Only apply const rewrite for lvalue context

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -3019,28 +3019,28 @@ bool Converter::ConvertIncAndDec(clang::UnaryOperator *expr) {
   auto *sub_expr = expr->getSubExpr();
   switch (opcode) {
   case clang::UO_PostInc: {
-    PushExprKind push(*this, ExprKind::RValue);
+    PushExprKind push(*this, ExprKind::LValue);
     Convert(sub_expr);
     StrCat(".postfix_inc()");
     SetFresh();
     return true;
   }
   case clang::UO_PostDec: {
-    PushExprKind push(*this, ExprKind::RValue);
+    PushExprKind push(*this, ExprKind::LValue);
     Convert(sub_expr);
     StrCat(".postfix_dec()");
     SetFresh();
     return true;
   }
   case clang::UO_PreInc: {
-    PushExprKind push(*this, ExprKind::RValue);
+    PushExprKind push(*this, ExprKind::LValue);
     Convert(sub_expr);
     StrCat(".prefix_inc()");
     SetFresh();
     return true;
   }
   case clang::UO_PreDec: {
-    PushExprKind push(*this, ExprKind::RValue);
+    PushExprKind push(*this, ExprKind::LValue);
     Convert(sub_expr);
     StrCat(".prefix_dec()");
     SetFresh();
@@ -3383,7 +3383,8 @@ bool Converter::VisitMemberExpr(clang::MemberExpr *expr) {
     auto *base = expr->getBase();
     auto object_type = expr->isArrow() ? base->getType()->getPointeeType()
                                        : base->getType().getNonReferenceType();
-    if (!clang::isa<clang::CXXThisExpr>(base->IgnoreParenImpCasts()) &&
+    if (!isRValue() &&
+        !clang::isa<clang::CXXThisExpr>(base->IgnoreParenImpCasts()) &&
         object_type.isConstQualified()) {
       if (isAddrOf()) {
         StrCat(std::format("(&raw const {}).cast_mut()", str));

tests/unit/out/unsafe/class.rs

@@ -134,7 +134,7 @@ unsafe fn main_0() -> i32 {
     assert!((unsafe { Counter::operator_eq(&mut *(&raw const c1).cast_mut(), &c2,) }));
     assert!((unsafe { Counter::operator_eq(&mut *(&raw const c2).cast_mut(), &c1,) }));
     assert!(((c1.calls) == (3)));
-    assert!(((*(&raw const c2.calls).cast_mut()) == (2)));
+    assert!(((c2.calls) == (2)));
     return 0;
 }
 pub unsafe fn __cpp2rust_init_globals() {}

tests/unit/out/unsafe/copy_ctor.rs

@@ -244,7 +244,7 @@ unsafe fn main_0() -> i32 {
     let ct: Tracked = <Tracked>::default();
     let mut t3: Tracked = Tracked::copy_from({ &ct });
     (unsafe { touch_1((&ct as *const Tracked)) });
-    assert!(((*(&raw const ct.copied_from).cast_mut()) == (2)));
+    assert!(((ct.copied_from) == (2)));
     return 0;
 }
 pub unsafe fn __cpp2rust_init_globals() {