[arithmetic_side_effects] Fix rust-lang#10792

c410-f3r · May 17, 2023 · f57a334 · f57a334
1 parent c490974
commit f57a334
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Showing 2 changed files with 29 additions and 27 deletions.
diff --git a/clippy_utils/src/consts.rs b/clippy_utils/src/consts.rs
@@ -374,7 +374,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
             },
             ExprKind::Index(arr, index) => self.index(arr, index),
             ExprKind::AddrOf(_, _, inner) => self.expr(inner).map(|r| Constant::Ref(Box::new(r))),
-            // TODO: add other expressions.
+            ExprKind::Field(local_expr, _) => self.expr(local_expr),
             _ => None,
         }
     }
@@ -426,17 +426,14 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
             Res::Def(DefKind::Const | DefKind::AssocConst, def_id) => {
                 // Check if this constant is based on `cfg!(..)`,
                 // which is NOT constant for our purposes.
-                if let Some(node) = self.lcx.tcx.hir().get_if_local(def_id) &&
-                let Node::Item(&Item {
-                    kind: ItemKind::Const(_, body_id),
-                    ..
-                }) = node &&
-                let Node::Expr(&Expr {
-                    kind: ExprKind::Lit(_),
-                    span,
-                    ..
-                }) = self.lcx.tcx.hir().get(body_id.hir_id) &&
-                is_direct_expn_of(span, "cfg").is_some() {
+                if let Some(node) = self.lcx.tcx.hir().get_if_local(def_id)
+                    && let Node::Item(Item { kind: ItemKind::Const(_, body_id), .. }) = node
+                    && let Node::Expr(Expr { kind: ExprKind::Lit(_), span, .. }) = self.lcx
+                        .tcx
+                        .hir()
+                        .get(body_id.hir_id)
+                    && is_direct_expn_of(*span, "cfg").is_some()
+                {
                     return None;
                 }
 
@@ -446,7 +443,6 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 } else {
                     EarlyBinder(substs).subst(self.lcx.tcx, self.substs)
                 };
-
                 let result = self
                     .lcx
                     .tcx
@@ -606,20 +602,18 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
 pub fn miri_to_const<'tcx>(tcx: TyCtxt<'tcx>, result: mir::ConstantKind<'tcx>) -> Option<Constant> {
     use rustc_middle::mir::interpret::ConstValue;
     match result {
-        mir::ConstantKind::Val(ConstValue::Scalar(Scalar::Int(int)), _) => {
-            match result.ty().kind() {
-                ty::Bool => Some(Constant::Bool(int == ScalarInt::TRUE)),
-                ty::Uint(_) | ty::Int(_) => Some(Constant::Int(int.assert_bits(int.size()))),
-                ty::Float(FloatTy::F32) => Some(Constant::F32(f32::from_bits(
-                    int.try_into().expect("invalid f32 bit representation"),
-                ))),
-                ty::Float(FloatTy::F64) => Some(Constant::F64(f64::from_bits(
-                    int.try_into().expect("invalid f64 bit representation"),
-                ))),
-                ty::RawPtr(_) => Some(Constant::RawPtr(int.assert_bits(int.size()))),
-                // FIXME: implement other conversions.
-                _ => None,
-            }
+        mir::ConstantKind::Val(ConstValue::Scalar(Scalar::Int(int)), _) => match result.ty().kind() {
+            ty::Adt(_, _) => Some(Constant::Int(int.assert_bits(int.size()))),
+            ty::Bool => Some(Constant::Bool(int == ScalarInt::TRUE)),
+            ty::Uint(_) | ty::Int(_) => Some(Constant::Int(int.assert_bits(int.size()))),
+            ty::Float(FloatTy::F32) => Some(Constant::F32(f32::from_bits(
+                int.try_into().expect("invalid f32 bit representation"),
+            ))),
+            ty::Float(FloatTy::F64) => Some(Constant::F64(f64::from_bits(
+                int.try_into().expect("invalid f64 bit representation"),
+            ))),
+            ty::RawPtr(_) => Some(Constant::RawPtr(int.assert_bits(int.size()))),
+            _ => None,
         },
         mir::ConstantKind::Val(ConstValue::Slice { data, start, end }, _) => match result.ty().kind() {
             ty::Ref(_, tam, _) => match tam.kind() {

diff --git a/tests/ui/arithmetic_side_effects.rs b/tests/ui/arithmetic_side_effects.rs
@@ -466,4 +466,12 @@ pub fn issue_10767() {
     &3.5_f32 + &1.3_f32;
 }
 
+pub fn issue_10792() {
+    struct Foo {
+        bar: u32,
+    }
+    const FOO: Foo = Foo { bar: 2 };
+    let _ = 10 / FOO.bar;
+}
+
 fn main() {}