[clang] [analyzer] Conversion to CheckerFamily: MallocChecker (PR #147080)

[Balazs Benics via cfe-commits]

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=?utf-8?q?Donát?= Nagy <donat.nagy at ericsson.com>,
=?utf-8?q?Donát?= Nagy <donat.nagy at ericsson.com>,
=?utf-8?q?Donát?= Nagy <donat.nagy at ericsson.com>,
=?utf-8?q?Donát?= Nagy <donat.nagy at ericsson.com>,
=?utf-8?q?Donát?= Nagy <donat.nagy at ericsson.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/147080 at github.com>


================
@@ -333,11 +333,55 @@ template <typename T> static bool isStandardNewDelete(const T &FD) {
   return isStandardDelete(FD) || isStandardNew(FD);
 }
 
+namespace {
+
 //===----------------------------------------------------------------------===//
-// Definition of the MallocChecker class.
+// Utility classes that provide access to the bug types and can model that some
+// of the bug types are shared by multiple checker frontends.
 //===----------------------------------------------------------------------===//
 
-namespace {
+#define BUGTYPE_PROVIDER(NAME, DEF)                                            \
+  struct NAME : virtual public CheckerFrontend {                               \
+    BugType NAME##Bug{this, DEF, categories::MemoryError};                     \
+  };
+
+BUGTYPE_PROVIDER(DoubleFree, "Double free")
+// TODO: Remove DoubleDelete as a separate bug type and when it would be
+// emitted, emit DoubleFree reports instead. (Note that DoubleFree is already
+// used for all allocation families, not just malloc/free.)
+BUGTYPE_PROVIDER(DoubleDelete, "Double delete")
+
+struct Leak : virtual public CheckerFrontend {
+  // Leaks should not be reported if they are post-dominated by a sink:
+  // (1) Sinks are higher importance bugs.
+  // (2) NoReturnFunctionChecker uses sink nodes to represent paths ending
+  //     with __noreturn functions such as assert() or exit(). We choose not
+  //     to report leaks on such paths.
+  BugType LeakBug{this, "Memory leak", categories::MemoryError,
+                  /*SuppressOnSink=*/true};
+};
+
+BUGTYPE_PROVIDER(UseFree, "Use-after-free")
+BUGTYPE_PROVIDER(BadFree, "Bad free")
+BUGTYPE_PROVIDER(FreeAlloca, "Free 'alloca()'")
+BUGTYPE_PROVIDER(MismatchedDealloc, "Bad deallocator")
+BUGTYPE_PROVIDER(OffsetFree, "Offset free")
+BUGTYPE_PROVIDER(UseZeroAllocated, "Use of zero allocated")
+
+template <typename... BT_PROVIDERS>
+struct DynMemFrontend : virtual public CheckerFrontend, public BT_PROVIDERS... {
+  template <typename T> const T *getAs() const {
+    if constexpr (std::is_same_v<T, CheckerFrontend>)
+      return static_cast<const T *>(this);
+    if constexpr ((std::is_same_v<T, BT_PROVIDERS> || ...))
+      return static_cast<const T *>(this);
----------------
steakhal wrote:

```suggestion
    if constexpr (std::is_same_v<T, CheckerFrontend> || (std::is_same_v<T, BT_PROVIDERS> || ...))
      return static_cast<const T *>(this);
```

https://github.com/llvm/llvm-project/pull/147080