDescription` for `free`, but I was misled by the name `CDF_MaybeBuiltin` and thought that I need to introduce a new matching mode that says "_must_ be function". After merging this commit, I'll quickly do a followup commit that fixes `MallocChecker`, but then I'll continue with cleaning up the other checkers as well. https://github.com/llvm/llvm-project/pull/83432 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits