fix: patch libmimalloc-sys to use upstream fix for cross-compilation

Use git version of libmimalloc-sys from master branch which includes
the fix for -Wdate-time cross-compilation issue (PR #139).

The upstream fix adds -Wno-error=date-time flag to the build script
for non-Windows targets, which resolves the compilation error when
cross-compiling to ARM architectures (aarch64, armv7).

This allows us to:
- Use mimalloc on all architectures (not just x86_64)
- Remove conditional compilation workarounds
- Get the performance benefits of mimalloc everywhere

Reference: purpleprotocol/mimalloc_rust#139

Author: AndPuQing

Cargo.lock

@@ -89,14 +89,18 @@ socket2 = "0.6"
 libc = "0.2"
 clap-verbosity-flag = { version = "3.0.4", default-features = false, features = ["tracing"] }
 chrono = { version = "0.4.42", features = ["clock"] }
-mimalloc = { version = "0.1", features = ["v3"], optional = true }
+mimalloc = { version = "0.1", features = ["v3"] }
 compact_str = { version = "0.9", features = ["serde"] }
 smallvec = { version = "1.13", features = ["serde"] }
 
 [features]
-default = ["mimalloc"]
+default = []
 metrics = ["prometheus", "lazy_static"]
-mimalloc = ["dep:mimalloc"]
+
+[patch.crates-io]
+# Use git version with fix for -Wdate-time cross-compilation issue
+# https://github.com/purpleprotocol/mimalloc_rust/pull/139
+libmimalloc-sys = { git = "https://github.com/purpleprotocol/mimalloc_rust", branch = "master" }
 
 [build-dependencies]
 anyhow = "1.0.95"

Cargo.toml

@@ -1,8 +1,5 @@
-// Use mimalloc only on x86_64 to avoid cross-compilation issues
-#[cfg(all(feature = "mimalloc", target_arch = "x86_64"))]
 use mimalloc::MiMalloc;
 
-#[cfg(all(feature = "mimalloc", target_arch = "x86_64"))]
 #[global_allocator]
 static GLOBAL: MiMalloc = MiMalloc;