Avoid moves when creating variadic pointer arguments (#233)

Author: lucic71

cpp2rust/converter/models/converter_refcount.cpp

@@ -1827,7 +1827,13 @@ bool ConverterRefCount::VisitImplicitValueInitExpr(
   return Converter::VisitImplicitValueInitExpr(expr);
 }
 
-void ConverterRefCount::ConvertVariadicArg(clang::Expr *arg) { Convert(arg); }
+void ConverterRefCount::ConvertVariadicArg(clang::Expr *arg) {
+  if (arg->getType()->isPointerType()) {
+    StrCat(ConvertFreshPointer(arg));
+    return;
+  }
+  Convert(arg);
+}
 
 bool ConverterRefCount::VisitVAArgExpr(clang::VAArgExpr *expr) {
   auto va_list_expr = expr->getSubExpr();

tests/unit/out/refcount/va_arg_non_primitive_ptrs.rs

@@ -109,7 +109,12 @@ fn main_0() -> i32 {
     );
     assert!((((!((*s.borrow()).is_null())) as i32) != 0));
     assert!(
-        (((({ dispatch_0((opt::OPT_FILE as i32), &[(libcc2rs::cout()).into(),]) }) == 1) as i32)
+        (((({
+            dispatch_0(
+                (opt::OPT_FILE as i32),
+                &[((libcc2rs::cout()).clone()).into()],
+            )
+        }) == 1) as i32)
             != 0)
     );
     assert!(

tests/unit/out/refcount/va_arg_printf.rs

@@ -24,6 +24,16 @@ pub fn logf_1(fmt: Ptr<u8>, __args: &[VaArg]) -> i32 {
     ));
     return (*result.borrow());
 }
+pub fn lenf_2(fmt: Ptr<u8>, __args: &[VaArg]) -> i32 {
+    let fmt: Value<Ptr<u8>> = Rc::new(RefCell::new(fmt));
+    let ap: Value<VaList> = Rc::new(RefCell::new(VaList::default()));
+    (*ap.borrow_mut()) = VaList::new(__args);
+    let s: Value<Ptr<u8>> = Rc::new(RefCell::new(((*ap.borrow_mut()).arg::<Ptr<u8>>()).clone()));
+    let result: Value<i32> = Rc::new(RefCell::new(
+        ((*s.borrow()).to_string_iterator().count() as i32),
+    ));
+    return (*result.borrow());
+}
 pub fn main() {
     std::process::exit(main_0());
 }
@@ -50,5 +60,30 @@ fn main_0() -> i32 {
         }) == 3) as i32)
             != 0)
     );
+    assert!(
+        (((({
+            lenf_2(
+                Ptr::from_string_literal(b"%s"),
+                &[((*dummy.borrow()).clone()).into()],
+            )
+        }) == 5) as i32)
+            != 0)
+    );
+    assert!(
+        (((({
+            lenf_2(
+                Ptr::from_string_literal(b"%s"),
+                &[
+                    (if ((((*dummy.borrow()).offset((0) as isize).read()) as i32) != 0) {
+                        (*dummy.borrow()).clone()
+                    } else {
+                        Ptr::from_string_literal(b"")
+                    })
+                    .into(),
+                ],
+            )
+        }) == 5) as i32)
+            != 0)
+    );
     return 0;
 }

tests/unit/out/unsafe/va_arg_printf.rs

@@ -16,6 +16,13 @@ pub unsafe fn logf_1(mut fmt: *const libc::c_char, __args: &[VaArg]) -> i32 {
     let mut result: i32 = (unsafe { logf_impl_0(fmt, ap) });
     return result;
 }
+pub unsafe fn lenf_2(mut fmt: *const libc::c_char, __args: &[VaArg]) -> i32 {
+    let mut ap: VaList = VaList::default();
+    ap = VaList::new(__args);
+    let mut s: *const libc::c_char = ap.arg::<*const libc::c_char>();
+    let mut result: i32 = (libc::strlen(s) as i32);
+    return result;
+}
 pub fn main() {
     unsafe {
         std::process::exit(main_0() as i32);
@@ -41,5 +48,24 @@ unsafe fn main_0() -> i32 {
         }) == (3)) as i32)
             != 0)
     );
+    assert!(
+        ((((unsafe { lenf_2((c"%s".as_ptr().cast_mut()).cast_const(), &[(dummy).into(),]) }) == (5))
+            as i32)
+            != 0)
+    );
+    assert!(
+        ((((unsafe {
+            lenf_2(
+                (c"%s".as_ptr().cast_mut()).cast_const(),
+                &[(if (((*dummy.offset((0) as isize)) as i32) != 0) {
+                    dummy
+                } else {
+                    (c"".as_ptr().cast_mut() as *const libc::c_char)
+                })
+                .into()],
+            )
+        }) == (5)) as i32)
+            != 0)
+    );
     return 0;
 }

tests/unit/va_arg_printf.c

@@ -15,9 +15,20 @@ int logf(const char *fmt, ...) {
   return result;
 }
 
+int lenf(const char *fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  const char *s = va_arg(ap, const char *);
+  int result = (int)strlen(s);
+  va_end(ap);
+  return result;
+}
+
 int main() {
   const char *dummy = "dummy";
   assert(logf("hello %d %d", 10, strlen(dummy)) == 15);
   assert(logf("x %d %d", 1, 2) == 3);
+  assert(lenf("%s", dummy) == 5);
+  assert(lenf("%s", dummy[0] ? dummy : "") == 5);
   return 0;
 }