diff -up firefox-60.0/mfbt/LinuxSignal.h.mozilla-1238661 firefox-60.0/mfbt/LinuxSignal.h

--- firefox-60.0/mfbt/LinuxSignal.h.mozilla-1238661	2018-04-27 08:55:38.848241768 +0200

+++ firefox-60.0/mfbt/LinuxSignal.h	2018-04-27 09:06:47.946769859 +0200

@@ -25,10 +25,13 @@ SignalTrampoline(int aSignal, siginfo_t*

     "nop; nop; nop; nop"

     : : : "memory");

+  // Because the assembler may generate additional insturctions below, we

+  // need to ensure NOPs are inserted first by separating them out above.

+

   asm volatile (

-    "b %0"

+    "bx %0"

     :

-    : "X"(H)

+    : "r"(H), "l"(aSignal), "l"(aInfo), "l"(aContext)

     : "memory");

 }