Fix stack overflow by removing `Deref` and `DerefMut` impls

Marshall Bowers created 2 years ago

Change summary

Cargo.lock                          | 25 +++++++++++++++++++++++++
crates/gpui3/src/app.rs             | 19 ++++---------------
crates/storybook2/Cargo.toml        |  2 ++
crates/storybook2/src/storybook2.rs |  2 ++
4 files changed, 33 insertions(+), 15 deletions(-)

Detailed changes

Cargo.lock

@@ -758,6 +758,17 @@ dependencies = [
  "rustc-demangle",
 ]
 
+[[package]]
+name = "backtrace-on-stack-overflow"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fd2d70527f3737a1ad17355e260706c1badebabd1fa06a7a053407380df841b"
+dependencies = [
+ "backtrace",
+ "libc",
+ "nix 0.23.2",
+]
+
 [[package]]
 name = "bae"
 version = "0.1.7"
@@ -4692,6 +4703,19 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "nix"
+version = "0.23.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f3790c00a0150112de0f4cd161e3d7fc4b2d8a5542ffc35f099a2562aecb35c"
+dependencies = [
+ "bitflags 1.3.2",
+ "cc",
+ "cfg-if 1.0.0",
+ "libc",
+ "memoffset 0.6.5",
+]
+
 [[package]]
 name = "nix"
 version = "0.24.3"
@@ -7521,6 +7545,7 @@ name = "storybook2"
 version = "0.1.0"
 dependencies = [
  "anyhow",
+ "backtrace-on-stack-overflow",
  "gpui3",
  "log",
  "rust-embed",

crates/gpui3/src/app.rs

@@ -97,20 +97,6 @@ pub struct AppContext<Thread = ()> {
     pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
 }
 
-impl Deref for AppContext<MainThread> {
-    type Target = AppContext<()>;
-
-    fn deref(&self) -> &Self::Target {
-        self
-    }
-}
-
-impl DerefMut for AppContext<MainThread> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        self
-    }
-}
-
 impl<Thread> AppContext<Thread> {
     // TODO: Better names for these?
     #[inline]
@@ -333,7 +319,10 @@ impl AppContext<MainThread> {
         let id = self.windows.insert(None);
         let handle = WindowHandle::new(id);
         let mut window = Window::new(handle.into(), options, self);
-        let root_view = build_root_view(&mut WindowContext::mutable(self, &mut window));
+        let root_view = build_root_view(&mut WindowContext::mutable(
+            self.downcast_mut(),
+            &mut window,
+        ));
         window.root_view.replace(root_view.into_any());
         self.windows.get_mut(id).unwrap().replace(window);
         handle

crates/storybook2/Cargo.toml

@@ -10,6 +10,8 @@ path = "src/storybook2.rs"
 
 [dependencies]
 anyhow.workspace = true
+# TODO: Remove after diagnosing stack overflow.
+backtrace-on-stack-overflow = "0.3.0"
 gpui3 = { path = "../gpui3" }
 log.workspace = true
 rust-embed.workspace = true

crates/storybook2/src/storybook2.rs

@@ -14,6 +14,8 @@ mod workspace;
 // }
 
 fn main() {
+    unsafe { backtrace_on_stack_overflow::enable() };
+
     SimpleLogger::init(LevelFilter::Info, Default::default()).expect("could not initialize logger");
 
     gpui3::App::production().run(|cx| {