Re-enable rustc overflow checks

CHANGELOG.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 - Synchronized with `polkadot-sdk/c40b36c3a7c208f9a6837b80812473af3d9ba7f7` ‒ [2102](https://github.com/use-ink/cargo-contract/pull/2102)
+- Re-enable `rustc` overflow checks - [#2116](https://github.com/use-ink/cargo-contract/pull/2116)
 
 ### Removed
 - Removed chain extension functionality ‒ [2120](https://github.com/use-ink/cargo-contract/pull/2120)

crates/build/src/lib.rs

@@ -357,7 +357,10 @@ fn exec_cargo_for_onchain_target(
         if build_mode == &BuildMode::Debug {
             features.push("ink/ink-debug".to_string());
         } else {
-            args.push("-Zbuild-std-features=panic_immediate_abort".to_owned());
+            args.push(
+                "-Zbuild-std-features=panic_immediate_abort,compiler-builtins-mem"
+                    .to_owned(),
+            );
         }
         features.append_to_args(&mut args);
         let mut env = Vec::new();

crates/build/src/workspace/manifest.rs

@@ -134,19 +134,11 @@ impl Manifest {
     pub fn new(manifest_path: ManifestPath) -> Result<Manifest> {
         let toml = fs::read_to_string(&manifest_path).context("Loading Cargo.toml")?;
         let toml: value::Table = toml::from_str(&toml)?;
-        let mut manifest = Manifest {
+        let manifest = Manifest {
             path: manifest_path,
             toml,
             metadata_package: false,
         };
-        let profile = manifest.profile_release_table_mut()?;
-        if profile
-            .get("overflow-checks")
-            .and_then(|val| val.as_bool())
-            .unwrap_or(false)
-        {
-            anyhow::bail!("Overflow checks must be disabled. Cargo contract makes sure that no unchecked arithmetic is used.")
-        }
         Ok(manifest)
     }
 

crates/build/src/workspace/profile.rs

@@ -27,6 +27,7 @@ pub struct Profile {
     // `None` means use rustc default.
     pub codegen_units: Option<u32>,
     pub panic: Option<PanicStrategy>,
+    pub overflow_checks: Option<bool>,
 }
 
 impl Profile {
@@ -37,6 +38,7 @@ impl Profile {
             lto: Some(Lto::Fat),
             codegen_units: Some(1),
             panic: Some(PanicStrategy::Abort),
+            overflow_checks: Some(true),
         }
     }
 
@@ -73,6 +75,7 @@ impl Profile {
             self.panic.map(PanicStrategy::to_toml_value),
             profile,
         );
+        set_value_if_vacant("overflow-checks", self.overflow_checks, profile);
     }
 }
 
@@ -159,6 +162,7 @@ mod tests {
         expected.insert("lto".into(), value::Value::String("fat".into()));
         expected.insert("codegen-units".into(), value::Value::Integer(1));
         expected.insert("panic".into(), value::Value::String("abort".into()));
+        expected.insert("overflow-checks".into(), value::Value::Boolean(true));
 
         let mut manifest_profile = toml::from_str(manifest_toml).unwrap();
 
@@ -176,12 +180,14 @@ mod tests {
             lto = false
             opt-level = 3
             codegen-units = 256
+            overflow-checks = false
         "#;
         let mut expected = value::Table::new();
         expected.insert("opt-level".into(), value::Value::Integer(3));
         expected.insert("lto".into(), value::Value::Boolean(false));
         expected.insert("codegen-units".into(), value::Value::Integer(256));
         expected.insert("panic".into(), value::Value::String("unwind".into()));
+        expected.insert("overflow-checks".into(), value::Value::Boolean(false));
 
         let mut manifest_profile = toml::from_str(manifest_toml).unwrap();