[petsc-dev] speaking of being drunk while writing code

[Barry Smith]

   It takes some serious beer goggles to mix up SNES and DM (same problem with 
KSP and TS)



  /* This is NOT reference counted. The SNES that originally created this 
context is cached here to implement copy-on-write.
   * Fields in the SNESDM should only be written if the SNES matches 
originalsnes.
   */
  DM originaldm;