building error at lua.unwrap().include_paths[0]

[ildar]

having (ALTLinux) installation with

$ pkg-config --libs --cflags "lua" "lua >= 5.3" "lua < 5.4"
-llua -lm -ldl

building fails:

$ cd /tmp/remote-builds/mlua/ ; strace -fto /tmp/1.stra cargo b --features lua53
   Compiling mlua v0.7.0 (/tmp/remote-builds/mlua)
   Compiling serde v1.0.132
error: failed to run custom build command for `mlua v0.7.0 (/tmp/remote-builds/mlua)`

Caused by:
  process didn't exit successfully: `/tmp/remote-builds/mlua/target/debug/build/mlua-69c0ca88b62928dc/build-script-main` (exit status: 101)
  --- stdout
  cargo:rerun-if-env-changed=LUA_INC
...
  --- stderr
  thread 'main' panicked at 'index out of bounds: the len is 0 but the index is 0', build/find_normal.rs:75:9

Plz add the corresponding check. Thank you.

[khvzak]

Thanks, I updated error messages in 888b2bb

[ildar]

This is wrong. The problem isn't in a message. The problem is that pkg-config is not obliged to show any `-I` paths in case the headers are available at standard paths. I just tested and see the same error, just more verbose:

…

thread 'main' panicked at 'cannot find Lua 5.3 include paths using `pkg-config`', build/find_normal.rs:76:14

[khvzak]

The problem is that pkg-config is not obliged to show any -I paths in case the headers are available at standard paths.

Right, I see. It's quite weird case, means that altlinux does not support multiple Lua versions installed in the system?
I'll try to make include paths optional then.

[ildar]

On Tue, Dec 28, 2021 at 5:21 PM Alex Orlenko wrote: Right, I see. It's quite weird case, means that altlinux does not support multiple Lua versions installed in the system?

True.

[khvzak]

@ildar could you check again?

[ildar]

very good, worked fine. thank you.