* amd64fbsd-nat.c (amd64fbsd_supply_pcb): Add comment.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 8f324fb..0c83a78 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2009-10-19  Joel Brobecker  <brobecker@adacore.com>
+
+       * amd64fbsd-nat.c (amd64fbsd_supply_pcb): Add comment.
+
 2009-10-19  Pedro Alves  <pedro@codesourcery.com>
            Stan Shebs  <stan@codesourcery.com>
 

diff --git a/gdb/amd64fbsd-nat.c b/gdb/amd64fbsd-nat.c
index 5a93ec3..eb15489 100644 (file)
--- a/gdb/amd64fbsd-nat.c
+++ b/gdb/amd64fbsd-nat.c
@@ -125,6 +125,11 @@ amd64fbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
   regcache_raw_supply (regcache, 14, &pcb->pcb_r14);
   regcache_raw_supply (regcache, 15, &pcb->pcb_r15);
 #if (__FreeBSD_version <  800075)
+  /* struct pcb provides the pcb_ds/pcb_es/pcb_fs/pcb_gs fields only
+     up until __FreeBSD_version 800074: The removal of these fields
+     occurred on 2009-04-01 while the __FreeBSD_version number was
+     bumped to 800075 on 2009-04-06.  So 800075 is the closest version
+     number where we should not try to access these fields.  */
   regcache_raw_supply (regcache, AMD64_DS_REGNUM, &pcb->pcb_ds);
   regcache_raw_supply (regcache, AMD64_ES_REGNUM, &pcb->pcb_es);
   regcache_raw_supply (regcache, AMD64_FS_REGNUM, &pcb->pcb_fs);