diff -r 97a6da6d7e29 -r 8a4f5aea2475 mozilla-reduce-rust-debuginfo.patch
--- a/mozilla-reduce-rust-debuginfo.patch	Sun Oct 20 14:25:55 2019 +0200
+++ b/mozilla-reduce-rust-debuginfo.patch	Fri Oct 25 11:19:31 2019 +0200
@@ -3,27 +3,42 @@
 # Date 1560754926 -7200
 #      Mon Jun 17 09:02:06 2019 +0200
 # Node ID 428161c3b9599083e1b8710eda1760f1f707ab11
-# Parent  6cd963b6c82ea6629aaf4050851789b78f310338
+# Parent  fa1cf8b9cb4efdf89fe19e543fb54272b726a353
 #Description: reduce the rust debuginfo level on selected architectures where
 # compiling with debuginfo=2 causes the OOM killer to interrupt the build on
 # launchpad builders. Initially this was only on 32 bit architectures, but with
 # firefox 63 it started happening frequently on arm64 and ppc64el too.
 
-diff -r 6cd963b6c82e -r 428161c3b959 build/moz.configure/toolchain.configure
---- a/build/moz.configure/toolchain.configure	Tue May 21 17:26:58 2019 +0200
-+++ b/build/moz.configure/toolchain.configure	Mon Jun 17 09:02:06 2019 +0200
-@@ -1865,8 +1865,8 @@
+diff --git a/build/moz.configure/toolchain.configure b/build/moz.configure/toolchain.configure
+--- a/build/moz.configure/toolchain.configure
++++ b/build/moz.configure/toolchain.configure
+@@ -1861,18 +1861,18 @@ imply_option('RUSTC_OPT_LEVEL', '2', whe
+ @depends('RUSTC_OPT_LEVEL', moz_optimize)
+ def rustc_opt_level(opt_level_option, moz_optimize):
+     if opt_level_option:
+         return opt_level_option[0]
+     else:
          return '1' if moz_optimize.optimize else '0'
  
  
--@depends(rustc_opt_level, debug_rust, '--enable-debug-symbols')
--def rust_compile_flags(opt_level, debug_rust, debug_symbols):
-+@depends(rustc_opt_level, debug_rust, '--enable-debug-symbols', host)
-+def rust_compile_flags(opt_level, debug_rust, debug_symbols, host):
+-@depends(rustc_opt_level, debug_rust, '--enable-debug-symbols', '--enable-frame-pointers')
+-def rust_compile_flags(opt_level, debug_rust, debug_symbols, frame_pointers):
++@depends(rustc_opt_level, debug_rust, '--enable-debug-symbols', '--enable-frame-pointers', host)
++def rust_compile_flags(opt_level, debug_rust, debug_symbols, frame_pointers, host):
      # Cargo currently supports only two interesting profiles for building:
      # development and release. Those map (roughly) to --enable-debug and
      # --disable-debug in Gecko, respectively.
-@@ -1889,6 +1889,8 @@
+     #
+     # But we'd also like to support an additional axis of control for
+     # optimization level. Since Cargo only supports 2 profiles, we're in
+     # a bit of a bind.
+     #
+@@ -1885,16 +1885,18 @@ def rust_compile_flags(opt_level, debug_
+ 
+     # opt-level=0 implies -C debug-assertions, which may not be desired
+     # unless Rust debugging is enabled.
+     if opt_level == '0' and not debug_rust:
+         debug_assertions = False
  
      if debug_symbols:
          debug_info = '2'
@@ -32,3 +47,8 @@
  
      opts = []
  
+     if opt_level is not None:
+         opts.append('opt-level=%s' % opt_level)
+     if debug_assertions is not None:
+         opts.append('debug-assertions=%s' %
+                     ('yes' if debug_assertions else 'no'))