C++: Remove potential FPs from cpp/integer-multiplication-cast-to-long in BMN

cpp/ql/src/Likely Bugs/Arithmetic/IntMultToLong.ql

@@ -177,6 +177,12 @@ predicate overflows(MulExpr me, Type t) {
   )
 }
 
+predicate buildModeNoneIntLongConversion(IntType argType, LongType resultType) {
+  exists(argType) and
+  exists(resultType) and
+  exists(Compilation c | c.buildModeNone())
+}
+
 from MulExpr me, Type t1, Type t2
 where
   t1 = me.getType().getUnderlyingType() and
@@ -218,7 +224,10 @@ where
   // only report if we cannot prove that the result of the
   // multiplication will be less (resp. greater) than the
   // maximum (resp. minimum) number we can compute.
-  overflows(me, t1)
+  overflows(me, t1) and
+  // In build mode none, many conversions from integer to long are caused by incorrect types,
+  // so exclude those results
+  not buildModeNoneIntLongConversion(t1, t2)
 select me,
   "Multiplication result may overflow '" + me.getType().toString() + "' before it is converted to '"
     + me.getFullyConverted().getType().toString() + "'."

cpp/ql/test/query-tests/Likely Bugs/Arithmetic/IntMultToLongBuildless/IntMulToLong.c

@@ -5,6 +5,6 @@ int f();
 void test() {
   int i = f();
   unsigned u = i;
-  long j = i * i; // BAD (FP)
-  unsigned long k = u * u; // BAD (FP)
+  long j = i * i; // GOOD: build mode none
+  unsigned long k = u * u; // GOOD: build mode none
 }

cpp/ql/test/query-tests/Likely Bugs/Arithmetic/IntMultToLongBuildless/IntMultToLong.expected

@@ -1,2 +0,0 @@
-| IntMulToLong.c:8:12:8:16 | ... * ... | Multiplication result may overflow 'int' before it is converted to 'long'. |
-| IntMulToLong.c:9:21:9:25 | ... * ... | Multiplication result may overflow 'unsigned int' before it is converted to 'unsigned long'. |