From bfa7d44823717c30bc21abc1ca3675d0b78c80a2 Mon Sep 17 00:00:00 2001
From: DrMeepster <19316085+DrMeepster@users.noreply.github.com>
Date: Sun, 27 Feb 2022 00:48:17 -0800
Subject: fix box icing when it has aggregate abi

---
 compiler/rustc_codegen_ssa/src/mir/place.rs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

(limited to 'compiler/rustc_codegen_ssa')

diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs
index 6976999c0e4..aee385ab050 100644
--- a/compiler/rustc_codegen_ssa/src/mir/place.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/place.rs
@@ -453,7 +453,18 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         };
         for elem in place_ref.projection[base..].iter() {
             cg_base = match elem.clone() {
-                mir::ProjectionElem::Deref => bx.load_operand(cg_base).deref(bx.cx()),
+                mir::ProjectionElem::Deref => {
+                    // custom allocators can change box's abi, making it unable to be derefed directly
+                    if cg_base.layout.ty.is_box()
+                        && matches!(cg_base.layout.abi, Abi::Aggregate { .. })
+                    {
+                        let ptr = cg_base.project_field(bx, 0).project_field(bx, 0);
+
+                        bx.load_operand(ptr).deref(bx.cx())
+                    } else {
+                        bx.load_operand(cg_base).deref(bx.cx())
+                    }
+                }
                 mir::ProjectionElem::Field(ref field, _) => {
                     cg_base.project_field(bx, field.index())
                 }
-- 
cgit 1.4.1-3-g733a5


From d316aba04c4644093ba07d1ec8d334b599b8eb01 Mon Sep 17 00:00:00 2001
From: DrMeepster <19316085+DrMeepster@users.noreply.github.com>
Date: Sun, 27 Feb 2022 20:25:16 -0800
Subject: expadn abi check + condese & fix tests

---
 compiler/rustc_codegen_ssa/src/mir/place.rs |  2 +-
 src/test/ui/box/issue-78459-ice.rs          |  6 ------
 src/test/ui/box/issue-81270-ice.rs          | 22 ----------------------
 src/test/ui/box/large-allocator-ice.rs      | 23 +++++++++++++++++++++++
 4 files changed, 24 insertions(+), 29 deletions(-)
 delete mode 100644 src/test/ui/box/issue-78459-ice.rs
 delete mode 100644 src/test/ui/box/issue-81270-ice.rs
 create mode 100644 src/test/ui/box/large-allocator-ice.rs

(limited to 'compiler/rustc_codegen_ssa')

diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs
index aee385ab050..809d6447908 100644
--- a/compiler/rustc_codegen_ssa/src/mir/place.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/place.rs
@@ -456,7 +456,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 mir::ProjectionElem::Deref => {
                     // custom allocators can change box's abi, making it unable to be derefed directly
                     if cg_base.layout.ty.is_box()
-                        && matches!(cg_base.layout.abi, Abi::Aggregate { .. })
+                        && matches!(cg_base.layout.abi, Abi::Aggregate { .. } | Abi::Uninhabited)
                     {
                         let ptr = cg_base.project_field(bx, 0).project_field(bx, 0);
 
diff --git a/src/test/ui/box/issue-78459-ice.rs b/src/test/ui/box/issue-78459-ice.rs
deleted file mode 100644
index 89f75fea15b..00000000000
--- a/src/test/ui/box/issue-78459-ice.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// check-pass
-#![feature(allocator_api)]
-
-fn main() {
-    Box::new_in((), &std::alloc::Global);
-}
diff --git a/src/test/ui/box/issue-81270-ice.rs b/src/test/ui/box/issue-81270-ice.rs
deleted file mode 100644
index fb42aed7aae..00000000000
--- a/src/test/ui/box/issue-81270-ice.rs
+++ /dev/null
@@ -1,22 +0,0 @@
-// check-pass
-#![feature(allocator_api)]
-
-use std::alloc::Allocator;
-
-struct BigAllocator([usize; 2]);
-
-unsafe impl Allocator for BigAllocator {
-    fn allocate(
-        &self,
-        _: std::alloc::Layout,
-    ) -> Result<std::ptr::NonNull<[u8]>, std::alloc::AllocError> {
-        todo!()
-    }
-    unsafe fn deallocate(&self, _: std::ptr::NonNull<u8>, _: std::alloc::Layout) {
-        todo!()
-    }
-}
-
-fn main() {
-    Box::new_in((), BigAllocator([0; 2]));
-}
diff --git a/src/test/ui/box/large-allocator-ice.rs b/src/test/ui/box/large-allocator-ice.rs
new file mode 100644
index 00000000000..3ef1171ff50
--- /dev/null
+++ b/src/test/ui/box/large-allocator-ice.rs
@@ -0,0 +1,23 @@
+// build-pass
+#![feature(allocator_api)]
+
+use std::alloc::Allocator;
+
+struct BigAllocator([usize; 2]);
+
+unsafe impl Allocator for BigAllocator {
+    fn allocate(
+        &self,
+        _: std::alloc::Layout,
+    ) -> Result<std::ptr::NonNull<[u8]>, std::alloc::AllocError> {
+        todo!()
+    }
+    unsafe fn deallocate(&self, _: std::ptr::NonNull<u8>, _: std::alloc::Layout) {
+        todo!()
+    }
+}
+
+fn main() {
+    Box::new_in((), &std::alloc::Global);
+    Box::new_in((), BigAllocator([0; 2]));
+}
-- 
cgit 1.4.1-3-g733a5