Currently, the Rust module in 389-ds-base is built without default Fedora compiler flags for Rust code (i.e. "-Copt-level=3 -Cdebuginfo=2 -Ccodegen-units=1 -Clink-arg=-Wl,-z,relro -Clink-arg=-Wl,-z,now --cap-lints=warn") - essentially, the code is not fully optimized, and does not contain debuginfo or frame pointers.

RUSTFLAGS are the standard environment variable for setting compiler flags for rustc (similar to CFLAGS / CXXFLAGS / LDFLAGS), but they aren't set by default (and not yet included in %set_build_flags, but I've reported an RFE about this).

It appears that the 389-ds-base build system currently hard-codes these compiler flags: --release --verbose -- -C debuginfo=2

This results in Rust code compiled as part of 389-ds-base not being optimized at the same level as other Rust code in Fedora (i.e. `-Copt-level=3` is default in Fedora, but `--release` mode only implies `-Copt-level=2`), and it also doesn't include the other mandatory compiler flags, which result in better quality of generated code (and on rawhide, includes frame pointers on x86_64 and aarch64).