[analyzer] Ignore system headers in WebKit checkers. (#91103)

Author: rniwa

clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp

@@ -150,6 +150,9 @@ class UncountedCallArgsChecker
   bool shouldSkipCall(const CallExpr *CE) const {
     const auto *Callee = CE->getDirectCallee();
 
+    if (BR->getSourceManager().isInSystemHeader(CE->getExprLoc()))
+      return true;
+
     if (Callee && TFA.isTrivial(Callee))
       return true;
 

clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedLocalVarsChecker.cpp

@@ -230,6 +230,9 @@ class UncountedLocalVarsChecker
     if (!V->isLocalVarDecl())
       return true;
 
+    if (BR->getSourceManager().isInSystemHeader(V->getLocation()))
+      return true;
+
     return false;
   }
 

clang/test/Analysis/Checkers/WebKit/mock-system-header.h

@@ -0,0 +1,17 @@
+#pragma clang system_header
+
+template <typename T, typename CreateFunction>
+void callMethod(CreateFunction createFunction) {
+  createFunction()->method();
+}
+
+template <typename T, typename CreateFunction>
+inline void localVar(CreateFunction createFunction) {
+  T* obj = createFunction();
+  obj->method();
+}
+
+template <typename T>
+struct MemberVariable {
+    T* obj { nullptr };
+};

clang/test/Analysis/Checkers/WebKit/uncounted-local-vars.cpp

@@ -1,6 +1,7 @@
 // RUN: %clang_analyze_cc1 -analyzer-checker=alpha.webkit.UncountedLocalVarsChecker -verify %s
 
 #include "mock-types.h"
+#include "mock-system-header.h"
 
 void someFunction();
 
@@ -187,3 +188,13 @@ void bar() {
 }
 
 } // namespace ignore_for_if
+
+namespace ignore_system_headers {
+
+RefCountable *provide_ref_ctnbl();
+
+void system_header() {
+  localVar<RefCountable>(provide_ref_ctnbl);
+}
+
+} // ignore_system_headers

clang/test/Analysis/Checkers/WebKit/uncounted-members.cpp

@@ -1,6 +1,7 @@
 // RUN: %clang_analyze_cc1 -analyzer-checker=webkit.NoUncountedMemberChecker -verify %s
 
 #include "mock-types.h"
+#include "mock-system-header.h"
 
 namespace members {
   struct Foo {
@@ -50,3 +51,12 @@ namespace ignore_unions {
 
   void forceTmplToInstantiate(RefPtr<RefCountable>) {}
 }
+
+namespace ignore_system_header {
+
+void foo(RefCountable* t) {
+  MemberVariable<RefCountable> var { t };
+  var.obj->method();
+}
+
+} // ignore_system_header

clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp

@@ -1,6 +1,7 @@
 // RUN: %clang_analyze_cc1 -analyzer-checker=alpha.webkit.UncountedCallArgsChecker -verify %s
 
 #include "mock-types.h"
+#include "mock-system-header.h"
 
 void WTFBreakpointTrap();
 void WTFCrashWithInfo(int, const char*, const char*, int);
@@ -147,6 +148,7 @@ class RefCounted {
   void ref() const;
   void deref() const;
 
+  void method();
   void someFunction();
   int otherFunction();
 
@@ -399,3 +401,7 @@ void someFunction(const RefCounted&);
 void test2() {
     someFunction(*object());
 }
+
+void system_header() {
+  callMethod<RefCountable>(object);
+}