From e108da9dc263aa28fed4b5a51d5e08311be2355f Mon Sep 17 00:00:00 2001 From: James Kay Date: Wed, 11 Mar 2026 02:25:56 +0000 Subject: [PATCH 1/2] `std`: include `dlmalloc` for all non-wasi Wasm targets Currently, building std for a custom Wasm target with an OS other than `unknown` will fail, because `sys/alloc/mod.rs` will attempt to use `sys/alloc/wasm.rs`, the dlmalloc-based allocator used on `wasm32-unknown-unknown`. However, currently dlmalloc is only pulled in when `target_os = "unknown"`. Instead, we should make `Cargo.toml` and `alloc/mod.rs` match: either - disable `wasm.rs` in `alloc/mod.rs` where `not(target_os = "unknown")`, or - pull in `dlmalloc` for all Wasm targets with `target_family = "wasm32"` that aren't covered by the [upper branches of `alloc/mod.rs`](https://github.com/rust-lang/rust/blob/main/library/std/src/sys/alloc/mod.rs#L72-L100). This PR takes the latter approach, because it allows more code to compile without a custom allocator. --- library/std/Cargo.toml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml index 1b7a41d697367..740d37617547c 100644 --- a/library/std/Cargo.toml +++ b/library/std/Cargo.toml @@ -62,7 +62,7 @@ path = "../windows_link" rand = { version = "0.9.0", default-features = false, features = ["alloc"] } rand_xorshift = "0.4.0" -[target.'cfg(any(all(target_family = "wasm", target_os = "unknown"), target_os = "xous", target_os = "vexos", all(target_vendor = "fortanix", target_env = "sgx")))'.dependencies] +[target.'cfg(any(all(target_family = "wasm", not(target_os = "wasi")), target_os = "xous", target_os = "vexos", all(target_vendor = "fortanix", target_env = "sgx")))'.dependencies] dlmalloc = { version = "0.2.10", features = ['rustc-dep-of-std'] } [target.x86_64-fortanix-unknown-sgx.dependencies] From e2923eb86a18b2e288e88605a61c21fcc38f8c82 Mon Sep 17 00:00:00 2001 From: James Kay Date: Wed, 11 Mar 2026 16:49:12 +0000 Subject: [PATCH 2/2] `std`: don't depend on `dlmalloc` when `cfg(unix)` --- library/std/Cargo.toml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml index 740d37617547c..7a8ccdbc5043b 100644 --- a/library/std/Cargo.toml +++ b/library/std/Cargo.toml @@ -62,7 +62,7 @@ path = "../windows_link" rand = { version = "0.9.0", default-features = false, features = ["alloc"] } rand_xorshift = "0.4.0" -[target.'cfg(any(all(target_family = "wasm", not(target_os = "wasi")), target_os = "xous", target_os = "vexos", all(target_vendor = "fortanix", target_env = "sgx")))'.dependencies] +[target.'cfg(any(all(target_family = "wasm", not(any(unix, target_os = "wasi"))), target_os = "xous", target_os = "vexos", all(target_vendor = "fortanix", target_env = "sgx")))'.dependencies] dlmalloc = { version = "0.2.10", features = ['rustc-dep-of-std'] } [target.x86_64-fortanix-unknown-sgx.dependencies]