Re: c/10675: Compile time increases quadratically with struct size

[Zoltan Hidvegi <hzoli at hzoli dot 2y dot net>]

> Synopsis: Compile time increases quadratically with struct size
> 
> State-Changed-From-To: analyzed->closed
> State-Changed-By: rth
> State-Changed-When: Mon May 12 03:32:46 2003
> State-Changed-Why:
>     http://gcc.gnu.org/ml/gcc-patches/2003-05/msg00989.html
> 
> http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10675

I've applied the patch to the gcc-3.3 and manually fixed the
conflicts.  This does indeed fix the compile-time with gcc, but g++
still behaves quadratically.  Also for C++ you may want to run the
attached biggen3.sh, that will generate a struct as before, but it
adds a constructor that zero-initializes all members.  This also have
unusually large, although linear memory usage, e.g., the compile of a
struct with 25000 members with constructor initializers needs 55M
(based on the memory use showed by top on both AIX and Linux).  And
even C still seems to have slow lookups, as if the hash is only used
to detect duplicates, but for member lookup it still uses linear
search.  Run the attached biggen5.sh to test this, it will create a C
struct and a function that initializes the struct.  Because of all
this, I'd like to reopen this bug, or should I open a new bug?

Zoli

Attachment: biggen3.sh
Description: Text document

Attachment: biggen5.sh
Description: Text document