Add void cast on function ptr unused arg (#241)

Author: lucic71

cpp2rust/converter/converter.h

@@ -274,6 +274,13 @@ class Converter : public clang::RecursiveASTVisitor<Converter> {
   // Option<fn> implements Copy
   virtual bool FunctionPointerImplementsCopy() const { return true; }
 
+  bool TypeIsCopyable(clang::QualType ty) const {
+    if (ty->isFunctionPointerType() || ty->isFunctionType()) {
+      return FunctionPointerImplementsCopy();
+    }
+    return ty->isIntegerType();
+  }
+
   virtual void ConvertPrintf(clang::CallExpr *expr);
 
   void ConvertVAArgCall(clang::CallExpr *expr);

cpp2rust/converter/converter_lib.cpp

@@ -1104,9 +1104,4 @@ ConstCastType GetConstCastType(clang::QualType to, clang::QualType from) {
   }
 }
 
-bool TypeIsCopyable(clang::QualType ty) {
-  return ty->isIntegerType() || ty->isFunctionPointerType() ||
-         ty->isFunctionType();
-}
-
 } // namespace cpp2rust

cpp2rust/converter/converter_lib.h

@@ -223,6 +223,4 @@ enum class ConstCastType {
 
 ConstCastType GetConstCastType(clang::QualType to, clang::QualType from);
 
-bool TypeIsCopyable(clang::QualType ty);
-
 } // namespace cpp2rust

tests/unit/out/refcount/va_arg_fn_ptr.rs

@@ -42,6 +42,15 @@ pub fn apply_binary_4(a: i32, b: i32, __args: &[VaArg]) -> i32 {
     ));
     return (*result.borrow());
 }
+pub fn not_supported_5(ctx: AnyPtr, fn_: FnPtr<fn(i32) -> i32>, extra: AnyPtr) -> i32 {
+    let ctx: Value<AnyPtr> = Rc::new(RefCell::new(ctx));
+    let fn_: Value<FnPtr<fn(i32) -> i32>> = Rc::new(RefCell::new(fn_));
+    let extra: Value<AnyPtr> = Rc::new(RefCell::new(extra));
+    (*ctx.borrow()).clone();
+    (*fn_.borrow()).clone();
+    (*extra.borrow()).clone();
+    return -3_i32;
+}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -61,5 +70,14 @@ fn main_0() -> i32 {
             as i32)
             != 0)
     );
+    let dummy: Value<i32> = Rc::new(RefCell::new(0));
+    assert!(
+        (((({
+            let _ctx: AnyPtr = ((dummy.as_pointer()) as Ptr<i32>).to_any();
+            let _extra: AnyPtr = ((dummy.as_pointer()) as Ptr<i32>).to_any();
+            not_supported_5(_ctx, FnPtr::<fn(i32) -> i32>::new(square_0), _extra)
+        }) == -3_i32) as i32)
+            != 0)
+    );
     return 0;
 }

tests/unit/out/refcount/void_cast.rs

@@ -104,11 +104,11 @@ fn main_0() -> i32 {
     }));
     assert!(((*err.borrow()) == 7));
     assert!(((*chosen.borrow()) == 123));
-    bump_and_return_4;
+    bump_and_return_4.clone();
     assert!(((*side_effect_counter_3.with(Value::clone).borrow()) == 2));
-    (FnPtr::<fn() -> i32>::new(bump_and_return_4));
+    (FnPtr::<fn() -> i32>::new(bump_and_return_4)).clone();
     assert!(((*side_effect_counter_3.with(Value::clone).borrow()) == 2));
-    ((FnPtr::<fn() -> i32>::new(bump_and_return_4)).cast::<fn() -> i32>(None));
+    ((FnPtr::<fn() -> i32>::new(bump_and_return_4)).cast::<fn() -> i32>(None)).clone();
     assert!(((*side_effect_counter_3.with(Value::clone).borrow()) == 2));
     let storage: Value<i32> = Rc::new(RefCell::new(11));
     let p: Value<Ptr<i32>> = Rc::new(RefCell::new((storage.as_pointer())));

tests/unit/out/unsafe/va_arg_fn_ptr.rs

@@ -35,6 +35,16 @@ pub unsafe fn apply_binary_4(mut a: i32, mut b: i32, __args: &[VaArg]) -> i32 {
     let mut result: i32 = (unsafe { (fn_).unwrap()(a, b) });
     return result;
 }
+pub unsafe fn not_supported_5(
+    mut ctx: *mut ::libc::c_void,
+    mut fn_: Option<unsafe fn(i32) -> i32>,
+    mut extra: *mut ::libc::c_void,
+) -> i32 {
+    &(ctx);
+    &(fn_);
+    &(extra);
+    return -3_i32;
+}
 pub fn main() {
     unsafe {
         std::process::exit(main_0() as i32);
@@ -78,5 +88,16 @@ unsafe fn main_0() -> i32 {
         }) == (7)) as i32)
             != 0)
     );
+    let mut dummy: i32 = 0;
+    assert!(
+        ((((unsafe {
+            let _ctx: *mut ::libc::c_void =
+                ((&mut dummy as *mut i32) as *mut i32 as *mut ::libc::c_void);
+            let _extra: *mut ::libc::c_void =
+                ((&mut dummy as *mut i32) as *mut i32 as *mut ::libc::c_void);
+            not_supported_5(_ctx, Some(square_0), _extra)
+        }) == (-3_i32)) as i32)
+            != 0)
+    );
     return 0;
 }

tests/unit/va_arg_fn_ptr.c

@@ -26,9 +26,18 @@ int apply_binary(int a, int b, ...) {
   return result;
 }
 
+static int not_supported(void *ctx, unary fn, void *extra) {
+  (void)ctx;
+  (void)fn;
+  (void)extra;
+  return -3;
+}
+
 int main() {
   assert(apply_unary(5, square) == 25);
   assert(apply_unary(7, negate) == -7);
   assert(apply_binary(3, 4, add) == 7);
+  int dummy = 0;
+  assert(not_supported(&dummy, square, &dummy) == -3);
   return 0;
 }