When building on Linux, I see:
rustc -C linker=cc --color=always --crate-type rlib --crate-name rs_math -g --emit dep-info=rs_math.d --emit link -L /usr/lib/x86_64-linux-gnu -o librs_math.rlib -l static=m ../rs_math.rs
error: failed to add native library /usr/lib/x86_64-linux-gnu/libm.a: file too small to be an archive
I think the "file too small to be an archive" message is coming from
libLLVM, and is a case of LLVM not handling this type of "script
archive". So, possibly this is just LLVM not handling a linking case.
The rust_args usage in meson.build is invalid, but required to
reproduce the issue in the test case. Perhaps meson should
automatically add the library include path via the dep_m meson object,
or maybe the meson.build can add the link path in a better way.
Changing '-l static=m' to '-l dylib=m' appears to fix this case. (See
comments in meson.build.)