musl: Change `time_t` definition on 32-bit targets according to "time64"

[JohnTitor]

time_t is defined as c_long on musl:

libc/src/unix/linux_like/linux/musl/mod.rs

Line 3 in b1268e4

pub type time_t = c_long;

and c_long is i32 on 32-bit targets:

libc/src/unix/linux_like/linux/musl/b32/mod.rs

Line 1 in b1268e4

pub type c_long = i32;

But the time_t definition has been changed to 64-bit by https://github.com/bminor/musl/commit/38143339646a4ccce8afe298c34467767c899f51, since musl 1.2.0.
We will change our type to i64 on 32-bit targets as well at some point but we should announce it before changing.
cc #1846

Implementation history:

• Basic support Start update to musl v1.2.3 #4443
• time_t changes musl: 64-bit time support #4463

[mahkoh]

Isn't this broken either way as soon as C libraries are involved or am I missing something?

As documented in time64.html, C code compiled against >=1.2 assumes time_t = i64 whereas code compiled against <1.2 assumes time_t = i32 on 32 bit systems. If you use a C library that uses time_t in its interface (e.g. openssl), the time_t used by rust code must have the same size as in the musl headers.

[abcfy2]

Any updates? I'm facing the same issue when building openssl:

   Compiling shadowsocks-rust v1.8.19 (/project)
error: linking with `arm-linux-musleabi-gcc` failed: exit code: 1
  |
  = note: "arm-linux-musleabi-gcc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-Wl,--eh-frame-hdr" "-nostartfiles" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib/self-contained/crt1.o" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib/self-contained/crti.o" "-L" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib" "-L" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib/self-contained" "/target/arm-unknown-linux-musleabi/release/deps/ssurl-b511399b1b3e9edd.ssurl.1o5mikv8-cgu.0.rcgu.o" "-o" "/target/arm-unknown-linux-musleabi/release/deps/ssurl-b511399b1b3e9edd" "-Wl,--gc-sections" "-static" "-no-pie" "-Wl,-zrelro" "-Wl,-znow" "-Wl,-O1" "-nodefaultlibs" "-L" "/target/arm-unknown-linux-musleabi/release/deps" "-L" "/target/release/deps" "-L" "/target/arm-unknown-linux-musleabi/release/build/libsodium-sys-af7e3974b41e2f39/out/installed/lib" "-L" "/target/arm-unknown-linux-musleabi/release/build/openssl-sys-ddefbd6d719725b9/out/openssl-build/install/lib" "-L" "/target/arm-unknown-linux-musleabi/release/build/ring-c1bb5f055649313e/out" "-L" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib" "-Wl,-Bstatic" "/tmp/rustc2sPxVB/libring-7676a44ad52e73ec.rlib" "/tmp/rustc2sPxVB/liblibsodium_sys-8f2b5176646fe1cb.rlib" "/tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib" "-Wl,--start-group" "/tmp/rustc2sPxVB/libunwind-bb2d2101beb6f64d.rlib" "/tmp/rustc2sPxVB/liblibc-ae22292566331366.rlib" "-Wl,--end-group" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib/libcompiler_builtins-1aed8fa9822aaf63.rlib" "-Wl,-Bdynamic" "/rust/lib/rustlib/arm-unknown-linux-musleabi/lib/self-contained/crtn.o"
  = note: /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(drbg_lib.o): in function `RAND_DRBG_instantiate':
          drbg_lib.c:(.text.RAND_DRBG_instantiate+0x180): undefined reference to `__time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(drbg_lib.o): in function `RAND_DRBG_reseed':
          drbg_lib.c:(.text.RAND_DRBG_reseed+0x154): undefined reference to `__time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(drbg_lib.o): in function `RAND_DRBG_generate':
          drbg_lib.c:(.text.RAND_DRBG_generate+0x164): undefined reference to `__time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(rand_unix.o): in function `check_random_device':
          rand_unix.c:(.text.check_random_device+0x28): undefined reference to `__fstat_time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(rand_unix.o): in function `wait_random_seeded':
          rand_unix.c:(.text.wait_random_seeded+0x184): undefined reference to `__select_time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(rand_unix.o): in function `rand_pool_acquire_entropy':
          rand_unix.c:(.text.rand_pool_acquire_entropy+0x134): undefined reference to `__fstat_time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(rand_unix.o): in function `rand_pool_add_nonce_data':
          rand_unix.c:(.text.rand_pool_add_nonce_data+0x44): undefined reference to `__clock_gettime64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: rand_unix.c:(.text.rand_pool_add_nonce_data+0x88): undefined reference to `__gettimeofday_time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: rand_unix.c:(.text.rand_pool_add_nonce_data+0xb0): undefined reference to `__time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(rand_unix.o): in function `rand_pool_add_additional_data':
          rand_unix.c:(.text.rand_pool_add_additional_data+0x74): undefined reference to `__clock_gettime64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: rand_unix.c:(.text.rand_pool_add_additional_data+0x9c): undefined reference to `__gettimeofday_time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: rand_unix.c:(.text.rand_pool_add_additional_data+0xc4): undefined reference to `__time64'
          /usr/local/bin/../lib/gcc/arm-linux-musleabi/9.2.0/../../../../arm-linux-musleabi/bin/ld: /tmp/rustc2sPxVB/libopenssl_sys-0f67a64037e617dd.rlib(conf_def.o): in function `def_load_bio':
          conf_def.c:(.text.def_load_bio+0x5dc): undefined reference to `__stat_time64'
          collect2: error: ld returned 1 exit status

[nagisa]

The added deprecation notice is now making the libstd build to fail, as it depends on said type.

This means that libstd is either stuck on 0.2.79 for indeterminate amount of time or we need to figure out a way to support either version of musl or give users ability to specify the version of musl they target?

[JohnTitor]

This means that libstd is either stuck on 0.2.79 for indeterminate amount of time or we need to figure out a way to support either version of musl or give users ability to specify the version of musl they target?

It's related to #1412 but we don't have any policy for supported platforms. Yes, both ways are better than just changing the type (also cc #547).