scratch/igc updated (8d4e37dfedd -> dd16f5a1864)

[Gerd Moellmann]

gerd pushed a change to branch scratch/igc.

      from  8d4e37dfedd Alloc hash table user tests as roots
       new  b6de3b87acb Add a igc_xpalloc_exact function
       new  dd16f5a1864 Allocate prstack as exact root


Summary of changes:
 src/igc.c   | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++-------
 src/igc.h   | 18 ++++++++++++++++--
 src/print.c | 40 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 107 insertions(+), 9 deletions(-)