Bug 1583907 - Add MOZ_NEVER_INLINE to LifoAlloc::mark to work around Clang 9 miscompilation on Android. r=nbp

Differential Revision: https://phabricator.services.mozilla.com/D47435

--HG--
extra : moz-landing-system : lando

Author: jandem

js/src/ds/LifoAlloc.h

@@ -764,7 +764,11 @@ class LifoAlloc {
     detail::BumpChunk::Mark chunk;
     detail::BumpChunk::Mark oversize;
   };
-  Mark mark();
+
+  // Note: MOZ_NEVER_INLINE is a work around for a Clang 9 (PGO) miscompilation.
+  // See bug 1583907.
+  MOZ_NEVER_INLINE Mark mark();
+
   void release(Mark mark);
 
  private: