mismatched types - enif_make_long(env, i) ^ expected i32, found i64

[delta1]

Hey guys! In my excitement at the lovely improvements in #254 I'm trying to build against the current master branch (revision 5da9019)

I'm getting a weird error in cargo build, error: Could not compile 'rustler_sys'.

There are 4 errors about mismatched types in rustler_sys nif_api.snippet

Do you have any suggestions how I could fix this please?

error[E0308]: mismatched types
   --> C:\path\to\my_app\native\mynif\target\debug\build\rustler_sys-7ebc48992530b824\out/nif_api.snippet:907:27
    |
907 |     { enif_make_long(env, i) }
    |                           ^ expected i32, found i64
help: you can convert an `i64` to `i32` and panic if the converted value wouldn't fit
    |
907 |     { enif_make_long(env, i.try_into().unwrap()) }
    |                           ^^^^^^^^^^^^^^^^^^^^^

error[E0308]: mismatched types
   --> C:\path\to\my_app\native\mynif\target\debug\build\rustler_sys-7ebc48992530b824\out/nif_api.snippet:912:28
    |
912 |     { enif_make_ulong(env, i) }
    |                            ^ expected u32, found u64
help: you can convert an `u64` to `u32` and panic if the converted value wouldn't fit
    |
912 |     { enif_make_ulong(env, i.try_into().unwrap()) }
    |                            ^^^^^^^^^^^^^^^^^^^^^

error[E0308]: mismatched types
   --> C:\path\to\my_app\native\mynif\target\debug\build\rustler_sys-7ebc48992530b824\out/nif_api.snippet:917:32
    |
917 |     { enif_get_long(env, term, ip) }
    |                                ^^ expected i32, found i64
    |
    = note: expected type `*mut i32`
               found type `*mut i64`

error[E0308]: mismatched types
   --> C:\path\to\my_app\native\mynif\target\debug\build\rustler_sys-7ebc48992530b824\out/nif_api.snippet:922:33
    |
922 |     { enif_get_ulong(env, term, ip) }
    |                                 ^^ expected u32, found u64
    |
    = note: expected type `*mut u32`
               found type `*mut u64`

error: aborting due to 4 previous errors

I'm on windows but hopefully that's not an issue - rustler 0.21 works perfectly

Thank you for your time and this cool project!

[delta1]

cc @scrogson @filmor @scohen

[filmor]

Oh man, I don't know how often I've been bitten by this now. Windows uses 32bit longs even on 64bit archs, different from Unix. That means that the logic in https://github.com/rusterlium/rustler/blob/master/rustler_sys/build.rs#L31 that attempts to derive the size of long from the target pointer width is wrong.

I'll create a PR for this.

[delta1]

Today I learned! Thank you so much for your help, I can confirm that fixed the issue. Appreciated!