I think it's because w2c_rlbox_streqci is an "rlbox" sandboxed version
of the expat streqci function (https://rlbox.dev). It's transformed
somewhere and not necessarily even compiled by gcc. I don't know how
this web stuff, wasm, rlbox etc works, the toolchain is a total
mystery to me... I'm not even sure if new C source is generated or if
sandboxed functions are generated at compile time skipping C entirely.
But it does look as though there's a fair chance the source code
presented is what is eventually transformed into the asm code
presented. However the bug could equally be in the toolchain
somewhere...