cargo build failure on openindiana

[3eka]

Hi all,
i was able to build this (fantastic) tool back on Aug 26th, 2021, with

:; rustc --version
rustc 1.44.1

:; difftastic --version
Difftastic 0.8.0

:; file difftastic
difftastic: ELF 64-bit LSB executable, x86-64, version 1 (Solaris), dynamically linked, interpreter /usr/lib/amd64/ld.so.1, not stripped

with this sequence:

:; git clone https://github.com/Wilfred/difftastic && cd difftastic
:; cargo build --release --jobs 1

now, it fails with error:

   Compiling tree-sitter v0.20.0                                                                                                                                                                             
   Compiling colored v2.0.0                                                                           
   Compiling clap v2.33.3                                                                                                                                                                                    
error[E0658]: `if` is not allowed in a `const fn`                                                                                                                                                            
  --> /export/home/predrag_zecevic/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-2.33.3/src/app/settings.rs:7:1
   |                                                                                                  
7  | / bitflags! {                                                                                    
8  | |     struct Flags: u64 {
9  | |         const SC_NEGATE_REQS       = 1;
10 | |         const SC_REQUIRED          = 1 << 1;
...  |
51 | |     }
52 | | }
   | |_^
   |
   = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information
   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0658]: `if` is not allowed in a `const fn`
  --> /export/home/predrag_zecevic/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-2.33.3/src/args/settings.rs:6:1
   |
6  | / bitflags! {
7  | |     struct Flags: u32 {
8  | |         const REQUIRED         = 1;
9  | |         const MULTIPLE         = 1 << 1;
...  |
28 | |     }
29 | | }
   | |_^
   |
   = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information
   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.
error: could not compile `clap`.

To learn more, run the command again with --verbose.

Any idea what I am doing wrong?
Regards.

[Wilfred]

That looks like clap (the argument parser library) now requires a newer version of rustc than what you have installed.

I should really pin a specific rust version in CI, so it's clear what the build requirements are.

[Wilfred]

OK, looks like Rust 1.46 is required, due to clap depending on bitflags.

[3eka]

Thanks @Wilfred - all clear now