[PATCH] bfd: stop over-allocating aux entries for COFF section symbols

[Oleg Tolmatcev]

coff_new_section_hook allocated ten combined_entry_type slots for every
section symbol, behind a comment conceding that the ten was a guess and
should not be a constant.  Nothing in BFD sets n_numaux above 1 on a
section symbol, and nothing indexes the array past native[1], so eight
of the ten were never touched on any target.

This runs once per input section, so it significantly reduces peak
memory usage.

bfd/
	* coffcode.h (coff_new_section_hook): Allocate one syment plus
	one aux entry rather than ten.

Signed-off-by: Oleg Tolmatcev <oleg.tolmatcev@gmail.com>
---
 bfd/coffcode.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

In one of my tests this reduces peak memory usage by 23%: 1497 MB out of 6532 MB.

diff --git a/bfd/coffcode.h b/bfd/coffcode.h
index 964d2c3e173..6875f856c08 100644
--- a/bfd/coffcode.h
+++ b/bfd/coffcode.h
@@ -1831,9 +1831,9 @@ coff_new_section_hook (bfd * abfd, asection * section)
   /* Allocate aux records for section symbols, to store size and
      related info.
 
-     @@ The 10 is a guess at a plausible maximum number of aux entries
-     (but shouldn't be a constant).  */
-  amt = sizeof (combined_entry_type) * 10;
+     One syment plus one aux: nothing sets n_numaux above 1 on a
+     section symbol, or indexes this array past native[1].  */
+  amt = sizeof (combined_entry_type) * 2;
   native = (combined_entry_type *) bfd_zalloc (abfd, amt);
   if (native == NULL)
     return false;
-- 
2.55.0.windows.3