Fix assignments that produce values (#158)

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -2108,13 +2108,17 @@ void Converter::ConvertBinaryOperator(clang::BinaryOperator *expr) {
     if (expr->isCompoundAssignmentOp() &&
         expr->getLHS()->getType()->isPointerType() &&
         expr->getRHS()->getType()->isIntegralOrEnumerationType()) {
+      PushBrace brace(*this, !isVoid());
       Convert(lhs);
       StrCat(token::kAssign);
       {
         PushParen paren(*this);
         ConvertUnsignedArithOperand(lhs, type);
       }
       ConvertUnsignedArithBinaryOperator(expr, rhs);
+      if (!isVoid()) {
+        StrCat(token::kSemiColon, ConvertRValue(lhs));
+      }
     } else {
       ConvertAssignment(lhs, rhs, opcode_as_string);
     }
@@ -3030,7 +3034,8 @@ bool Converter::VisitSwitchStmt(clang::SwitchStmt *stmt) {
   if (has_fallthrough) {
     StrCat("match", ToString(stmt->getCond()));
   } else {
-    StrCat(std::format("let __match_cond = {};", ToString(stmt->getCond())));
+    StrCat(
+        std::format("let __match_cond = {};", ConvertRValue(stmt->getCond())));
     StrCat("match __match_cond");
   }
 

cpp2rust/converter/models/converter_refcount.cpp

@@ -1879,7 +1879,7 @@ void ConverterRefCount::ConvertAssignment(clang::Expr *lhs, clang::Expr *rhs,
   }
 
   if (isRValue()) {
-    StrCat(token::kSemiColon, ConvertRValue(lhs));
+    StrCat(token::kSemiColon, ConvertFreshRValue(lhs));
   }
 }
 

tests/unit/assign_as_value.c

@@ -0,0 +1,20 @@
+#include <assert.h>
+
+int main(void) {
+  char buf[2];
+  char *p = buf, *q;
+  q = p += 1;
+  assert(q == buf + 1);
+
+  char out;
+  switch (out = 'x') {
+  case 'x':
+    assert(1);
+    break;
+  default:
+    assert(0);
+    break;
+  }
+  assert(out == 'x');
+  return 0;
+}

tests/unit/out/refcount/assign_as_value.rs

@@ -0,0 +1,48 @@
+extern crate libcc2rs;
+use libcc2rs::*;
+use std::cell::RefCell;
+use std::collections::BTreeMap;
+use std::io::prelude::*;
+use std::io::{Read, Seek, Write};
+use std::os::fd::AsFd;
+use std::rc::{Rc, Weak};
+pub fn main() {
+    std::process::exit(main_0());
+}
+fn main_0() -> i32 {
+    let buf: Value<Box<[u8]>> = Rc::new(RefCell::new(
+        (0..2).map(|_| <u8>::default()).collect::<Box<[u8]>>(),
+    ));
+    let p: Value<Ptr<u8>> = Rc::new(RefCell::new((buf.as_pointer() as Ptr<u8>)));
+    let q: Value<Ptr<u8>> = Rc::new(RefCell::new(Ptr::<u8>::null()));
+    (*q.borrow_mut()) = {
+        (*p.borrow_mut()) += 1;
+        (*p.borrow()).clone()
+    };
+    assert!(
+        ((({
+            let _lhs = (*q.borrow()).clone();
+            _lhs == (buf.as_pointer() as Ptr<u8>).offset((1) as isize)
+        }) as i32)
+            != 0)
+    );
+    let out: Value<u8> = <Value<u8>>::default();
+    'switch: {
+        let __match_cond = (({
+            (*out.borrow_mut()) = (('x' as i32) as u8);
+            (*out.borrow())
+        }) as i32);
+        match __match_cond {
+            v if v == ('x' as i32) => {
+                assert!((1 != 0));
+                break 'switch;
+            }
+            _ => {
+                assert!((0 != 0));
+                break 'switch;
+            }
+        }
+    };
+    assert!((((((*out.borrow()) as i32) == ('x' as i32)) as i32) != 0));
+    return 0;
+}

tests/unit/out/unsafe/assign_as_value.rs

@@ -0,0 +1,42 @@
+extern crate libc;
+use libc::*;
+extern crate libcc2rs;
+use libcc2rs::*;
+use std::collections::BTreeMap;
+use std::io::{Read, Seek, Write};
+use std::os::fd::{AsFd, FromRawFd, IntoRawFd};
+use std::rc::Rc;
+pub fn main() {
+    unsafe {
+        std::process::exit(main_0() as i32);
+    }
+}
+unsafe fn main_0() -> i32 {
+    let mut buf: [u8; 2] = [0_u8; 2];
+    let mut p: *mut u8 = buf.as_mut_ptr();
+    let mut q: *mut u8 = std::ptr::null_mut();
+    q = {
+        p = (p).wrapping_add(1 as i32 as usize);
+        p
+    };
+    assert!(((((q) == (buf.as_mut_ptr().offset((1) as isize))) as i32) != 0));
+    let mut out: u8 = 0_u8;
+    'switch: {
+        let __match_cond = (({
+            out = (('x' as i32) as u8);
+            out
+        }) as i32);
+        match __match_cond {
+            v if v == ('x' as i32) => {
+                assert!((1 != 0));
+                break 'switch;
+            }
+            _ => {
+                assert!((0 != 0));
+                break 'switch;
+            }
+        }
+    };
+    assert!(((((out as i32) == ('x' as i32)) as i32) != 0));
+    return 0;
+}

tests/unit/out/unsafe/union_tagged_struct_arms.rs

@@ -73,7 +73,7 @@ pub fn main() {
     }
 }
 unsafe fn main_0() -> i32 {
-    static mut items_0: [*mut u8; 3] = unsafe {
+    static mut items_4: [*mut u8; 3] = unsafe {
         [
             b"a\0".as_ptr().cast_mut(),
             b"b\0".as_ptr().cast_mut(),
@@ -83,7 +83,7 @@ unsafe fn main_0() -> i32 {
     let mut p_list: Branch = <Branch>::default();
     p_list.choice = Choice::C_LIST;
     p_list.index = 0;
-    p_list.v.list.items = items_0.as_mut_ptr();
+    p_list.v.list.items = items_4.as_mut_ptr();
     p_list.v.list.count = 3_i64;
     p_list.v.list.cursor = 1_i64;
     assert!(((((p_list.v.list.count) == (3_i64)) as i32) != 0));