firefox build broken

[Thomas Klausner <tk%giga.or.at@localhost>]

Hi!

It seems to me some recent change broke the firefox build.

I've built all packages from scratch on 9.99.59/amd64 from 20200426.

Firefox consistently fails with

stack backtrace:
   0:         0x490088e2 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hfc6622696269221b
   1:         0x490244ad - core::fmt::write::hd3eed79e7afa73cf
   2:         0x49007aa5 - std::io::Write::write_fmt::h60ea7d9604ed82bb
   3:         0x48ffae90 - std::panicking::default_hook::{{closure}}::h2c07f5fe2b4f82c2
   4:         0x48ffab82 - std::panicking::default_hook::h6dd6fafda250b80f
   5:         0x48ffb4ed - std::panicking::rust_panic_with_hook::hd4a4901bf3898ce4
   6:         0x48ffb0d0 - rust_begin_unwind
   7:         0x48ffb04b - std::panicking::begin_panic_fmt::h08093aab619d21cf
   8:         0x48e50244 - build_script_build::build_gecko::generate_structs::h05aae5803967982b
   9:         0x48e51dc6 - build_script_build::main::hdd2fcab7190374c2
  10:         0x48e38a53 - std::rt::lang_start::{{closure}}::h1cbbafc9225f7a3a
  11:         0x48ffafb3 - std::panicking::try::do_call::hf264ae5e639af05c
  12:         0x4900ec37 - __rust_maybe_catch_panic
  13:         0x48ffe8eb - std::rt::lang_start_internal::h63883908f6b782bf
  14:         0x48e52792 - main
  15:         0x48e35cfb - ___start

gmake[3]: *** [/scratch/www/firefox/work/firefox-75.0/config/makefiles/rust.mk:287: force-cargo-library-build] Error 101

Anyone else seen this?

firefox built fine for me on 20200423 with 9.99.57 from 20200422.
 Thomas