fix: support musl libc target for linux platform by loyalpartner · Pull Request #11 · bytedance/ipmb

loyalpartner · 2025-12-04T08:32:43Z

Use mem::zeroed() to initialize msghdr struct instead of struct literal
syntax, as musl libc has private padding fields (__pad1, __pad2) that
prevent direct construction. Also add type casts for msg_controllen and
cmsg_len to handle the type difference between musl (u32) and glibc
(usize).

target - Replace manual msghdr struct initialization with mem::zeroed() for safety - Fix type conversion for msg_controllen field from usize to libc type - Fix type conversion for cmsg_len field in control count calculation - Apply consistent unsafe zeroed initialization for both send and receive paths

loyalpartner · 2025-12-04T08:35:55Z

cargo build --target=x86_64-unknown-linux-musl -p ipmb
Compiling ipmb v0.8.4 (/home/lee/tmp/ipmb/ipmb)
error: cannot construct msghdr with struct literal syntax due to private fields
--> ipmb/src/platform/linux/encoded_message.rs:45:27
|
45 | let mut hdr = libc::msghdr {
| ^^^^^^^^^^^^
|
= note: ...and other private fields __pad1 and __pad2 that were not provided

error[E0308]: mismatched types
--> ipmb/src/platform/linux/encoded_message.rs:77:34
|
77 | hdr.msg_controllen = control_data.len();
| ------------------ ^^^^^^^^^^^^^^^^^^ expected u32, found usize
| |
| expected due to the type of this binding

error[E0308]: mismatched types
--> ipmb/src/platform/linux/encoded_message.rs:98:23
|
98 | - (control_data_ptr as usize - control_ptr as usize))
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected u32, found usize

error[E0277]: cannot subtract usize from u32
--> ipmb/src/platform/linux/encoded_message.rs:98:21
|
98 | - (control_data_ptr as usize - control_ptr as usize))
| ^ no implementation for u32 - usize
|
= help: the trait Sub<usize> is not implemented for u32
= help: the following other types implement trait Sub<Rhs>:
&u32 implements Sub<u32>
&u32 implements Sub
u32 implements Sub<&u32>
u32 implements Sub

error[E0308]: mismatched types
--> ipmb/src/platform/linux/encoded_message.rs:99:23
|
99 | / mem::size_of::();
| ^^^^^^^^^^^^^^^^^^^^^^^ expected u32, found usize

error[E0277]: cannot divide u32 by usize
--> ipmb/src/platform/linux/encoded_message.rs:99:21
|
99 | / mem::size_of::();
| ^ no implementation for u32 / usize
|
= help: the trait Div<usize> is not implemented for u32
= help: the following other types implement trait Div<Rhs>:
&u32 implements Div<u32>
&u32 implements Div
u32 implements Div<&u32>
u32 implements Div<NonZero<u32>>
u32 implements Div

error: cannot construct msghdr with struct literal syntax due to private fields
--> ipmb/src/platform/linux/encoded_message.rs:156:23
|
156 | let mut hdr = libc::msghdr {
| ^^^^^^^^^^^^
|
= note: ...and other private fields __pad1 and __pad2 that were not provided

error[E0308]: mismatched types
--> ipmb/src/platform/linux/encoded_message.rs:171:30
|
171 | hdr.msg_controllen = self.control_data.len();
| ------------------ ^^^^^^^^^^^^^^^^^^^^^^^ expected u32, found usize
| |
| expected due to the type of this binding

Some errors have detailed explanations: E0277, E0308.
For more information about an error, try rustc --explain E0277.
error: could not compile ipmb (lib) due to 8 previous errors
❯ cargo build --target=x86_64-unknown-linux-musl -p ipmb | wl-copy
Compiling ipmb v0.8.4 (/home/lee/tmp/ipmb/ipmb)
error: cannot construct msghdr with struct literal syntax due to private fields
--> ipmb/src/platform/linux/encoded_message.rs:45:27
|
45 | let mut hdr = libc::msghdr {
| ^^^^^^^^^^^^
|
= note: ...and other private fields __pad1 and __pad2 that were not provided