Hi,

jemalloc-sys currently fails to build from source on Debian (see buildd logs). The cause is that configure didn't recognize riscv64gc.

Testing reveals that, when using its autogen.sh, jemalloc successfully builds itself. However, with the current setting of this crate's build.rs, a bundled, pre-generated configure is used, which fails.

Running autogen.sh seems trivial, and it's available since jemalloc is submoduled. Is there anything that prevents its use?