[analyzer] CStringChecker: bail out when arguments of copy function are not pointers

Author: guillem-bartrina-sonarsource

clang/lib/StaticAnalyzer/Checkers/CStringChecker.cpp

@@ -672,6 +672,10 @@ ProgramStateRef CStringChecker::CheckOverlap(CheckerContext &C,
 
   ProgramStateRef stateTrue, stateFalse;
 
+  if (!First.Expression->getType()->isAnyPointerType() ||
+      !Second.Expression->getType()->isAnyPointerType())
+    return state;
+
   // Assume different address spaces cannot overlap.
   if (First.Expression->getType()->getPointeeType().getAddressSpace() !=
       Second.Expression->getType()->getPointeeType().getAddressSpace())

clang/test/Analysis/buffer-overlap.c

@@ -96,3 +96,19 @@ void test_snprintf6() {
   char b[4] = {0};
   snprintf(a, sizeof(a), "%s", b); // no-warning
 }
+
+
+void memcpy(int dst, int src, size_t size); // expected-warning{{incompatible redeclaration of library function 'memcpy'}} expected-note{{'memcpy' is a builtin with type 'void *(void *, const void *, __size_t)' (aka 'void *(void *, const void *, unsigned long)')}}
+void test_memcpy_proxy() {
+  memcpy(42, 42, 42);
+}
+
+void strcpy(int dst, char *src); // expected-warning{{incompatible redeclaration of library function 'strcpy'}} expected-note{{'strcpy' is a builtin with type 'char *(char *, const char *)'}}
+void test_strcpy_proxy() {
+  strcpy(42, (char *)42);
+}
+
+void strxfrm(int dst, char *src, size_t size); // expected-warning{{incompatible redeclaration of library function 'strxfrm'}} expected-note{{'strxfrm' is a builtin with type '__size_t (char *, const char *, __size_t)' (aka 'unsigned long (char *, const char *, unsigned long)')}}
+void test_strxfrm_proxy() {
+  strxfrm(42, (char *)42, 42);
+}