Provide a source location when analysis finds constness is lost

Author: tautschnig

src/analyses/does_remove_const.cpp

@@ -31,7 +31,7 @@ does_remove_constt::does_remove_constt(
 
 /// A naive analysis to look for casts that remove const-ness from pointers.
 /// \return Returns true if the program contains a const-removing cast
-bool does_remove_constt::operator()() const
+std::pair<bool, source_locationt> does_remove_constt::operator()() const
 {
   for(const goto_programt::instructiont &instruction :
     goto_program.instructions)
@@ -49,16 +49,16 @@ bool does_remove_constt::operator()() const
     // const that the lhs
     if(!does_type_preserve_const_correctness(&lhs_type, &rhs_type))
     {
-      return true;
+      return {true, assign.find_source_location()};
     }
 
     if(does_expr_lose_const(assign.rhs()))
     {
-      return true;
+      return {true, assign.rhs().find_source_location()};
     }
   }
 
-  return false;
+  return {false, source_locationt()};
 }
 
 /// Search the expression tree to look for any children that have the same base

src/analyses/does_remove_const.h

@@ -22,7 +22,7 @@ class does_remove_constt
 {
 public:
   does_remove_constt(const goto_programt &goto_program, const namespacet &ns);
-  bool operator()() const;
+  std::pair<bool, source_locationt>  operator()() const;
 
 private:
   bool does_expr_lose_const(const exprt &expr) const;

src/goto-programs/remove_function_pointers.cpp

@@ -285,9 +285,11 @@ void remove_function_pointerst::remove_function_pointer(
   const exprt &pointer=function.op0();
   remove_const_function_pointerst::functionst functions;
   does_remove_constt const_removal_check(goto_program, ns);
-  if(const_removal_check())
+  const auto does_remove_const = const_removal_check();
+  if(does_remove_const.first)
   {
-    warning() << "Cast from const to non-const pointer found, only worst case"
+    warning().source_location = does_remove_const.second;
+    warning() << "cast from const to non-const pointer found, only worst case"
               << " function pointer removal will be done." << eom;
     found_functions=false;
   }