https://build.opensuse.org/projects/openSUSE:Factory/packages/chromium/files/chromium-140-keep-__rust_no_alloc_shim_is_unstable.patch
This is required to build with Rust <1.89.0, see https://github.com/rust-lang/rust/pull/141061
--- chromium-140.0.7339.5/build/rust/allocator/lib.rs
+++ chromium-140.0.7339.5/build/rust/allocator/lib.rs
@@ -90,6 +90,12 @@
     #[linkage = "weak"]
     fn __rust_no_alloc_shim_is_unstable_v2() {}
 
+    // TODO(crbug.com/422538133) Remove after rolling past
+    // https://github.com/rust-lang/rust/pull/141061
+    #[no_mangle]
+    #[linkage = "weak"]
+    static __rust_no_alloc_shim_is_unstable: u8 = 0;
+
     // Mangle the symbol name as rustc expects.
     #[rustc_std_internal_symbol]
     #[allow(non_upper_case_globals)]